GMRS Repeater Question

[sevansounds]

Hello all, new to the amateur radio world and have a few questions. 

 

Not too long ago I received my GMRS license to get my feet wet with amateur radio. I plan to later get my HAM license as well but want to use GMRS as more basic learning grounds. 

 

I've monitored GMRS freqs in my area (Longwood, FL) and rarely, if ever, hear any chatter. I've tied into some local HAM repeaters just to see if I'm setting up my radio correctly and have been able to hear local chatter and also hit some of the local repeaters....one question is that I assume GMRS isn't used very often?

 

I also have a general repeater question....can you "repeater skip"? I was up in the mountains in North Carolina during the fall and met a guy up on a mountain who also had his GMRS license, maybe his HAM license as well and mentioned that occasionally when up on the mountain that he can talk to his brother over repeaters who lives here in Florida! I believe he said he was doing it over GMRS frequencies but it could have been Ham freq's...I don't recall. 

 

Either way I have a friend who lives in Naples, FL which is about 200 miles from me (much shorter than the mileage the guy on top of the mountain) who has also recently gotten into amateur radio and received his GMRS license. I'm curious if him and I would be able to communicate with eachother via GMRS repeaters?? If so...how do we accomplish this? 

 

If its not possible via GMRS, is it possible (or likely) feasible via HAM frequencies like 2m or 70cm?

 

I'll start with those questions and hope for some responses to work off of. 

 

Thanks in advance for everyones time!

 

Shaun

WQWT707 in Longwood, FL

[jmoylan69]

The long and short is yes UHF can travel hundreds of miles with clear line of sight.  Satellite Communication for example most often operate in U/V mode. meaning that pending what country made the satellite it will transmit in UHF mode and Receive in VHF mode.  they typically are less than a full watt of power, something between the order of .2 watts to .8 watts. you can listen to satellites like SA-50 on a Baofeng handheld with the squelch open. now if you have an Arrow U/V weak signal antenna you can really get out. 

 

 

As far as "repeater Skipping", i've never even heard of that. im not sure what you mean by it. The theory id have is if he has a 25 or 50 watt mobile and you are high enough or the repeater is high enough and far enough out, you could transmit 80 plus miles away to "that" repeaters freq's for that local area and then that person would do the same.  Im not sure what you mean by "repeater SKIP". out here in nevada i can take a juentai 6188 with a jpole and transmit to ELKO NV over a mountain range to the repeater in ELKO on UHF. I don't hear the repeater keying up, but the hams there can hear me and they Transmit to my repeater out here via tone patch to a VHF repeater. radio waves travel farther than you think.  and UHF and VHF  pass through the ionosphere which is why you can use a radio like a baofeng for Satellite Communications.

 

As far as nothing on GMRS goes, that could simply be no one on the air or not used to much in your area. or something else to remember, you are a licensed GMRS USER NOW, you are allowed to operate to 50 watts. most folks do not have licenses and buy the bubble pack radios that are 1/2watt with a ridiculous rubber duck that probably wont do a mile. something to think about.    Everything comes down to ANTENNA's with radios more than power. i've talked some 30 miles away to reach a repeater on my UV5R with a NA-771 anteanna on LOW POWER simply standing in a position the signal could pass between. just remember your signal cant be blocked. if i took my UV5R to a city i bet i'd probably not get a mile. with all the stuff in the way to block it. ALSO the radios you buy in walmart etc will not allow repeater connection!! so there could be a ton of people using bubble pack radios and you'd never hear them unless they were very close by.

 

I use the satellite commo as an example of how far a 1 watt radio signal will travel. Most satellites are 150 to 400 miles up and you can reach them  with a handheld and the sat's  have a max 1 watt receive limit!  most of them. so dont think your radio "whatever it is" wont do it. just think antenna!!

[zap]

The long and short is yes UHF can travel hundreds of miles with clear line of sight. Satellite Communication for example most often operate in U/V mode. meaning that pending what country made the satellite it will transmit in UHF mode and Receive in VHF mode. they typically are less than a full watt of power, something between the order of .2 watts to .8 watts. you can listen to satellites like SA-50 on a Baofeng handheld with the squelch open. now if you have an Arrow U/V weak signal antenna you can really get out.

 

 

As far as "repeater Skipping", i've never even heard of that. im not sure what you mean by it. The theory id have is if he has a 25 or 50 watt mobile and you are high enough or the repeater is high enough and far enough out, you could transmit 80 plus miles away to "that" repeaters freq's for that local area and then that person would do the same. Im not sure what you mean by "repeater SKIP". out here in nevada i can take a juentai 6188 with a jpole and transmit to ELKO NV over a mountain range to the repeater in ELKO on UHF. I don't hear the repeater keying up, but the hams there can hear me and they Transmit to my repeater out here via tone patch to a VHF repeater. radio waves travel farther than you think. and UHF and VHF pass through the ionosphere which is why you can use a radio like a baofeng for Satellite Communications.

