axorlov
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Posts posted by axorlov
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They are more expensive because UHF is more challenging from technical standpoint than 27MHz.
There is a thread here where we were discussing getting SWR meter vs NanoVNA. NanoVNA is much more advanced, and costs less than a good SWR meter, but it much less newbie-friendly. SWR meter worth getting (together with quality UHF-capable dummy load!) if you are doing home or car installs. For HTs, you cannot really use SWR meter to obtain meaningful data.
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Yep, what Radioguy said. Page 26 in Service Manual. https://www.manualslib.com/manual/779398/Kenwood-Tk-880.html Or send me PM with your email, I can send you manual pdf.
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I'd go with Alinco DJ-MD5, that was mentioned above. Being legit (almost, it's Part 90) worth something, no?
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I have to correct myself, when I said 10 times reduction for RG58U I was thinking of 100 ft length of the cable. Still, 50 ft is nothing to sneeze about. Use LMR-400 if possible. It's a 3/8-inch cable, fairly rigid, and depending on how you're going to pull it, it could be a good thing. So, what everybody said, and the calculator provided by JeepCrawler98 is very useful tool. I totally agree. You're putting up Yagi, means you want to put all power you have in a small sector, so makes sense to not waste this power to heat the cable and surroundings.
I, myself, never use RG58U. For car installs, where the cable run is shorter than 10' and I need a thin cable, I tend to use LMR-240. Or RG8X if space is very tight, because it's more robust than LMR type. For home base I'd pull thicker LMR-400. It is a popular cable, available everywhere (I usually buy from DX Engineering, they have 400MAX which is an LMR-400 knock-off with a similar characteristics), connectors for it are no problem, and you can buy correct length with connectors already attached.
And if you're a newbie, you should seriously consider getting cable with connectors. Go to reputable vendor (Antenna Farm, DX Engineering, people will share their favorite places), order pre-made assembly with N connectors if the antenna has N connector on it. You can use N-to-PL259 adapter inside home and keep much better weather-proof N connector outside on the antenna.
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RG58U is a wrong cable to use for 50' length. You reduce power of your signal 10 times. Use LMR-400. Coax attenuation chart: https://www.w4rp.com/ref/coax.html
If you have to have thin cable, at least opt for LMR-240 or RG8X.
- wayoverthere, WROA675 and DeoVindice
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10 minutes ago, haneysa said:
I am looking at the "Line A and Line C" restrictions in part 95E rules. They cite a treaty for the reason for those restrictions. They provide a link to the treaty agreements with Canada. No where in any of the agreements shown on that page do I find an agreement regarding GMRS or FRS frequencies. I know that the Line A and Line C are still shown on the license, but perhaps the actual agreement lapsed or was rescinded, and someone forgot to update the license language? The closest frequencies to GMRS that I found listed were 454-459Mhz and 470-806Mhz. Line A begins 5 miles north of my house, hence the interest. So are these restrictions still in effect?
I'm far from Lane A and Line C, but my take on it, if license states the restriction, and this restriction was never specifically rescinded, it is still active. Just two channels lost, should be no biggie.
Line A, B, C detailed description (you're likely aware of it): https://www.fcc.gov/engineering-technology/electromagnetic-compatibility-division/frequency-coordination-canada-below
For GMRS, my license updated in 2020 still states the restrictions: no transmission on 462.650, 462.700, 467.650, 467.700. There is no mentioning about this restriction in Part 95.
For ham, no transmission in 420-430MHz segment, 97.303(m): https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D/part-97#p-97.303(m)
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There are tones that are susceptible to external interference. The 136.5 is one to avoid. The radio that sends DCS does it at 134.4 baud, and if you have nearby repeater or radio using DSC (no matter which one), your radio may mistakenly think it's 136.5 it's hearing. 110.9 is little too far from the second harmonic of 60Hz, but who knows, tone decoder on your radio may not be tuned properly.
