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Logan5

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  1. Like
    Logan5 reacted to n4gix in New GMRS Rookie in Toledo   
    Nice job on the repurposing of the old satellite antenna mount. Keeping the power as low as needed is a good thing. There's no point in simply being a "Gator Mouth" with "Cricket Ears" after all...
     
    Here is a picture of my roof's antenna farm. The far left is the repeater, the center is my 2m/70cm ham, the two on the chimney mounts are my backup antennas for 2m/70cm and 70cm ham and GMRS. My J-Pole is not visible in this photo:

  2. Like
    Logan5 reacted to brettstoner in New GMRS Rookie in Toledo   
    Thanks for the words of encouragement. Honestly it wasn't too difficult. I purchased a used TKR-820 from Tim at http://www.thetkrguy.com (which by the way fantastic job, highly recommend). It arrived at my door tuned and ready to plug in and go. Two sets of tones. 141.3 for the public and a private set for my family. I then bought a J-pole and ferrite beads from Michael at http://www.jpole-antenna.com (again also did a great job answering my questions). Purchased 50 feet of Heliax 1/2 hardline and connectors. I use to have a 900 MHz Yagi antenna for a cell phone repeater which I took down off the old Dish satellite mount. I had 1.5 PVC extending it 5ft and #4 copper running to ground. Mounted the J-Pole, weatherseal the connector, and run the Heliax down the roof and wall and into the basement. Hard part was worrying about not falling off the roof due to the snow and ice. Very slippery. I still have the LMR-400 from the old Yagi I need to take down once the weather warms up. I then went out 2 miles and adjusted the repeater output until it was loud enough to match my handheld. 
     
    I finally got a chance this afternoon to do some testing and sound quality was great. I had two goal locations, one at 1.5 miles and one at 2 miles, and both come through very clear on 5w handhelds while indoors at both locations. I see no need to upgrade antennas or get higher for more range at this time. I am happy with the performance. This is a setup for family at 3 houses.   
     
    I never realized how much height played a role. I was smart enough to realize the bubble pack claims are ridiculous but in an urban residential city I was only getting a mile with my 5w handhelds. Even now with my repeater on my roof I am only getting a little over two miles. And this is all very flat land with zero elevation change. 
     
       
  3. Like
    Logan5 reacted to n4gix in New GMRS Rookie in Toledo   
    Honestly, no. Although it would be a bit taller, that's not enough of a difference to extend your range much. The increase in "gain" only translates to effective radiated power (ERP), not distance.
     
    UHF frequencies are effectively "line of sight" with not much if any leakage beyond the horizon, which is not surprisingly known as the "radio horizon".
     
    Here is a link to a 'line-of-sight' calculator: http://www.calculatoredge.com/electronics/lineofsight.htm
     
    Enter your repeater's antenna height in the first box and assume about 5' height for an HT or mobile radio. You will be surprised at the actual correlation between height of the transmitter antenna and effective range!. These are results for the effective radio horizon for different antenna heights.
     
    30'/5' = 11 miles.
    60'/5' = 14 miles
    120'/5' = 18 miles
    240'/5' = 25 miles
    480'/5' = 34 miles
     
    Notice that the increase in height of the antenna isn't directly proportional to the effective distance. Doubling the height from 30' to 60' is only a 3 mile increase. It's a case of diminishing returns, especially when comparing the massive increase in the costs of that height!
  4. Like
    Logan5 reacted to n4gix in Travel Tones, PL/DPL differences   
    Back around 1980 one of the repeaters my shop owned was an antique (circa 1950) VHF RCA. It used a pair of 3-500Z tubes in the final amp. Those had to be replaced in pairs even if only one failed for any reason. At the time it cost around $300 for a pair of them. As of today, they are around $220 each. That repeater I programmed with a six second hang time.
  5. Like
    Logan5 reacted to mcallahan in New GMRS Rookie in Toledo   
    I'm curious as to why you chose the Nagoya NA-701C antenna to use on the GMRS-V1?  That antenna is a dual band VHF/UHF antenna, and I can't imagine it would perform as well as a UHF specific antenna.  The stock antenna on the GMRS-V1 I have found to be very excellent.
  6. Like
    Logan5 got a reaction from Hans in Travel Tones, PL/DPL differences   
    I might add, a long hang time makes it easier for even a novice repeater jammer to find your tone. We have had some illegal commercial use and used this as well as other means to investigate who it was. However we have not encountered any malicious Jamming.
  7. Like
    Logan5 reacted to mcallahan in Travel Tones, PL/DPL differences   
    In that case you may want to use "split tones."  This is means the that TX and RX tones are different - for example TX on 467.675 MHz with DCS tone 654 and RX on 462.675 with DCS tone 172.  Our club repeater uses this strategy to help limit interference.  There is even a repeater in my area that uses a digital tone for TX and an analog tone for RX.  The caveat here is that many radios are not capable of operating with split tones - the recent Midland GMRS offerings are not capable of using split tones as far as I know.  A split tone strategy can help limit interference and people inadvertently keying up your repeater, but this is not a silver bullet.  A persistent repeater jammer can easily thwart this strategy.
  8. Like
    Logan5 reacted to rabshire in Travel Tones, PL/DPL differences   
    Ok, so from what I understand, some Repeaters allow Multiple TX and RX tones. That explains why I was not allowed to use the 141.3 and was given another Private PL Tone to use on the same repeater and frequency near me.  At first, I thought they had two repeaters setup using the same frequency with separate the PL tones. That didn't seem feasible or cost effective.
     
