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WRAF213

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  1. Like
    WRAF213 got a reaction from WRPK468 in Why "More Power" Isn't The Answer   
    Absolutely, finding higher ground should be the first step towards improving a setup. Running more power only matters on fixed setups where the antenna is already as good as it can get, or on mobile operation where there is no 'finding a good spot'. Even then, there's not a huge difference between 15 and 40 watts.
     
    Here's my first piece of advice for new users (and I have a bunch, fair warning): use scan mode on a radio that will tell you the active CTCSS tone or DCS code if you're looking for repeaters to use. RTL-SDR is also a good tool, and makes the entire 462 MHz band visible with good sensitivity and excellent selectivity.
     
    Especially on fixed setups, grounding is important. Noise will get picked up along the coax and travel up to the antenna, where it enters the receiver. The effect is very apparent on SDRs, where the noise floor is directly visible. When grounding a setup, check for ground loops with a multimeter.
     
    Learn to recognize the busy-channel indicator on your radio. When the radio detects any activity on the channel, regardless of correct CTCSS/DCS, it'll turn on the busy-channel indicator. It'll help you to know if you have the correct CTCSS/DCS for a particular system. Some repeaters use multiple CTCSS/DCS, so this indicator can be useful on those repeaters to make sure you aren't interfering with a different conversation. On Baofeng's radios, this is the green LED on top of the radio. On Motorola's commercial radios, this is a blinking red or green LED near the antenna; on their FRS/GMRS radios, this is the red LED above the display.
     
    Some repeaters transmit CTCSS/DCS back to you, but only while someone is transmitting to it. If you're hitting the repeater but can't hear it come back to you once you finish transmitting, this could be a possible cause. Use the monitor feature on your radio or check the busy-channel indicator to check for the repeater's tail.
     
    Don't be afraid to try simplex. If you hear a callsign with variable signal strength, they're probably not going through a repeater. It's rare to find contacts that way, but that's largely because hardly anyone calls for contacts on simplex. 462.5625 (channel 1), transmit and receive CSQ; and 462.6750 (channel 20), transmit CTCSS 141.3 and receive CSQ are good places to try calling CQ.
     
    People who use MDC-1200 on their radios don't actually have to hear the data bursts, the radio can detect the burst and mute it. It gets annoying so most people with MDC-1200 radios have their radios like that.
     
    This forum sure does love their Kenwood TK-880s and Motorola M1225s. They're great radios, but terrible general-purpose radios. Virtually all commercial radios can only be programmed by computer software, so you have to know ahead of time what you're going to talk to. Speaking of commercial radios, used Motorola HT1000 radios are incredibly durable and inexpensive. They use the same programming
     
    Don't waste your money on the BTech GMRS mobiles, the quality control is practically absent. The GMRS-V1 is apparently alright and Part 95 accepted. Use CHIRP for programming; it will save a lot of time and headaches, while allowing for named channels.
     
    When buying a used radio online, make sure the frequency range actually includes 462-468 MHz. For handheld radios, make sure that you are getting (or already have) a charger and antenna. The battery is probably shot, so include a replacement in your budgeting. I like to have at least one spare battery, so I can continue using the radio while a battery is charging. Don't transmit on a handheld radio while it's charging.
     
    Counterfeit antennas are a thing, especially with Nagoya. Buy from trusted sources, or find a friend with an antenna analyzer or VNA who'd be willing to show you how to see if an antenna is good or trash. Be willing to learn how to use test equipment, or at least be aware of what that test equipment is testing. It'll help greatly in the future when you are faced with new problems.
     
    GMRS isn't ham radio, but it's often used pretty similarly to 70cm. Ham radio clubs are still a useful resource where you can make lots of friends with lots of knowledge. If you don't have a ham license, they'll pressure you to get one. A Technician-class license is easy to get, costs much less than your GMRS license, and you may even be able to use the same antenna for 70cm. Different clubs have different focuses, so don't get discouraged if you don't feel a particular club is right for you. Depending on the area, hams may not like GMRS for one reason or another; but recognize the common interest in establishing reliable communications between licensed operators.
     
    There's a 30 MHz gap between 70cm and GMRS, so most 70cm antennas with appreciable gain don't work on GMRS (and remember you're usually transmitting at 467 MHz, not 462 MHz). Check your antenna's documentation to see how much bandwidth you have. Most handheld antennas are broadband enough, and most commercial-band antennas actually work better on GMRS.
     
    Don't put up a repeater until you know exactly what you're doing. There's enough deaf GMRS repeaters out there. Don't take on the task alone, either. The more support you have, the better (and, for you, cheaper) the repeater can be. Even a low hilltop provides significantly more coverage than a rooftop repeater. Sites cost money, but can cost a heck of a lot less if you get to know some repeater folk and can make a good sales pitch. Don't use LMR-400 for repeaters.
     
    Getting above the roofline makes a big difference in suburban areas, particularly when trying to work hilltop sites. For more rural areas, try to get above the treeline if possible. If you're the only one-story house in a block of two-story houses, ouch.
     
    Be it ham radio or GMRS, remember that the radio hobby is about communication. This includes, but is not limited to: rag chewing, technical talk, emergency communication, repeater building, proselytizing the wonders of properly configured radios, and being willing to help the confused. A lot of people out there try to assert their dominance over a channel and run around with a better-than-thou mentality, and over the course of your license you'll find at least one of them. They aren't out to improve either service or what each service stands for, so stay away from them. Don't let them change your perception of the radio hobby, either.
     
    If you hear confused FRS users on channel 1 that can't get their radios to talk to each other, offer to help. Transmit CTCSS 67.0 and receive CSQ. They'll probably need help configuring CTCSS on their radios. Ask for the model number and look up the manual on Google. Stuff like this happens more often than I'd like to admit, and half the time those people spent a lot of money on those radios. Be a good citizen.
     
    Some repeaters will beacon out their callsign. That doesn't mean there's anyone using it. Repeaters aren't supposed to do that, but not everyone has a good repeater controller. It's almost universally agreed upon that such repeater behavior is super annoying.
     
    Not all repeaters identify, and that can make it a pain in the rear to figure out who owns the repeater. It's usually private repeaters that don't identify, and some legally don't even have to. It's another fact of life that makes frequency coordination difficult for repeater owners.
     
    The FRS channels, especially 1-14, are flooded with business users. They're allowed to be there, and aren't looking for conversation. Let them be. They're close enough together (a few hundred feet, typically) that they won't even notice you're on the same frequency as long as you're on a different CTCSS/DCS code.
     
    Not everyone is following the rules. Report egregious violators to the FCC, but don't expect enforcement action. Report criminal activity (eg. terroristic threats, use of radios in a crime) to law enforcement, not the FCC. If you happen to know who the perps are, tell the FCC as well. You probably won't encounter any such activity.
     
    If you start getting involved in the commercial radio users crowd, be it on 70cm or GMRS, you'll see a lot of brand loyalty. I'm a Motorola guy, since those are the first commercial radios I got involved with and those radios meet all of my needs. We have a lot of Kenwood folk on here, and boy do they love their TK-880s. Both make rock-solid commercial radios. There's other brands out there, too. Stay away from cheap Chinese radios, those are markedly not rock-solid radios and may not have any type-acceptance whatsoever. It's generally accepted that radios with commercial (Part 90) type acceptance are fine for GMRS (Part 97E) operation, since Part 90 requirements are more stringent in terms of RF performance. While the FCC is yet to make an official exemption, they allude to it frequently in the 2017 rule change discussion.
     