There is a thread here, comment from n1das explains it well:
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Yep, this is why I just set my absolute maximum in my first bid, and never up it. If people want to play games, sure, it's a free country. Or they may need the stuff more than I do. Or they are wealthier than I'm. It's all good.
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Should be Browning 6140, no? 6140 gave me years of very good problem-free performance. It used to sell for the whopping $35, now the cheapest I can find is $50 on amazon and $50 on newegg. If you only need GMRS, I would recommend it over popular Ed Fong antenna for the reasons outlined here on this forum many times. You can use search to read yourself. If you want ham and GMRS, I still would recommend something else over Ed Fong's antenna (Diamond X50). Yes, BR-6140 has female N-connector, so you cable should have male N-Connector on the antenna side. RG8/U would be an ok choice, however do not confuse it with RG8X, which would be much more more lossy, but smaller and easier to handle. RG8X is better suited for short tight runs, like when you are doing car install. LMR-400 is much better choice (two times better than RG8/U or RG213), when we are talking about 50 feet and more. It is also more popular, easier to find everywhere with connectors and without.
Cable attenuation chart: https://w4rp.com/ref/coax.html
Thread here about cables and loss (sadly, pics are stripped):
I tend to buy my cable and connectors from DX Engineering, unless I'm feeling real cheap and adventurous on that particular day, in which case it's ebay.
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3 minutes ago, BoxCar said:
Narrowbanding was mandated for the VHF frequencies below 174 MHz.
It's for both VHF and UHF
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Small tiny correction: narrowbanding was mandated by FCC for the commercial Part 90 radios. GMRS is still wide band. FRS was always narrow band. Midland took easy way, and decided that their offerings will be narrow band. There is some logic in this decision, if you take in account Midland's FRS offerings and desire to make the whole universe of Midland to be compatible with itself. Sure, they made it less compatible with wide band GMRS equimpment, but maybe it's their intent, to lock users in their universe.
- DanW, WRUI504 and wayoverthere
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5 hours ago, MichaelLAX said:
The key phrase here is "FTDI" which is a chip, manufactured by Prolific, inside the head of the USB portion of the cable, that converts serial signals from the HT to USB for the computer to use.
Miklor describes the current situation of many "Baofeng" cables having counterfeit FTDI chips inside them and how to deal with this problem.
Spoiler alert: buy a $22 cable with the genuine Prolific FTDI chip inside or be prepared to spend some time figuring out which driver will work on your cable with its counterfeit chip!
FTDI and Prolific are two different companies. Prolific's popular PL-2303 chip was cloned by no-name Chinese manufactures and sold as genuine in huge amounts, that made Prolific to end-of-life this chip 10 years ago and disable counterfeit chips via Windows driver.
You actually want FTDI chipset in the cable to avoid silly games with Windows drivers. They are more expensive, but they work out of the box. Vast majority of Prolific 2303 chips on the market today are fake. Or buy from proven trusted vendor, like bluemax49s, who uses genuine Prolific chips in his cables. He also exchanges Prolific cables should not they work for your application.
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Good friend had a birthday recently, so I jumped and bought Radioddity GM-N1 as a gift. Thanks for the heads up. The usage mode: outdoors in simplex, in rare forest and mountains. Repeater capacity is not required, but nice to have feature. Wide-band is very much required, for interop with mobiles. Friend has GMRS license.
Today I had a chance to put it against my Kenwood TK-3170 in a quick and dirty way. Meaning, the simplest distance comparison, when Operator 1 is stationary and Operator 2 drives around business parks and residential areas. Both operators had TK-3170 and GM-N1 tuned to the same frequency, wide-band, with the same DPL code. The GM-N1 squelch level was programmed to 2 (out of 10, and the default is 5). Both Kenwoods and Radioddity started to break up and go below 50% availability at about the same range. Direct distance is nothing to write home about: 1.3 miles. But between Operator 1 and Operator 2 there were: 1-story business park, freeway grade, 3-story business park, railroad grade, 1-2 story residential area. Not bad at all, in my book. The noise-cancelling feature apparently is not a total gimmick, it reliably removes static when signal is low. It really helps.