    I'm in the process of setting up my own repeater and have to choose a Frequency and PL tones myself and thinking about a strategy to avoid not only interference but I want to make it the most private.
  9. Like
    Logan5 reacted to coryb27 in Duplexer   
    Used duplexes can be found on eBay, If you want a decent system with good receiver sensitivity stay away from the mobile style flat packs and look for a good pass / reject.  
  10. Like
    Logan5 reacted to mainehazmt in Tram 1491 weatherproofing   
    I have something very similar to that I had forgotten about thanks for the reminder.. I’m more concerned about where they connect together and it being a fine thread thus the anti seize (the nasty silver stuff that gets over everything that is great for a prank underside of car door handle) lol
  11. Like
    Logan5 reacted to mcallahan in News from NASA   
    http://replygif.net/i/1409.gif
  12. Like
    Logan5 reacted to mcallahan in MyGMRS Members Museum   
    Not "old" old, but here's a weird scanner from the 90s I still have laying around - a Sony Wavehawk ICF-SC1 which I bought around 1999 or 2000.  I remember not being able to afford the PC-programmable version of this radio, but it was my first 800 MHz scanner (upgraded from a Radio Shack Pro-71) and I could finally listen to the local county sheriff at the time.  I also remember performing a mod that I read about on a Yahoo Groups forum which would open the frequency range up to 200 KHz - 1300 MHz which was really awesome. 
     

  13. Like
    Logan5 reacted to Hans in my family and my gmrs   
    Soon enough the first or second set of batteries are burned through and then the Christmas gift bubble pack radios end up in a drawer; forgotten. Every year around the holidays there is this increase in FRS traffic which tapers off in about the time it takes to deplete a set of batteries or so.
     
    I have to chuckle though as I listen to a couple of future long term radio operators pop up on the scanner in our neighborhood. They are really working at proper technique with those little bubble packs. Be it at play or figuring out what they are going to do after school, they consistently play proper radio. This has been going on since July. I smile as it reminds me of when I was a small child and was fascinated by RF. They are truly dedicated to proper use.
  14. Like
    Logan5 reacted to Edward725 in my family and my gmrs   
    My family recently purchased a pair of Midland GXT1050 walkie-talkies and a Midland MXT115 mobile radio which we're using as a base station.  I then got a GMRS license and signed up for this forum.
     
    The post above from PastorGary has been extremely helpful as an example of how to use a callsign together with unit numbers.  My son and I are now following these examples to stay in touch during little excursions around the neighborhood.  We are using the suggested formulas of "<callsign>, Unit 1 to Unit 2" to initiate communications, and "<callsign>, system clear" when we're finished.  Thanks, PastorGary!
     
    In our neighborhood, there is little activity on the GMRS-only channels 15 through 22.  We are using channel 15 (462.550) and there is very little interference.  Channel 16 (462.575) has something in morse code a couple times a day, which sounds like some kind of automated station identification or something.  We may try to decode it someday, if we learn morse code well enough .
     
    In the meantime, we are staying away from the GMRS-FRS shared channels 1 through 7.  I think someone in the neighborhood got new walkie-talkies for Christmas, and was trying them out on GMRS-FRS shared channel 1 (462.5625).  My son (who has now gotten very interested in GMRS and is trying to learn morse code) has gotten concerned that the FCC might come after these neighbors (whoever they are) because they apparently are unlicensed and don't have a callsign, and probably they don't know what GMRS is .
     
    I'm telling my son not to worry about FCC consequences for our (unknown) neighbors.  Especially since they are using a shared FRS-GMRS channel, it seems ambiguous as to whether it is OK to use it without a license.  But just for the sake of discussion, is there any point to intervene in conversations among apparently unlicensed users (e.g., to question them about their not using a callsign), and if so, how does that differ between the shared FRS-GMRS and GMRS-only channels?
  15. Like
    Logan5 reacted to rdunajewski in mygmrs.com/links   
    Done!
  16. Like
    Logan5 reacted to mcallahan in mygmrs.com/links   
    Would be possible to get a link to my club's home page on the "Links" page?  Arizona GMRS Repeater Club: https://www.gmrs1900.net/.  We have a banner as well.
     
     
    Thanks!
     
