GMRS picking up HAM signals?

[Brocephus]

I went for a ride yesterday in George Washington National Forest near Harrisonburg VA. I didn’t go with a group, but there were lots of other wheelers out and about on the trails. I turned on my Midland MXT 275 to channel 16, and intermittently through out the day there was this guy repeating his call sign over and over, talking about some technical stuff about the frequency, using Morse code, and then at one point he said he’s was in Danville VA which was about 170 miles from where I was located. My limited understanding is that while HAM can transmit on GMRS frequencies, they generally don’t, and how was I picking this up from so far away? Does anyone have an explanation for this? Thanks. It was a clear day, I was on top of a mountain when this was happening.

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[Brocephus]

This is how I set the antenna up- the rack and the cap are aluminum, so I just stuck it on the steel bracket. Less than ideal, I’m still sorting out how I want to hard mount the radio and antenna.

 

[Radio Guy]

I've heard hams mistakenly using their amateur ID on GMRS but what you were heaing was probably a UHF amateur repeater nearby that was overloading your radio creating intermodulation distortion and ghost frequencies of the amateur repeater inside your radio that landed on a GMRS channel. All this would be happening inside your radio and not heard by anyone else except with a similar radio in the same area.

If this is what happened it would be a typical defect in the radio as Midlands are not high end commercial radios. Were you near a hilltop/mountain top with any big towers nearby?

 

[Brocephus]

Thank you, all of that sounds quite possible:

https://www.repeaterbook.com/repeaters/details.php?state_id=51&ID=11

This repeater is just across the valley from where I was wheeling- could it cause what I was hearing?

Is my janky antenna setup to blame any of this? Midland radios seem pretty popular, probably because of the price and they are relatively idiot proof- is there a better radio for the casual user who doesn’t want to mess around with a bunch of technical comms stuff?

 

[Radio Guy]

Thank you, all of that sounds quite possible:

https://www.repeaterbook.com/repeaters/details.php?state_id=51&ID=11

This repeater is just across the valley from where I was wheeling- could it cause what I was hearing?

Is my janky antenna setup to blame any of this? Midland radios seem pretty popular, probably because of the price and they are relatively idiot proof- is there a better radio for the casual user who doesn’t want to mess around with a bunch of technical comms stuff?

The overload problem and resulting ghost signals where they don't belong is common with radios like the Baofeng handhelds and other inexpensive radios. I don't have a Midland GMRS radio here to test but with my past experience with other Midland radios I suspect its a performance level issue in the design and not something external of the radio. A larger better antenna on the radio would exaggerate the problem as will moving closer to the radio tower with lots of high power UHF transmitters.

Commercial radios from Motorola, Harris and others as used by police, fire and public service will perform much better in high density RF environments but at the cost of complexity in programming and price. I use commercial radios whenever possible and have been able to get good used models at fairly cheap prices and I have the means to program them. Its not for everyone but it could be something for you to explore. I can point you towards very good deals that come up on eBay and I've purchased close to a dozen surplus cop radios both mobile and hand held over the past few years.

 

[sarguy1941]

You were hearing the GMRS repeater on Big Mountain. I have listened to it from outside of Danville. Appears to be hams that set it up. There is another on Elliots Knob on GMRS 17 and its like listening to the local 2M machine. Hours of ragchewing and complaining about everything. Both repeaters talk down into George Washington very well. Not to get off on another topic but GMRS is becoming the ham lite of radio world.

 

[sarguy1941]

I went for a ride yesterday in George Washington National Forest near Harrisonburg VA. I didn’t go with a group, but there were lots of other wheelers out and about on the trails.

BTW next time you go out throw me a PM. I'm about 2 hours from there but we head up to Nelson many nice weekends.

 

[Brocephus]

You were hearing the GMRS repeater on Big Mountain. I have listened to it from outside of Danville. Appears to be hams that set it up. There is another on Elliots Knob on GMRS 17 and its like listening to the local 2M machine. Hours of ragchewing and complaining about everything. Both repeaters talk down into George Washington very well. Not to get off on another topic but GMRS is becoming the ham lite of radio world.

Haha!! Mystery solved. Weird though- do they use GMRS/ham-lite to talk to locals? I thought the point of ham radio was to get the occasional thrill of talking to someone in Europe or whatever.

 

[Brocephus]

BTW next time you go out throw me a PM. I'm about 2 hours from there but we head up to Nelson many nice weekends.

Giddy up man, will do!

 

[Brocephus]

Giddy up man, will do!

In fact looking to a Potts Mtn run Easter weekend if you’re around.

 

[Brocephus]

The overload problem and resulting ghost signals where they don't belong is common with radios like the Baofeng handhelds and other inexpensive radios. I don't have a Midland GMRS radio here to test but with my past experience with other Midland radios I suspect its a performance level issue in the design and not something external of the radio. A larger better antenna on the radio would exaggerate the problem as will moving closer to the radio tower with lots of high power UHF transmitters.

Commercial radios from Motorola, Harris and others as used by police, fire and public service will perform much better in high density RF environments but at the cost of complexity in programming and price. I use commercial radios whenever possible and have been able to get good used models at fairly cheap prices and I have the means to program them. Its not for everyone but it could be something for you to explore. I can point you towards very good deals that come up on eBay and I've purchased close to a dozen surplus cop radios both mobile and hand held over the past few years.

Thanks man, you are a wealth of information. I’ve read a lot of your posts.

 

[Radio Guy]

Haha!! Mystery solved. Weird though- do they use GMRS/ham-lite to talk to locals? I thought the point of ham radio was to get the occasional thrill of talking to someone in Europe or whatever.

The fact you heard someone from 170mi away tells me it was a UHF ham repeater getting into your radio as many of them are linked together via the Internet over great distances and you heard ham callsigns. There are a handful of linked GMRS repeaters around but I would have to do some research to see if one is on your local mountain.

 

[sarguy1941]

The fact you heard someone from 170mi away tells me it was a UHF ham repeater getting into your radio as many of them are linked together via the Internet over great distances and you heard ham callsigns. There are a handful of linked GMRS repeaters around but I would have to do some research to see if one is on your local mountain.

The GMRS repeaters I mentioned are looking right over GWNF. They both have very good coverage. I can not access either on a mobile from home, but my base heard them all day long. They are definitely not balanced well but very few GMRS repeaters are.

 

[bvrballs]

HAM radio and GMRS do not share any frequencies. HAM (in the 70cm bandwidth) is in the 420 to 460 MHz range as GMAS (and FRS) are in the 470 MHz range. While FRS (a free radio service) and GMRS share some frequencies, GMRS is not a free service and requires a license. FRS is limited to 500mw of transmission power and requires a non-removable antenna. GMRS allows up to 5w of power on handheld devices and allows for removing and upgrading the antenna. Additionally, GMRS allows for repeaters. Repeaters and mobile mounted devices may transmit at up to 50w. I personally have a 45w transmitter mounted in my car. There are no FCC rules that prevent GMRS repeaters from using Morse code to identify, as is required by FCC rules on a regular basis, just like HAMs. As a HAM, I have an FCC license with a call sign. As a GMRS operator, I also have a call sign, in order to be compliant with FCC rules. They are separate and distinct. They may sound the same to people not familiar with or complying with FCC rules, but they have different formats.

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