Annoyances:
- There is no way to change any of the programmed parameters on the radio itself. Not possible to change tones, squelch, and frequencies (FCC forbid). Not possible to add or remove channels from scan.
- No way to tell battery charge state. It just turns on without any notion about battery, is it full, empty or anything. That is a big problem for the outdoors use.
- Mic is very sensitive about where your mouth is. On other radios you must talk directly into the mic hole too, but on this one you'd better touch the radio with your nose.
- 30 channels with no way to reprogram frequencies. Only tones, wide/narrow and few other things could possibly be changed, and only from a computer. You can not have two channels with the same freq and different tones programmed.So, programming cable is a must. It is Kenwood-style, the cables from bluemax49s work fine.
The codeplug format begs to be
hackedoptimized. The Tx and Rx frequencies are in the simple BCD format, and there is no trace of encryption, CRC or any other anti-tamper measures. I did not have a chance to mess with the codeplug file, maybe someday later. -
4 hours ago, WRND440 said:
Hi All
New to both GMRS and HAM so hopefully this question makes sense. I would like to setup base stations at my house for both GMRS and HAM and would like to use a dual band 2M/70cm antenna as well as an Ed Fong GMRS J-pole antenna. Issue is, I only have space for one mast(25'). Would it be feasible to mount both antennas vertically on the mast at different heights? If so, what might be the best configuration. Also, I do not expect to be using both radios simultaneously. Thx in advance for the responses.
You can have one mast with two antennas, or you can have one antenna to cover 2m, 70cm, GMRS. If you use two radios for that (of course you will be using two radios!) you would need an antenna switch. Mburn's way is more fool-proof: each radio has it's own antenna.
Btw, the universally-loved Ed Fong's J-pole is not always the answer. Both Browning BR-6140 and Diamond X50 give me better results than Fong's on GMRS. If you already have Ed Fong antenna, nothing wrong with using it. But if not, you may look into other options. Browning is the same price, shorter, with RF choke integrated, and better quality overall.
- fillmoreranger and WRND440
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There are emergencies, and there are emergencies. "Mom, I missed the last bus" is a sort of emergency, maybe, possible. "Mom, I missed the last bus, and there are wolves around me" is another kind of emergency.
Emergency plan should take in account few things: 1) Who do you want to talk to? 2) What do you want to convey? 3) Maybe you only want to listen?The post from WRFP399 shows an example of very well thought-through communication plan. That plan states the need (talk to friends and family), assesses the equipment (mostly HTs), assesses limitations (HTs, terrain), and brings a solution (low-power solar-powered repeater in the boondocks) to achieve the goals. He does not write about it, but he sounds like he totally has time-based emergency schedule to save batteries and effort, and reserve frequencies. Basically, Radio-3-3-3 or the Wilderness Protocol implementation, adjusted to his needs. Everybody on this plan should have a quick reference card for the emergency comms, that very clearly and with no much ado shows how to turn radio on, tune to the freq, and what to do if no communications established.
So, when planning to emergency, thinks what are you trying to be prepared for. Is it local disaster (Coyote Creek flooding in San Jose in 2017)? Regional disaster (fire that destroyed town of Paradise in 2018 with 80+ people dead)? Bigger area emergency, like hurricane on East Cost? What exactly?
For local comms with friends and family GMRS would be enough, I think. Of course, everybody on the plan needs to know how to execute the plan when disaster hits.
For keeping in touch with extended family and friends that are not nearby, there is a Winlink, and that requires equipment, knowledge, big battery and Ham General license.
For listening, no license needed, just a good scanner (with P25 in my area).All tree items above require training. One must keep him/herself up to speed and current on frequencies and protocols, and keep this battery charged and ready.