    Matt - AGRC
     
  17. Like
    Logan5 reacted to mcallahan in Etiquette for communication using GMRS   
    Also to answer you other question, here is some good info for reading about frequency tones:
    Continuous Tone-Coded Squelch System
    Digital Code Squelch (DCS)
    CTCSS and DCS Tones -- What's the difference?
     
    btw - The "travel tone" is 141.3 Hz. Here is some good info about repeaters and offsets:
    Repeaters - RadioReferecne Wiki
    Offset - RadioReference Wiki
    For GMRS, the offset is always +5 MHz. A GMRS repeater operating on 462.675 MHz will have an input frequency 5 MHz higher at 467.675 MHz (which is also listed as a GMRS frequency).  Glad you're interested in the hobby - feel free to ask any questions!
  18. Like
    Logan5 got a reaction from jmoylan69 in What steps to get a GMRS repeater online?   
    What do you have for antenna height? Obstructions? In most applications the height of antenna is most important. using a ground plane I assume a Mag mount? Although not ideal, it could get you started. Tell us more about your site.
  19. Like
    Logan5 got a reaction from satzmichael in Repeater Interference from Maritime Operations - Please Report   
    Our "Travel Tone" is again active, however we are still catching a small amount of illegal interference. If you have trouble with that tone, let me know and I will give you an alternative.
  20. Like
    Logan5 reacted to intermod in Repeater Interference from Maritime Operations - Please Report   
    I feel your pain.   The Zetron community tone panel we are using on both repeaters have a mode where it will repeat all traffic (like a carrier squelch mode).  However, if the incoming tone is one that is enabled, it will encode that on the output.  Otherwise it just uses no encode or a single encode code I set for carrier or "wrong code" traffic.   This does not impact our users as most run tone squelch, but allows me to hear all the maritime trash.  Or the unlicensed users...
     
    G    
  21. Like
    Logan5 reacted to WQYC236 in Transmitting from a "fixed station" on 467 main channels.   
    I think that I'm going back to two tin cans and a long string...at least I know where I stand with that communications device.  
  22. Like
    Logan5 got a reaction from leszek in Transmitting from a "fixed station" on 467 main channels.   
    indeed, I would not have a problem with a licensed user using 50 watt's into the repeater, If he was 30 to 40 miles out and such wattage was necessary for repeater access. I would also expect he turn down his power if he is inside of the standard service area and even 25 watts would be excessive. Some people just think it's all about wattage.
  23. Like
    Logan5 reacted to Jones in Transmitting from a "fixed station" on 467 main channels.   
    One thing about "Fixed Stations" that no one is taking into consideration is that they must use directional antennas.  Fixed stations are not used for talking to either one another, or mobile units directly.  A Fixed station would be used as a "remote input" device to go into a repeater.
     
    A Fixed station could be a small base station set up to talk and hear through the main repeater, not talking directly to mobile units, or it could be a similar setup to what I have in my basement on a Ham service repeater.
     
    I have what would be considered a "Fixed Station" set up on an Emergency Alert System decoder box.  When weather alerts, Amber alerts, local emergencies, etc. are decoded by the EAS, it keys up a 2 Watt transmitter, going into a 7 element Yagi antenna, that points to the UHF Ham repeater linking hub about 7 miles away from me.  This unit doesn't receive anything, it is transmit only, one channel, directly into the repeater... a "Fixed Station".
  24. Like
    Logan5 reacted to Jones in Transmitting from a "fixed station" on 467 main channels.   
    The way the FCC has this latest rule written is very poorly worded, and confusing. This is not what the original ruling meant, and I am going to contact the FCC about having the wording modified a bit to clear things up. (However, they seem to very much like muddy wording.)
     
    Let me try to make the Fixed vs. Base station thing a bit more clear for beginners on the forum....
     
    A repeater system is an un-attended automatic signal relaying device that picks up a communication on one channel, and relays it on another channel.
     
    A Fixed station is a low-powered stationary device that is used to communicate with other units in its group through the one single repeater system which it is set up for.
     
    A Base station is a high-powered station, likely using an omni-directional antenna at a high elevation, that can be used to communicate via repeaters, or directly with mobile and portable units, or other base stations.
     
    A Control station is either a fixed, base, or mobile station that has the necessary tone generators or other signalling device to control the repeater system, as in turn it on and off remotely, without having to travel to the repeater site.
     
    All of this terminology is left over from the business radio service. Typical UHF Business mobiles have 2 channels, "Main", which is through the repeater, and "Talkaround" which is simplex on the repeater's output frequency.  The business office/secretary likely has a "Fixed Station" on her desk, which is a 1 or 2 Watt radio with a small directional antenna on the roof pointed to hit the repeater.  In a typical VHF business system, all radios would be simplex, and the "Base Station" would need to have a tall tower on site to communicate with the mobiles.
  25. Like
    Logan5 reacted to leszek in Transmitting from a "fixed station" on 467 main channels.   
    50W from a mobile station is allowed on 467 when talking to a repeater.
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