    Directional antennas (mostly Yagis or log-periodic antennas at these fequencies) are terrible general purpose antennas, since you need to know the direction towards the stuff you want to talk to. Commercial omnidirectional antennas covering 460-470 MHz at a minimum make the best general-purpose antennas. Browning's BR6157 is a good starter antenna, with some gain and a wide bandwidth. If you spend more than $60 on one before any sales tax, you've overspent.
     
    Use FakeSpot when shopping for radios or accessories on Amazon. Don't get ripped off by fake reviews.
     
    Monitor channel 1 (again, transmit CTCSS 67.0 and receive CSQ) during disasters. You may save someone's life. Prioritize your safety highest; you're still a victim.
     
    Don't be a dillweed on the air that hides from consequences behind a microphone; respect is reciprocal. Not everyone you'll meet understands this.
     
    When you got your GMRS license, your whole family just became GMRS licensees as well. Come up with a separate simplex channel for them and them only. It's useful when outdoors, communication between vehicles on road trips, or during disasters. Having a nationwide license to operate a radio without frequency coordination, and with unlicensed operators on FRS, is a beautiful luxury we have on GMRS that you will get nowhere else. Make sure to test your channels ahead of time, and check them regularly if you don't use them often.
     
    I mentioned it earlier, but I'll elaborate on it: RTL-SDR is an excellent tool for GMRS. All of the output channels are visible with a spectrum analyzer-type visualization. Interference becomes easy to spot and identify. CTCSS and DCS decoding is straightforward and nearly instant, and works with hardly any signal strength at all. Signal strength readings can be calibrated against an absolute scale (dBm), which allows for comparison between antennas and locations. A fancy setup of them, Kerberos SDR, can do direction finding with real-time map plotting, but requires some technical knowledge. SDR is fairly recent, and there's plenty of user groups online (like Reddit's r/RTLSDR). When shopping for RTL-SDR, don't spend more than $30 for a bare unit, and don't buy anything that doesn't have a 1.0ppm TCXO or better. If the item description doesn't say TCXO, it doesn't have one.  RTL-SDR Blog v3 is a good unit, and the Nooelec NESDR SMArTee performs the same. Throw the RTL-SDR Blog 20dB LNA on there as well, life will be much better. Use a USB 2.0 extension cord with SDRs.
     
    Talking on a handheld radio while driving a vehicle is illegal in California under the cell phone laws. Mobiles, with a simple PTT-only hand mic, are fine.
     
    Don't get a 16 or 48 channel radio as your first real commercial or commercial-grade radio. Go for something with at least 128 channels and a screen. Get the programming software and cable before you get the radio so you aren't stuck with a paperweight. Don't give money to HamFiles.
     
    If you have a lot of long conversations but all you have is your handheld radio, get a mobile radio and a power supply. Use a proper antenna (as discussed earlier) and some low-loss coax (RG-8, LMR-240, or better). PL-259/SO-239, also called the UHF connector, is a terrible connector at UHF. Avoid it wherever possible. Use TNC or N for permanent or semi-permanent connections, and BNC for connections you switch out a lot. Keep your connectors clean and seal any outdoor terminations. Assume each adapter adds 0.5-1dB of loss, so use as few adapters as possible. Get your coax terminated in whatever connector your antenna has; don't leave the adapter outdoors. Mastic tape gums up over time and future you will hate present you. If you use cheap non-outdoors coax like I did, it can get water ingress. SWR will still show a rather normal reading, but the wet insulator will suck up all your RF (easily 99% of it).
     
    Good coax is thicker than you think. Take that into consideration.
     
    Folk at your local ham radio club, or GMRS club if you live in an area with one, have done enough fixed radio installations to be able to help you with yours. Don't go out alone and do it, but take some notes so you can eventually help others. Honestly, they're not that hard.
     
    If you're in a place that gets thunderstorms more than a few times a year, lightning protection is a real concern. Nothing will stop a direct strike, so unplug your equipment during such inclement weather. That's another reason to keep portable radios around.
     
    Repeaters almost always use hardline instead of flexible coax. Hardline is expensive and requires special tools. Good feedline is critical on repeaters because you usually have a 40-watt transmitter on the same antennas as a sensitive receiver. Slight non-linear effects, even a rusty fencepost nearby, can cause issues with receiver performance.
     
    If you have an opportunity to visit a hilltop repeater site (an opportunity you may get if you're involved with repeater groups), take it. The first trip to one is an experience, and you'll get to see a variety of real-world installations. Hilltop sites are surprisingly dirty; nobody's up there keeping the floors clean. Some sites are cleaner than others. It's often a long drive and fair distance from civilization, so bring a lunch and go to the bathroom before the trip. Some sites require four-wheel drive and an experienced driver to get to. Buy their dinner.
     
    Flat areas can get significant coverage from a low-level repeater. Rooftop repeaters actually have decent performance in those environments.
     
    Even on rooftop antennas, your simplex range to a five-watt mobile/portable can be as short as two miles. GMRS is heavily influenced by line-of-sight propagation. Building penetration is better than MURS or 2-meters. 
  2. Like
    WRAF213 got a reaction from kipandlee in Waterprofroofing a two piece antenna.   
    I've gone through enough Flex-Shot to name a radio after it.
  3. Like
    WRAF213 got a reaction from marcspaz in Not sure how many are on here who know or help with Cqsanta.com   
    "Ham radio really starts at HF" is an old-fashioned view of a dynamic hobby. Every operator I have talked to who shares that "ham radio really starts at HF" view has told me some variation of "I can't possibly sit around on a 2-meter repeater, talking to the same people every day." VHF and UHF operation have evolved rapidly this decade (first with Wouxun and Baofeng, then with entry-level radios featuring digital voice), while HF has lagged behind. Nearly all of the development on HF since 2005 has targeted high-end radios, outside the scope of what new operators will be using to experience HF for the first or second time; it's about upselling the existing products, not creating a product less expensive for the consumers. IP linking of both analog and digital VHF/UHF systems have whittled away at HF's advantages for ragchew, all while requiring much less equipment investment. You'll hear "the magic isn't there", but that's from a lack of understanding of the underlying infrastructure that all has to work together to establish that connection.
     
    Ham radio can start anywhere. It could be on your local 2-meter repeater where a high-school student studied for their Technician license and bought an Anytone handheld to celebrate getting their first callsign. It could start with an unlicensed operator using their grandfather's radio under their supervision and callsign. It could start where my journey started, on someone else's HF receiver. It could start on a DMR hotspot, a satellite, a fresh-built uBITX, or even a packet node. But for most people entering the hobby, it's going to be on your local 2-meter repeater. Anyone who says that isn't really ham radio has lost sight of the hobby's goal.
  4. Like
    WRAF213 got a reaction from ratkin in Digital in GMRS - which mode is most appropriate?   
    Here's some excerpts from the FCC's 2017 rule change discussion:
     
     
     
     
     
     
    The only way I see digital voice happening on GMRS is by creating a new service that's like GMRS but not, and digitizing from the start; type-certified equipment from the 1960s is probably still in use today, and there's no reason to fix what ain't broke.
     
     
    But since we're speaking purely in hypotheticals here:
    On the day pigs fly and there's a NPRM for digital voice (which is probably going to be a easily licensed 6.25 kHz modulation not common in commercial equipment (dPMR)), we suggest this as a rule: 462.675 MHz with a 141.3 Hz subaudible tone is officially recommended as a traveler's information channel, and no digital is allowed in the 25 kHz band centered at 462.675 MHz?
     