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ALL TEH POWER WENT INTO ENORMOUS ZFONT SIZE, NO SPARE FDOR RADIO YO!
Seriously speaking, the power supply is likely the culprit, together with the wires and connectors. 12V should not be a problem, but rated current output very likely is a problem. The 25W TK-880 draws 8A on transmit, the 40W TK-880H draws 12A.
Essentially, what wayoverthere said.
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Oh, that's too bad. But thanks for the heads-up regarding Midland mic and TK-880. Pinout for the TK-880 mic connector (looking at the outlet on the radio, 1 will be on the right):
1 - Mic backlight
2 - 13.6V
3 - Ground
4 - PTT
5 - Mic ground
6 - Mic input
7 - Hook detection
8 - Mic data detectionLooking at the schematic, there is a fuse in the backlight circuit, but it should not have any effect on data. Need a service manual with schematics? Send me PM with your email, I'll send it to you.
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I encountered more ham repeaters that do not encode PL/DPL than repeaters that do. But it's not like I'm keeping a tally. "Usually" maybe a wrong word, "often" or "sometimes" would be better.
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4 hours ago, stockjock said:
And also those tones are required to access many repeaters, which are activated by the tone, ingest the weaker conversation on 467.whatever and rebroadcast it on 462.whatever usually without privacy tones.
In ham world repeater usually transmits without PL/DPL encoded. Ham repeaters are frequency-coordinated, most of them. You may never encounter two repeaters on the same output frequency. In GMRS repeater usually transmits with tones encoded. GMRS is only 8 channels and not frequency-coordinated, tones are necessity.
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Videos worth watching are only hosted on pornhub. For technical stuff, I read much faster than I can possibly watch.
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1 hour ago, n4gix said:
Back in the Dark Ages (long before even ARPANET!), I took COBOL, FORTRAN IV, and PERL during the same semester.
Must be PEARL, no? Before the ARPANET and in the same sentence with C... and F...-IV, let not these names be uttered after dark.
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On 8/29/2021 at 12:16 PM, n4gix said:
The only real difference is that these have Part 95e certification.
Which ones have Part 95e certification, the Radioddity or WLN? The picture on Amazon does not show any FCC ID.
PS.
Search for 2AN62-GMN1 produces nothing (id is taken from the Radioddity description page), and search for Radioddity's 2AN62 produces 46 results, neither of them is GM-N1. -
I live near dangerous Hayward fault, and the house is on one side of it, and wife's and mine offices and kids colleges are on the other side of it. We have an emergency plan, sort of, and communication plan is a part of it. And comm plan is not a biggest or most important part of our emergency preparedness.
However, since we are talking about radios. The first question to answer is who exactly you want to talk to in the emergency? And why? Or maybe you only want to listen?
I care about friends, I care somewhat less about society in general. Most I care about is my close family. In my family everybody is trained with GMRS radios (and also me and my daughter are hams), everybody knows what Radio-3-3-3 is and how it applies to our family needs. Everybody knows the main and reserve frequencies, and how to put radios on scan. How do they know and trained in all of that? Many years of camping, hiking, biking, kayaking and other outdoor activities with regular use of GMRS handhelds and mobile radios.
My preparedness status has some gaping holes in it. Biggest one is that my big battery for base station degraded, and I haven't got around to replace it yet. Our electric car can power our base station and computers for a couple of weeks. We actually lived off it for a week without stable electricity last year, during the big fires 10 miles from my house (SCU Complex in August 2020). But it's not much help if the car is on the _other_ side of the rift when "the big one" hits.
Second hole - I lost ability to listen to local police and fire with the move to P25. I currently lack P25 in my setup. I'm experimenting with RTL dongle, but that's not a solution, really.
GMRS swr meter
in General Discussion
Posted
That's exactly why SWR meter is not providing any useful info about HT antennas. Measuring SWR of HT antenna is a totally meaningless exercise.