 

As far as nothing on GMRS goes, that could simply be no one on the air or not used to much in your area. or something else to remember, you are a licensed GMRS USER NOW, you are allowed to operate to 50 watts. most folks do not have licenses and buy the bubble pack radios that are 1/2watt with a ridiculous rubber duck that probably wont do a mile. something to think about. Everything comes down to ANTENNA's with radios more than power. i've talked some 30 miles away to reach a repeater on my UV5R with a NA-771 anteanna on LOW POWER simply standing in a position the signal could pass between. just remember your signal cant be blocked. if i took my UV5R to a city i bet i'd probably not get a mile. with all the stuff in the way to block it. ALSO the radios you buy in walmart etc will not allow repeater connection!! so there could be a ton of people using bubble pack radios and you'd never hear them unless they were very close by.

 

I use the satellite commo as an example of how far a 1 watt radio signal will travel. Most satellites are 150 to 400 miles up and you can reach them with a handheld and the sat's have a max 1 watt receive limit! most of them. so dont think your radio "whatever it is" wont do it. just think antenna!!

NASA sent video 250,000 miles from the moon using 3W of RF.

 

Line of sight is the biggest thing about UHF. If the OP's friend had LOS to the repeater, 80-150 miles from a handheld is perfectly capable.

 

Also, it would surprise most to know that the radios used in aircraft are generally 10W (AM) radios. Though transmitting in the lower portion of the VHF high band it is still based on LOS communication principles.

 

 

Sent from my iPhone using Tapatalk

[jmoylan69]

yep very true, i was not aware though that it was a 3w Radio... fascinating stuff. 

 

but yep i get out very well on my HT for what i do. and im able to hit the repeaters both distant and close by. the closest one is only 9 miles away i think. but the others are a good 50 plus. and true on the aircraft radios. being a pilot myself i know they're not that strong but because of altitude can get out with ease.. its all antenna and altitude.

[ASRM]

We had some ducting on our repeater were about 100 miles away a user was hitting our repeater at full quieting with a 10 watt mobile on a mag mount 1/4 wave on top a fridge. It was super clear for about half an hour, so in a way you are seeing skip, but not like you would on 10-11 or the other HF frequencies.

 

Something to keep in mind is just cause you hear a repeater on GMRS doesn't mean you have access. You should acquire permission, lately on ours, since it reaches 30-40 miles on mobile in every direction we have had some people coming on and wanting to talk. We use digital tone squelch and you would have to be trying the various tones to gain access. To me that is pirating and not using a travel tone (which we don't do).

[sevansounds]

Hey guys, Thanks for all of the responses. Some good info for sure to be learned. 

 

I currently have a Baofeng UV5R and a Yaseu VX8, both using aftermarket antennas. I've been doing a lot of reading just to understand the RF world better but there is still plenty to read and learn. 

 

In regards to my initial curiosities. The gentlemen I was talking about up on the mountain was also using a Baofeng UV5R. Our elevation was around 5000 but what really blew my mind was that he said he can make contact with his brother who lives all the way in Florida. Now I understand with a decent path to a repeater you can really reach out and get some distances (when I camp up at those elevations I can hear all kinds of chatter all over the place from pretty decent distances) but how in the heck is he able to, through the use of a repeater, reach his brother who is all the way in Florida?? Were talking roughly 500 miles from where he and I were standing in North Carolina to where he said his brother lives. Now at the time I should have been more inquisitive to ask how he was doing it but that now brings me to this forum to learn how he may have. 

 

I mentioned "repeater skipping" as a term I just pulled out of a hat, i've never heard of it but I wondered if that was how he was accomplishing those distances. Transmit to one repeater say 20 ish miles away, that repeater transmits to another, and to another and so on till you reach a destination but I'm sure its a pretty bogus idea. 

 

So with that being said. Lets say I'm on top of a mountain in North Carolina using a 5 watt HT and I want to make a connection with my dad who lives in Florida who, for the sake of conversation is on a mobile or base unit). What kind of power/setup/connectivity would be needed for us to be able to transmit and receive to eachother? 

[zap]

Path loss for 500 miles is roughly 144 dB. A UHF HT transmits at 36 dBm. That's a received signal strength of -108 dBm. That gives roughly 10 dB left in link budget to adjust for non-perfect HT antennas.

 

Most likely, either a repeater somewhere was in use or a linked system. As far as the physics go, it could be done with a clear line of sight on simplex.

 

 

Sent from my iPhone using Tapatalk

[WQPE714]

We had some ducting on our repeater were about 100 miles away a user was hitting our repeater at full quieting with a 10 watt mobile on a mag mount 1/4 wave on top a fridge. It was super clear for about half an hour, so in a way you are seeing skip, but not like you would on 10-11 or the other HF frequencies.

 

Something to keep in mind is just cause you hear a repeater on GMRS doesn't mean you have access. You should acquire permission, lately on ours, since it reaches 30-40 miles on mobile in every direction we have had some people coming on and wanting to talk. We use digital tone squelch and you would have to be trying the various tones to gain access. To me that is pirating and not using a travel tone (which we don't do).

 

You would just have to listen on a cheap $10dollar RTL SDR or most scanners to get the tone instantly actually. My scanner can also get the P25 NACs.