    In reality, I would expect more digital voice exclusions, since analog repeaters would receive interference from any of four ultra-narrowband channels. It will actually have the effect of further overcrowding already overcrowded channels, since the new equipment will be purely interference to all existing equipment and only unidirectionally interoperable in the best case. To properly monitor the analog side, the ultra-narrowband receivers would need to either switch rapidly between the narrowband channel center on a 12.5 kHz step, and the ultra-narrowband channel center on a 6.25 kHz step, requiring a complicated and fairly expensive receive structure that would introduce additional confusion for the licensed-by-rule family members covered under the licensee's callsign. GMRS is already complicated enough, given the FRS/GMRS combination radio debacle. There's a whole list of reasons why DV, regardless of bandwidth, will never happen.
  5. Like
    WRAF213 got a reaction from ratkin in Digital in GMRS - which mode is most appropriate?   
    DCDM is part of the standard, but standardization isn't the problem. DCDM requires infrastructure, specifically a timing master, in order to keep units synchronized. Handhelds are capable of being the timing master, but their range is poor and the necessary beaconing will drain the batteries. DCDM does not work on mixed systems because there is no way to guarantee there's just one station claiming timing master. In effect, timeslots can't be established on the nationwide, uncoordinated channels that GMRS has. The signaling a repeater uses to establish timeslots is embedded between each timeslot. TDMA transmitters (either on the repeater's input or in simplex mode) don't transmit during that period, since that's a guard period between transmissions.
    In TDMA direct mode, an elected channel timing leader MS shall establish the timing reference for both time slots on the frequency. MS units that are not the channel timing leader are responsible for retransmitting the timing reference out to the edge of the wide area system. This mechanism helps to ensure that all MS units in the wide area system are working from the same timing reference. In general a MS transmits in the appropriate slot with the channel slot timing established by the channel timing leader MS. I was making specific reference to the post-2017 laws. What you're saying in that last post isn't consistent with what you said in your first post (P25 is obsolete vs. P25 offers nothing analog+DTMF can). P25 Phase 1 is still the ONLY P25 format for conventional operation, and it will be some time before we see any format include true direct-mode timeslotting. The hidden-node problem would prevent a radio from using whatever voice traffic it hears out there as a timing master. Solving that would require GPS timeslot edge references (not unattainable with current technology), which would increase equipment costs up to the public-safety realm. I don't think very many of us bought our radios new from a dealer, so we wouldn't be the market for it. Equipment cost is a real concern when the issue of FRS interoperability is introduced; it's still a band for toy radios for your kids.
     
    P25 runs the vocoder at a higher rate than DMR, and equivalently has a higher data rate (7200bps vs. 3600bps after ECC). Yes, the vocoder is inferior, but it still fits in more voice information. Of course wideband FM is better, but that isn't what the topic is about. All digital voice modes will exceed narrowband FM at decode threshold, that's one of the biggest advantages of using digital voice and isn't an advantage of any one format. DMR uses less power for the same signal but only half of the channel's bandwidth can be realized.
     
    This whole thread is just an example of why we'll be using analog for the next twenty years.
  6. Like
    WRAF213 got a reaction from ratkin in Program TYT 8000E radio to a Repeaters   
    It's only Part 15 certified so it should only be used in the ham bands. Since the transmitter doesn't have any type acceptance, it's probably spitting spurs out everywhere (cross-band repeat is particularly notorious). Don't use it on GMRS.
     
    The transceiver is designed [poorly] for the 400-520 MHz range, so it won't be a radio performance issue. It's an RDA1846 based design so there's not a lot of front-end variability to worry about.
     
    Anyways, make sure you have the correct repeater offset of +5 MHz. Some repeaters don't send a CTCSS tone on the tail, so check the busy-channel LED to see if anything is coming back. In frequency display mode, you should see the working frequency change from 462.xxxx to 467.xxxx when keyed up.
     
    Find a different radio for this band. Part 95 certification is ideal but Part 90 is close enough. If it doesn't have either of those, don't spend money on it.
  7. Like
    WRAF213 got a reaction from mainehazmt in The definitive CCR thread... why you won't really save anything.   
    But it's important to realize when it's not practical to pay for more selectivity. Good commercial handhelds have enough selectivity to allow full-duplex operation by one operator, with a few feet of antenna separation. Good mobiles do better than that. If that's not enough desense protection, there's other issues at play. There's no improvement to be made if there isn't an issue, so it's just wasted money and/or lost functionality.
     
    CCRs work just fine as transceivers for 99% of the population. Yes, they don't work in the busy RF environments found at an enthusiast's base station, a command post, or when working near other operators on different in-band channels. They're cheap, show people what the hobby can offer, and include a lot of features (like FPP and ridiculous channel capacity) that new operators need to find their niche within the hobby and understand what parameters need to be configured to operate cleanly on someone else's system. And when they break (probably due to a novice operator blowing out the finals or dropping it), it's not a big investment being lost. They exist in the market for a reason: because they do work, unlike what the topic's title implies. They wouldn't sell if they didn't. It's important to understand their limitations, but they're not as severe as you're making it out to be.
  8. Like
    WRAF213 got a reaction from ratkin in The definitive CCR thread... why you won't really save anything.   
    The SLR8000 is a terrible benchmark to use since NOBODY is using that as their primary GMRS radio, particularly as a mobile or portable (nor is it Part 95 type accepted). Repeaters are expected to have excellent desense rejection since they're usually running a 25-40 watt transmitter on the same antenna as the receiver. A lot of the nicer handheld radios have tracking filters on the frontend that gives them stronger desense protection, and you won't find that feature at the CCR price point. You get what you pay for; don't forget the cost of a new commercial radio.
  9. Like
    WRAF213 got a reaction from Ian in The definitive CCR thread... why you won't really save anything.   
    Yes, I'd like to see how the tests were done. At best, it's demonstrating adjacent channel selectivity and receiver sensitivity. It's also generalizing all CCRs into the GD-77, which is quite reckless. So, we're trying to point out that these radios are junk, yet trusting the totally-not-copied-and-pasted selectivity measurements the manufacturer provided? Is repeater selectivity measured with cavity filters installed? If your noise floor is -50dBm you should be getting cooked alive.
     
    One odd point to mention is that a dBu to dBm conversion isn't as straightforward as it sounds since a lot of handheld radios (especially CCRs) don't present exactly 50 ohms at the antenna.
     
    I played around with a service monitor and found that my Connect Systems CS-580 had a receiver that was hotter than any of my commercial radios, and it also has a proper 12.5 kHz channel bandwidth for the narrowband setting (which doesn't really matter since I bet you're using it in wideband anyways).
     
    For a well designed receiver, selectivity is a compromise with sensitivity. You can add preselectors and tracking filters, but all of those add insertion loss, which contributes to noise figure. Most CCRs run nearly naked, so the frontend-on-a-chip is exposed behind only a LNA and probably some highpass filters. They can get very sensitive, but this leaves them prone to desense from signals not necessarily near the receiver's frequency. Either way, desense is more complicated than this graph can show.
  10. Like
    WRAF213 got a reaction from Ian in Why "More Power" Isn't The Answer   
    Yeah, being within that distance of a broadcaster is the real problem at hand. Based on your symptoms, I'm assuming there's UHF TV broadcast on that tower in the 500 MHz band (which is almost all that's left of UHF TV). TV typically runs tens to hundreds of kilowatts, and any internal or external mixing products of TV broadcast may resemble noise due to the DTV modulation. FM is more easily controlled and the harmonics aren't in-band (fourth harmonic ends at 432.2 MHz), but that still requires strong filtering. To do an actual check of your RF environment and noise floor, you'd need a good spectrum analyzer that stays linear up to at least 10dBm; most quality equipment is rated up to +30dBm.
     
    If you've got noise that appears to be in-band but cavity filters improve the situation, you've probably got intermod going on. Band-reject filters near the antenna can help with that. If filtering near the receiver doesn't improve in-band performance to a satisfactory level, PIM may be at play. Right now, intermod and overload effects could mask a generally crap noise floor from unintentional radiators; don't expect to dive in with hundreds of dollars of equipment and hit thermal noise floor (though you'll have to spend a little bit more to avoid PIM and ensure linearity of any active components). A noise power of -125dBm/16 kHz is pretty typical for a quiet area, compared to thermal noise floor at -131dBm/16 kHz. HDMI/DVI are particularly egregious noisemakers on UHF LMR bands, especially with AliExpress-quality cables. LMR-400 would make a mess of your RF environment.
     
    Overload effects don't cause CCRs to not be heard, it simply knocks out their ability to hear. Any RDA1846 design will show desense on almost any rooftop antenna anyways; they're meant to be used with unity-gain antennas attached to the unit and work rather well in that scenario. Desense on the stock antenna or equivalent is only encountered in rather exceptional RF environments.
  11. Like
    WRAF213 got a reaction from Marius1195 in Why "More Power" Isn't The Answer   
    Absolutely, finding higher ground should be the first step towards improving a setup. Running more power only matters on fixed setups where the antenna is already as good as it can get, or on mobile operation where there is no 'finding a good spot'. Even then, there's not a huge difference between 15 and 40 watts.
     
    Here's my first piece of advice for new users (and I have a bunch, fair warning): use scan mode on a radio that will tell you the active CTCSS tone or DCS code if you're looking for repeaters to use. RTL-SDR is also a good tool, and makes the entire 462 MHz band visible with good sensitivity and excellent selectivity.
     
    Especially on fixed setups, grounding is important. Noise will get picked up along the coax and travel up to the antenna, where it enters the receiver. The effect is very apparent on SDRs, where the noise floor is directly visible. When grounding a setup, check for ground loops with a multimeter.
     
    Learn to recognize the busy-channel indicator on your radio. When the radio detects any activity on the channel, regardless of correct CTCSS/DCS, it'll turn on the busy-channel indicator. It'll help you to know if you have the correct CTCSS/DCS for a particular system. Some repeaters use multiple CTCSS/DCS, so this indicator can be useful on those repeaters to make sure you aren't interfering with a different conversation. On Baofeng's radios, this is the green LED on top of the radio. On Motorola's commercial radios, this is a blinking red or green LED near the antenna; on their FRS/GMRS radios, this is the red LED above the display.
     
    Some repeaters transmit CTCSS/DCS back to you, but only while someone is transmitting to it. If you're hitting the repeater but can't hear it come back to you once you finish transmitting, this could be a possible cause. Use the monitor feature on your radio or check the busy-channel indicator to check for the repeater's tail.
     
    Don't be afraid to try simplex. If you hear a callsign with variable signal strength, they're probably not going through a repeater. It's rare to find contacts that way, but that's largely because hardly anyone calls for contacts on simplex. 462.5625 (channel 1), transmit and receive CSQ; and 462.6750 (channel 20), transmit CTCSS 141.3 and receive CSQ are good places to try calling CQ.
     
    People who use MDC-1200 on their radios don't actually have to hear the data bursts, the radio can detect the burst and mute it. It gets annoying so most people with MDC-1200 radios have their radios like that.
     
    This forum sure does love their Kenwood TK-880s and Motorola M1225s. They're great radios, but terrible general-purpose radios. Virtually all commercial radios can only be programmed by computer software, so you have to know ahead of time what you're going to talk to. Speaking of commercial radios, used Motorola HT1000 radios are incredibly durable and inexpensive. They use the same programming
     
    Don't waste your money on the BTech GMRS mobiles, the quality control is practically absent. The GMRS-V1 is apparently alright and Part 95 accepted. Use CHIRP for programming; it will save a lot of time and headaches, while allowing for named channels.
     
    When buying a used radio online, make sure the frequency range actually includes 462-468 MHz. For handheld radios, make sure that you are getting (or already have) a charger and antenna. The battery is probably shot, so include a replacement in your budgeting. I like to have at least one spare battery, so I can continue using the radio while a battery is charging. Don't transmit on a handheld radio while it's charging.
     
    Counterfeit antennas are a thing, especially with Nagoya. Buy from trusted sources, or find a friend with an antenna analyzer or VNA who'd be willing to show you how to see if an antenna is good or trash. Be willing to learn how to use test equipment, or at least be aware of what that test equipment is testing. It'll help greatly in the future when you are faced with new problems.
     
    GMRS isn't ham radio, but it's often used pretty similarly to 70cm. Ham radio clubs are still a useful resource where you can make lots of friends with lots of knowledge. If you don't have a ham license, they'll pressure you to get one. A Technician-class license is easy to get, costs much less than your GMRS license, and you may even be able to use the same antenna for 70cm. Different clubs have different focuses, so don't get discouraged if you don't feel a particular club is right for you. Depending on the area, hams may not like GMRS for one reason or another; but recognize the common interest in establishing reliable communications between licensed operators.
     
    There's a 30 MHz gap between 70cm and GMRS, so most 70cm antennas with appreciable gain don't work on GMRS (and remember you're usually transmitting at 467 MHz, not 462 MHz). Check your antenna's documentation to see how much bandwidth you have. Most handheld antennas are broadband enough, and most commercial-band antennas actually work better on GMRS.
     
    Don't put up a repeater until you know exactly what you're doing. There's enough deaf GMRS repeaters out there. Don't take on the task alone, either. The more support you have, the better (and, for you, cheaper) the repeater can be. Even a low hilltop provides significantly more coverage than a rooftop repeater. Sites cost money, but can cost a heck of a lot less if you get to know some repeater folk and can make a good sales pitch. Don't use LMR-400 for repeaters.
     
    Getting above the roofline makes a big difference in suburban areas, particularly when trying to work hilltop sites. For more rural areas, try to get above the treeline if possible. If you're the only one-story house in a block of two-story houses, ouch.
     
    Be it ham radio or GMRS, remember that the radio hobby is about communication. This includes, but is not limited to: rag chewing, technical talk, emergency communication, repeater building, proselytizing the wonders of properly configured radios, and being willing to help the confused. A lot of people out there try to assert their dominance over a channel and run around with a better-than-thou mentality, and over the course of your license you'll find at least one of them. They aren't out to improve either service or what each service stands for, so stay away from them. Don't let them change your perception of the radio hobby, either.
     
    If you hear confused FRS users on channel 1 that can't get their radios to talk to each other, offer to help. Transmit CTCSS 67.0 and receive CSQ. They'll probably need help configuring CTCSS on their radios. Ask for the model number and look up the manual on Google. Stuff like this happens more often than I'd like to admit, and half the time those people spent a lot of money on those radios. Be a good citizen.
     
    Some repeaters will beacon out their callsign. That doesn't mean there's anyone using it. Repeaters aren't supposed to do that, but not everyone has a good repeater controller. It's almost universally agreed upon that such repeater behavior is super annoying.
     
    Not all repeaters identify, and that can make it a pain in the rear to figure out who owns the repeater. It's usually private repeaters that don't identify, and some legally don't even have to. It's another fact of life that makes frequency coordination difficult for repeater owners.
     
    The FRS channels, especially 1-14, are flooded with business users. They're allowed to be there, and aren't looking for conversation. Let them be. They're close enough together (a few hundred feet, typically) that they won't even notice you're on the same frequency as long as you're on a different CTCSS/DCS code.
     
    Not everyone is following the rules. Report egregious violators to the FCC, but don't expect enforcement action. Report criminal activity (eg. terroristic threats, use of radios in a crime) to law enforcement, not the FCC. If you happen to know who the perps are, tell the FCC as well. You probably won't encounter any such activity.
     
    If you start getting involved in the commercial radio users crowd, be it on 70cm or GMRS, you'll see a lot of brand loyalty. I'm a Motorola guy, since those are the first commercial radios I got involved with and those radios meet all of my needs. We have a lot of Kenwood folk on here, and boy do they love their TK-880s. Both make rock-solid commercial radios. There's other brands out there, too. Stay away from cheap Chinese radios, those are markedly not rock-solid radios and may not have any type-acceptance whatsoever. It's generally accepted that radios with commercial (Part 90) type acceptance are fine for GMRS (Part 97E) operation, since Part 90 requirements are more stringent in terms of RF performance. While the FCC is yet to make an official exemption, they allude to it frequently in the 2017 rule change discussion.
     
    Directional antennas (mostly Yagis or log-periodic antennas at these fequencies) are terrible general purpose antennas, since you need to know the direction towards the stuff you want to talk to. Commercial omnidirectional antennas covering 460-470 MHz at a minimum make the best general-purpose antennas. Browning's BR6157 is a good starter antenna, with some gain and a wide bandwidth. If you spend more than $60 on one before any sales tax, you've overspent.
     
    Use FakeSpot when shopping for radios or accessories on Amazon. Don't get ripped off by fake reviews.
     
    Monitor channel 1 (again, transmit CTCSS 67.0 and receive CSQ) during disasters. You may save someone's life. Prioritize your safety highest; you're still a victim.
     
    Don't be a dillweed on the air that hides from consequences behind a microphone; respect is reciprocal. Not everyone you'll meet understands this.
     
    When you got your GMRS license, your whole family just became GMRS licensees as well. Come up with a separate simplex channel for them and them only. It's useful when outdoors, communication between vehicles on road trips, or during disasters. Having a nationwide license to operate a radio without frequency coordination, and with unlicensed operators on FRS, is a beautiful luxury we have on GMRS that you will get nowhere else. Make sure to test your channels ahead of time, and check them regularly if you don't use them often.
     
    I mentioned it earlier, but I'll elaborate on it: RTL-SDR is an excellent tool for GMRS. All of the output channels are visible with a spectrum analyzer-type visualization. Interference becomes easy to spot and identify. CTCSS and DCS decoding is straightforward and nearly instant, and works with hardly any signal strength at all. Signal strength readings can be calibrated against an absolute scale (dBm), which allows for comparison between antennas and locations. A fancy setup of them, Kerberos SDR, can do direction finding with real-time map plotting, but requires some technical knowledge. SDR is fairly recent, and there's plenty of user groups online (like Reddit's r/RTLSDR). When shopping for RTL-SDR, don't spend more than $30 for a bare unit, and don't buy anything that doesn't have a 1.0ppm TCXO or better. If the item description doesn't say TCXO, it doesn't have one.  RTL-SDR Blog v3 is a good unit, and the Nooelec NESDR SMArTee performs the same. Throw the RTL-SDR Blog 20dB LNA on there as well, life will be much better. Use a USB 2.0 extension cord with SDRs.
     
    Talking on a handheld radio while driving a vehicle is illegal in California under the cell phone laws. Mobiles, with a simple PTT-only hand mic, are fine.
     
    Don't get a 16 or 48 channel radio as your first real commercial or commercial-grade radio. Go for something with at least 128 channels and a screen. Get the programming software and cable before you get the radio so you aren't stuck with a paperweight. Don't give money to HamFiles.
     
    If you have a lot of long conversations but all you have is your handheld radio, get a mobile radio and a power supply. Use a proper antenna (as discussed earlier) and some low-loss coax (RG-8, LMR-240, or better). PL-259/SO-239, also called the UHF connector, is a terrible connector at UHF. Avoid it wherever possible. Use TNC or N for permanent or semi-permanent connections, and BNC for connections you switch out a lot. Keep your connectors clean and seal any outdoor terminations. Assume each adapter adds 0.5-1dB of loss, so use as few adapters as possible. Get your coax terminated in whatever connector your antenna has; don't leave the adapter outdoors. Mastic tape gums up over time and future you will hate present you. If you use cheap non-outdoors coax like I did, it can get water ingress. SWR will still show a rather normal reading, but the wet insulator will suck up all your RF (easily 99% of it).
     
    Good coax is thicker than you think. Take that into consideration.
     
    Folk at your local ham radio club, or GMRS club if you live in an area with one, have done enough fixed radio installations to be able to help you with yours. Don't go out alone and do it, but take some notes so you can eventually help others. Honestly, they're not that hard.
     
    If you're in a place that gets thunderstorms more than a few times a year, lightning protection is a real concern. Nothing will stop a direct strike, so unplug your equipment during such inclement weather. That's another reason to keep portable radios around.
     
    Repeaters almost always use hardline instead of flexible coax. Hardline is expensive and requires special tools. Good feedline is critical on repeaters because you usually have a 40-watt transmitter on the same antennas as a sensitive receiver. Slight non-linear effects, even a rusty fencepost nearby, can cause issues with receiver performance.
     
    If you have an opportunity to visit a hilltop repeater site (an opportunity you may get if you're involved with repeater groups), take it. The first trip to one is an experience, and you'll get to see a variety of real-world installations. Hilltop sites are surprisingly dirty; nobody's up there keeping the floors clean. Some sites are cleaner than others. It's often a long drive and fair distance from civilization, so bring a lunch and go to the bathroom before the trip. Some sites require four-wheel drive and an experienced driver to get to. Buy their dinner.
     
    Flat areas can get significant coverage from a low-level repeater. Rooftop repeaters actually have decent performance in those environments.
     
    Even on rooftop antennas, your simplex range to a five-watt mobile/portable can be as short as two miles. GMRS is heavily influenced by line-of-sight propagation. Building penetration is better than MURS or 2-meters. 
  12. Like
    WRAF213 got a reaction from Ian in The definitive CCR thread... why you won't really save anything.   
    But it's important to realize when it's not practical to pay for more selectivity. Good commercial handhelds have enough selectivity to allow full-duplex operation by one operator, with a few feet of antenna separation. Good mobiles do better than that. If that's not enough desense protection, there's other issues at play. There's no improvement to be made if there isn't an issue, so it's just wasted money and/or lost functionality.
     
    CCRs work just fine as transceivers for 99% of the population. Yes, they don't work in the busy RF environments found at an enthusiast's base station, a command post, or when working near other operators on different in-band channels. They're cheap, show people what the hobby can offer, and include a lot of features (like FPP and ridiculous channel capacity) that new operators need to find their niche within the hobby and understand what parameters need to be configured to operate cleanly on someone else's system. And when they break (probably due to a novice operator blowing out the finals or dropping it), it's not a big investment being lost. They exist in the market for a reason: because they do work, unlike what the topic's title implies. They wouldn't sell if they didn't. It's important to understand their limitations, but they're not as severe as you're making it out to be.
  13. Like
    WRAF213 got a reaction from PRadio in Does CTCSS ruin GMRS/FRS?   
    Motorola's used 67.0 Hz by default, while Midland's are CSQ by default. Motorola also had an optional Quiet-Talk feature, which requires an additional tone (52 Hz) before transmissions; this went away when they introduced their current Txxx series radios because it didn't work well.
     
    FRS isn't about communicating with everyone else on FRS, it's about selling a set of radios that work together and don't unmute on interfering signals. Look at Midland's "extra channels".
  14. Like
    WRAF213 got a reaction from ratkin in The definitive CCR thread... why you won't really save anything.   
    But it's important to realize when it's not practical to pay for more selectivity. Good commercial handhelds have enough selectivity to allow full-duplex operation by one operator, with a few feet of antenna separation. Good mobiles do better than that. If that's not enough desense protection, there's other issues at play. There's no improvement to be made if there isn't an issue, so it's just wasted money and/or lost functionality.
     
    CCRs work just fine as transceivers for 99% of the population. Yes, they don't work in the busy RF environments found at an enthusiast's base station, a command post, or when working near other operators on different in-band channels. They're cheap, show people what the hobby can offer, and include a lot of features (like FPP and ridiculous channel capacity) that new operators need to find their niche within the hobby and understand what parameters need to be configured to operate cleanly on someone else's system. And when they break (probably due to a novice operator blowing out the finals or dropping it), it's not a big investment being lost. They exist in the market for a reason: because they do work, unlike what the topic's title implies. They wouldn't sell if they didn't. It's important to understand their limitations, but they're not as severe as you're making it out to be.
  15. Like
    WRAF213 got a reaction from ratkin in Why "More Power" Isn't The Answer   
    Yeah, being within that distance of a broadcaster is the real problem at hand. Based on your symptoms, I'm assuming there's UHF TV broadcast on that tower in the 500 MHz band (which is almost all that's left of UHF TV). TV typically runs tens to hundreds of kilowatts, and any internal or external mixing products of TV broadcast may resemble noise due to the DTV modulation. FM is more easily controlled and the harmonics aren't in-band (fourth harmonic ends at 432.2 MHz), but that still requires strong filtering. To do an actual check of your RF environment and noise floor, you'd need a good spectrum analyzer that stays linear up to at least 10dBm; most quality equipment is rated up to +30dBm.
     
    If you've got noise that appears to be in-band but cavity filters improve the situation, you've probably got intermod going on. Band-reject filters near the antenna can help with that. If filtering near the receiver doesn't improve in-band performance to a satisfactory level, PIM may be at play. Right now, intermod and overload effects could mask a generally crap noise floor from unintentional radiators; don't expect to dive in with hundreds of dollars of equipment and hit thermal noise floor (though you'll have to spend a little bit more to avoid PIM and ensure linearity of any active components). A noise power of -125dBm/16 kHz is pretty typical for a quiet area, compared to thermal noise floor at -131dBm/16 kHz. HDMI/DVI are particularly egregious noisemakers on UHF LMR bands, especially with AliExpress-quality cables. LMR-400 would make a mess of your RF environment.
     
    Overload effects don't cause CCRs to not be heard, it simply knocks out their ability to hear. Any RDA1846 design will show desense on almost any rooftop antenna anyways; they're meant to be used with unity-gain antennas attached to the unit and work rather well in that scenario. Desense on the stock antenna or equivalent is only encountered in rather exceptional RF environments.
  16. Like
    WRAF213 got a reaction from ratkin in The definitive CCR thread... why you won't really save anything.   
    Yes, I'd like to see how the tests were done. At best, it's demonstrating adjacent channel selectivity and receiver sensitivity. It's also generalizing all CCRs into the GD-77, which is quite reckless. So, we're trying to point out that these radios are junk, yet trusting the totally-not-copied-and-pasted selectivity measurements the manufacturer provided? Is repeater selectivity measured with cavity filters installed? If your noise floor is -50dBm you should be getting cooked alive.
     
    One odd point to mention is that a dBu to dBm conversion isn't as straightforward as it sounds since a lot of handheld radios (especially CCRs) don't present exactly 50 ohms at the antenna.
     
    I played around with a service monitor and found that my Connect Systems CS-580 had a receiver that was hotter than any of my commercial radios, and it also has a proper 12.5 kHz channel bandwidth for the narrowband setting (which doesn't really matter since I bet you're using it in wideband anyways).
     
    For a well designed receiver, selectivity is a compromise with sensitivity. You can add preselectors and tracking filters, but all of those add insertion loss, which contributes to noise figure. Most CCRs run nearly naked, so the frontend-on-a-chip is exposed behind only a LNA and probably some highpass filters. They can get very sensitive, but this leaves them prone to desense from signals not necessarily near the receiver's frequency. Either way, desense is more complicated than this graph can show.
  17. Like
    WRAF213 got a reaction from Ian in VERO VR-N7500   
    For $200, I'd like to at least have a basic control head, whether it's a detachable head that mounts to the radio or a handheld control head. It's a brick without a working software environment.
  18. Like
    WRAF213 got a reaction from marcspaz in Call sign ID?   
    If there's some ragchew going on and I want in, I'll just jump right in without identifying if it's people I know or people that I know use PTT-ID. Otherwise, I'll wait for a break and give my call suffix (PSG or two-thirteen); then when I get acknowledged, I'll start with my full call. It all depends on the atmosphere of the repeater/group I'm talking to and what level of structure the roundtable has, so I don't interrupt conversation flow when it isn't necessary to go through procedure or get yelled at for quick-keying a comment where a comment procedure is expected.
  19. Like
    WRAF213 got a reaction from RCM in Call sign ID?   
    If there's some ragchew going on and I want in, I'll just jump right in without identifying if it's people I know or people that I know use PTT-ID. Otherwise, I'll wait for a break and give my call suffix (PSG or two-thirteen); then when I get acknowledged, I'll start with my full call. It all depends on the atmosphere of the repeater/group I'm talking to and what level of structure the roundtable has, so I don't interrupt conversation flow when it isn't necessary to go through procedure or get yelled at for quick-keying a comment where a comment procedure is expected.
  20. Like
    WRAF213 reacted to n4gix in So I heard something that sounded like Motobro or DMR.   
    With the limited bandwidth allocated to GMRS, and no repeater coordination at all, it would cause all sorts of grief. Analog and any form of digital simply cannot co-exist within the current 8 channel landscape.
  21. Thanks
    WRAF213 got a reaction from pcradio in Why "More Power" Isn't The Answer   
    Absolutely, finding higher ground should be the first step towards improving a setup. Running more power only matters on fixed setups where the antenna is already as good as it can get, or on mobile operation where there is no 'finding a good spot'. Even then, there's not a huge difference between 15 and 40 watts.
     
    Here's my first piece of advice for new users (and I have a bunch, fair warning): use scan mode on a radio that will tell you the active CTCSS tone or DCS code if you're looking for repeaters to use. RTL-SDR is also a good tool, and makes the entire 462 MHz band visible with good sensitivity and excellent selectivity.
     
    Especially on fixed setups, grounding is important. Noise will get picked up along the coax and travel up to the antenna, where it enters the receiver. The effect is very apparent on SDRs, where the noise floor is directly visible. When grounding a setup, check for ground loops with a multimeter.
     
    Learn to recognize the busy-channel indicator on your radio. When the radio detects any activity on the channel, regardless of correct CTCSS/DCS, it'll turn on the busy-channel indicator. It'll help you to know if you have the correct CTCSS/DCS for a particular system. Some repeaters use multiple CTCSS/DCS, so this indicator can be useful on those repeaters to make sure you aren't interfering with a different conversation. On Baofeng's radios, this is the green LED on top of the radio. On Motorola's commercial radios, this is a blinking red or green LED near the antenna; on their FRS/GMRS radios, this is the red LED above the display.
     
    Some repeaters transmit CTCSS/DCS back to you, but only while someone is transmitting to it. If you're hitting the repeater but can't hear it come back to you once you finish transmitting, this could be a possible cause. Use the monitor feature on your radio or check the busy-channel indicator to check for the repeater's tail.
     
    Don't be afraid to try simplex. If you hear a callsign with variable signal strength, they're probably not going through a repeater. It's rare to find contacts that way, but that's largely because hardly anyone calls for contacts on simplex. 462.5625 (channel 1), transmit and receive CSQ; and 462.6750 (channel 20), transmit CTCSS 141.3 and receive CSQ are good places to try calling CQ.
     
    People who use MDC-1200 on their radios don't actually have to hear the data bursts, the radio can detect the burst and mute it. It gets annoying so most people with MDC-1200 radios have their radios like that.
     
    This forum sure does love their Kenwood TK-880s and Motorola M1225s. They're great radios, but terrible general-purpose radios. Virtually all commercial radios can only be programmed by computer software, so you have to know ahead of time what you're going to talk to. Speaking of commercial radios, used Motorola HT1000 radios are incredibly durable and inexpensive. They use the same programming
     
    Don't waste your money on the BTech GMRS mobiles, the quality control is practically absent. The GMRS-V1 is apparently alright and Part 95 accepted. Use CHIRP for programming; it will save a lot of time and headaches, while allowing for named channels.
     
    When buying a used radio online, make sure the frequency range actually includes 462-468 MHz. For handheld radios, make sure that you are getting (or already have) a charger and antenna. The battery is probably shot, so include a replacement in your budgeting. I like to have at least one spare battery, so I can continue using the radio while a battery is charging. Don't transmit on a handheld radio while it's charging.
     
    Counterfeit antennas are a thing, especially with Nagoya. Buy from trusted sources, or find a friend with an antenna analyzer or VNA who'd be willing to show you how to see if an antenna is good or trash. Be willing to learn how to use test equipment, or at least be aware of what that test equipment is testing. It'll help greatly in the future when you are faced with new problems.
     
    GMRS isn't ham radio, but it's often used pretty similarly to 70cm. Ham radio clubs are still a useful resource where you can make lots of friends with lots of knowledge. If you don't have a ham license, they'll pressure you to get one. A Technician-class license is easy to get, costs much less than your GMRS license, and you may even be able to use the same antenna for 70cm. Different clubs have different focuses, so don't get discouraged if you don't feel a particular club is right for you. Depending on the area, hams may not like GMRS for one reason or another; but recognize the common interest in establishing reliable communications between licensed operators.
     
    There's a 30 MHz gap between 70cm and GMRS, so most 70cm antennas with appreciable gain don't work on GMRS (and remember you're usually transmitting at 467 MHz, not 462 MHz). Check your antenna's documentation to see how much bandwidth you have. Most handheld antennas are broadband enough, and most commercial-band antennas actually work better on GMRS.
     
    Don't put up a repeater until you know exactly what you're doing. There's enough deaf GMRS repeaters out there. Don't take on the task alone, either. The more support you have, the better (and, for you, cheaper) the repeater can be. Even a low hilltop provides significantly more coverage than a rooftop repeater. Sites cost money, but can cost a heck of a lot less if you get to know some repeater folk and can make a good sales pitch. Don't use LMR-400 for repeaters.
     
    Getting above the roofline makes a big difference in suburban areas, particularly when trying to work hilltop sites. For more rural areas, try to get above the treeline if possible. If you're the only one-story house in a block of two-story houses, ouch.
     
    Be it ham radio or GMRS, remember that the radio hobby is about communication. This includes, but is not limited to: rag chewing, technical talk, emergency communication, repeater building, proselytizing the wonders of properly configured radios, and being willing to help the confused. A lot of people out there try to assert their dominance over a channel and run around with a better-than-thou mentality, and over the course of your license you'll find at least one of them. They aren't out to improve either service or what each service stands for, so stay away from them. Don't let them change your perception of the radio hobby, either.
     
    If you hear confused FRS users on channel 1 that can't get their radios to talk to each other, offer to help. Transmit CTCSS 67.0 and receive CSQ. They'll probably need help configuring CTCSS on their radios. Ask for the model number and look up the manual on Google. Stuff like this happens more often than I'd like to admit, and half the time those people spent a lot of money on those radios. Be a good citizen.
     
    Some repeaters will beacon out their callsign. That doesn't mean there's anyone using it. Repeaters aren't supposed to do that, but not everyone has a good repeater controller. It's almost universally agreed upon that such repeater behavior is super annoying.
     
    Not all repeaters identify, and that can make it a pain in the rear to figure out who owns the repeater. It's usually private repeaters that don't identify, and some legally don't even have to. It's another fact of life that makes frequency coordination difficult for repeater owners.
     
    The FRS channels, especially 1-14, are flooded with business users. They're allowed to be there, and aren't looking for conversation. Let them be. They're close enough together (a few hundred feet, typically) that they won't even notice you're on the same frequency as long as you're on a different CTCSS/DCS code.
     
    Not everyone is following the rules. Report egregious violators to the FCC, but don't expect enforcement action. Report criminal activity (eg. terroristic threats, use of radios in a crime) to law enforcement, not the FCC. If you happen to know who the perps are, tell the FCC as well. You probably won't encounter any such activity.
     
    If you start getting involved in the commercial radio users crowd, be it on 70cm or GMRS, you'll see a lot of brand loyalty. I'm a Motorola guy, since those are the first commercial radios I got involved with and those radios meet all of my needs. We have a lot of Kenwood folk on here, and boy do they love their TK-880s. Both make rock-solid commercial radios. There's other brands out there, too. Stay away from cheap Chinese radios, those are markedly not rock-solid radios and may not have any type-acceptance whatsoever. It's generally accepted that radios with commercial (Part 90) type acceptance are fine for GMRS (Part 97E) operation, since Part 90 requirements are more stringent in terms of RF performance. While the FCC is yet to make an official exemption, they allude to it frequently in the 2017 rule change discussion.
     
    Directional antennas (mostly Yagis or log-periodic antennas at these fequencies) are terrible general purpose antennas, since you need to know the direction towards the stuff you want to talk to. Commercial omnidirectional antennas covering 460-470 MHz at a minimum make the best general-purpose antennas. Browning's BR6157 is a good starter antenna, with some gain and a wide bandwidth. If you spend more than $60 on one before any sales tax, you've overspent.
     
    Use FakeSpot when shopping for radios or accessories on Amazon. Don't get ripped off by fake reviews.
     
    Monitor channel 1 (again, transmit CTCSS 67.0 and receive CSQ) during disasters. You may save someone's life. Prioritize your safety highest; you're still a victim.
     
    Don't be a dillweed on the air that hides from consequences behind a microphone; respect is reciprocal. Not everyone you'll meet understands this.
     
    When you got your GMRS license, your whole family just became GMRS licensees as well. Come up with a separate simplex channel for them and them only. It's useful when outdoors, communication between vehicles on road trips, or during disasters. Having a nationwide license to operate a radio without frequency coordination, and with unlicensed operators on FRS, is a beautiful luxury we have on GMRS that you will get nowhere else. Make sure to test your channels ahead of time, and check them regularly if you don't use them often.
     
    I mentioned it earlier, but I'll elaborate on it: RTL-SDR is an excellent tool for GMRS. All of the output channels are visible with a spectrum analyzer-type visualization. Interference becomes easy to spot and identify. CTCSS and DCS decoding is straightforward and nearly instant, and works with hardly any signal strength at all. Signal strength readings can be calibrated against an absolute scale (dBm), which allows for comparison between antennas and locations. A fancy setup of them, Kerberos SDR, can do direction finding with real-time map plotting, but requires some technical knowledge. SDR is fairly recent, and there's plenty of user groups online (like Reddit's r/RTLSDR). When shopping for RTL-SDR, don't spend more than $30 for a bare unit, and don't buy anything that doesn't have a 1.0ppm TCXO or better. If the item description doesn't say TCXO, it doesn't have one.  RTL-SDR Blog v3 is a good unit, and the Nooelec NESDR SMArTee performs the same. Throw the RTL-SDR Blog 20dB LNA on there as well, life will be much better. Use a USB 2.0 extension cord with SDRs.
     
    Talking on a handheld radio while driving a vehicle is illegal in California under the cell phone laws. Mobiles, with a simple PTT-only hand mic, are fine.
     
    Don't get a 16 or 48 channel radio as your first real commercial or commercial-grade radio. Go for something with at least 128 channels and a screen. Get the programming software and cable before you get the radio so you aren't stuck with a paperweight. Don't give money to HamFiles.
     
    If you have a lot of long conversations but all you have is your handheld radio, get a mobile radio and a power supply. Use a proper antenna (as discussed earlier) and some low-loss coax (RG-8, LMR-240, or better). PL-259/SO-239, also called the UHF connector, is a terrible connector at UHF. Avoid it wherever possible. Use TNC or N for permanent or semi-permanent connections, and BNC for connections you switch out a lot. Keep your connectors clean and seal any outdoor terminations. Assume each adapter adds 0.5-1dB of loss, so use as few adapters as possible. Get your coax terminated in whatever connector your antenna has; don't leave the adapter outdoors. Mastic tape gums up over time and future you will hate present you. If you use cheap non-outdoors coax like I did, it can get water ingress. SWR will still show a rather normal reading, but the wet insulator will suck up all your RF (easily 99% of it).
     
    Good coax is thicker than you think. Take that into consideration.
     
    Folk at your local ham radio club, or GMRS club if you live in an area with one, have done enough fixed radio installations to be able to help you with yours. Don't go out alone and do it, but take some notes so you can eventually help others. Honestly, they're not that hard.
     
    If you're in a place that gets thunderstorms more than a few times a year, lightning protection is a real concern. Nothing will stop a direct strike, so unplug your equipment during such inclement weather. That's another reason to keep portable radios around.
     
    Repeaters almost always use hardline instead of flexible coax. Hardline is expensive and requires special tools. Good feedline is critical on repeaters because you usually have a 40-watt transmitter on the same antennas as a sensitive receiver. Slight non-linear effects, even a rusty fencepost nearby, can cause issues with receiver performance.
     
    If you have an opportunity to visit a hilltop repeater site (an opportunity you may get if you're involved with repeater groups), take it. The first trip to one is an experience, and you'll get to see a variety of real-world installations. Hilltop sites are surprisingly dirty; nobody's up there keeping the floors clean. Some sites are cleaner than others. It's often a long drive and fair distance from civilization, so bring a lunch and go to the bathroom before the trip. Some sites require four-wheel drive and an experienced driver to get to. Buy their dinner.
     
    Flat areas can get significant coverage from a low-level repeater. Rooftop repeaters actually have decent performance in those environments.
     
    Even on rooftop antennas, your simplex range to a five-watt mobile/portable can be as short as two miles. GMRS is heavily influenced by line-of-sight propagation. Building penetration is better than MURS or 2-meters. 
  22. Like
    WRAF213 got a reaction from kipandlee in VERO VR-N7500   
    For $200, I'd like to at least have a basic control head, whether it's a detachable head that mounts to the radio or a handheld control head. It's a brick without a working software environment.
  23. Like
    WRAF213 reacted to berkinet in Digital in GMRS - which mode is most appropriate?   
    I think you may be unfairly characterizing the previous comment. I believe @WRAF213 was quoting the FCC’s own comments as a way of shining light on what might and might not be views and proposals the FCC would be open to entertaining. He did not claim to support or reject those views. 
    My own personal view is that this discussion has pretty much served its purpose and it is now time to let it go before we reach the point of Godwin’s law: https://en.m.wikipedia.org/wiki/Godwin%27s_law
  24. Like
    WRAF213 got a reaction from RCM in Digital in GMRS - which mode is most appropriate?   
    Here's some excerpts from the FCC's 2017 rule change discussion:
     
     
     
     
     
     
    The only way I see digital voice happening on GMRS is by creating a new service that's like GMRS but not, and digitizing from the start; type-certified equipment from the 1960s is probably still in use today, and there's no reason to fix what ain't broke.
     
     
    But since we're speaking purely in hypotheticals here:
    On the day pigs fly and there's a NPRM for digital voice (which is probably going to be a easily licensed 6.25 kHz modulation not common in commercial equipment (dPMR)), we suggest this as a rule: 462.675 MHz with a 141.3 Hz subaudible tone is officially recommended as a traveler's information channel, and no digital is allowed in the 25 kHz band centered at 462.675 MHz?
     
    In reality, I would expect more digital voice exclusions, since analog repeaters would receive interference from any of four ultra-narrowband channels. It will actually have the effect of further overcrowding already overcrowded channels, since the new equipment will be purely interference to all existing equipment and only unidirectionally interoperable in the best case. To properly monitor the analog side, the ultra-narrowband receivers would need to either switch rapidly between the narrowband channel center on a 12.5 kHz step, and the ultra-narrowband channel center on a 6.25 kHz step, requiring a complicated and fairly expensive receive structure that would introduce additional confusion for the licensed-by-rule family members covered under the licensee's callsign. GMRS is already complicated enough, given the FRS/GMRS combination radio debacle. There's a whole list of reasons why DV, regardless of bandwidth, will never happen.
  25. Like
    WRAF213 got a reaction from berkinet in VERO VR-N7500   
    Doing some research, it doesn't have any FCC type acceptance, including Part 15. Shouldn't be allowed to be sold here in the US, but they can be imported solely for amateur radio use and not resold. The only Vero radio I could find certification on was the VR-6600PRO, which is only certified in China for 430-440 MHz on the UHF side. I'm sure transmit is wide open, since there's people using these on 440-450.
     
    Given the size and feature set of that radio, I would be surprised if it weren't an AT1846S chip under the hood, like the BTech UV-25X4.
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