GMRS 2 way radios

[Skennenden]

Well, I just ordered the Midland GXT800VP4 model. Is it possible to try a GMRS channel real quickly just to see if it's any better before paying for the license? We would just test it out in the woods around our house to make sure that it was really better. What do you think? I fully intend to get the license right away.

 

[Whiteman]

Testing GMRS!??

While I would never encourage the illegal use of regulated FCC frequencies, and I am sure the regulations of the use of GMRS radios at power over .5 watts are observed by every single user, I suspect that you could probably sneak a little QSO (two way conversation) without the FCC police fetching you from the top of Mt. Lafayette in their attack helicopters.

I'll venture further in my speculation: Millions of these radios are being sold, and almost as many are being used without regard for the licensing requirements. The FCC's response: . I may be wrong, but I don't think the U.S. Attorneys have this one on their radar screens.

But it would be wrong. Stick to 65 mph on Route 93. Don't take the tags off of your mattress.

 

[Skennenden]

Thanks. I'll try them out first and if the GMRS has better range, then I'll get the license.

 

[Skennenden]

Ok, here I go again. We purchased the Midland GXT800 GMRS radios because all of the reviews said that they were one of the best. We've tried them out using a GMRS channel and don't find that the range is any better than our old Motorola 5200 FRS radios. We expected them to be somewhat better at least. Why is that? Are we doing something wrong? Any advice would really be appreciated.

 

[DougPaul]

Ok, here I go again. We purchased the Midland GXT800 GMRS radios because all of the reviews said that they were one of the best. We've tried them out using a GMRS channel and don't find that the range is any better than our old Motorola 5200 FRS radios. We expected them to be somewhat better at least. Why is that? Are we doing something wrong? Any advice would really be appreciated.

The notion of "best" often depends on which reviewer you choose to believe...

If you are operating at the same transmitter power levels, there will be no difference. Higher power levels may or may not make a difference, depending upon the terrain. On flat terrain, the signal will usually die off slowly with distance and additional power will generally help extend the usable distance. But if you go around behind an obstacle, it is possible the the signal will be attenuated sufficiently that far more than 5 watts will be required to make contact.

Make sure you are doing the test at a higher power level.

Doug

 

[Skennenden]

They are on high setting. We figure my husband was about 3 miles away on a road walk in a rural area when we lost communication. We live on a hill and he was down on the flats. Seems that was about the same place that the Motorolas were out of range too.

 

[MichaelJ]

So you're on a GMRS-specific channel (0-6 or above 14) and on the high power (5w) setting?

Next question is did you both lose contact with each other or could one hear the other but not vice/versa? I've had that problem, where I was up on a peak at a ski area and una_dogger at the base, and I could hear her crystal-clear, but she couldn't hear my responses. No explanation.

From hill to flats ... if the hill is concave, and there's no line-of-sight at all from the road to the house, there may not be any radio at all that will work without being able to bounce the signal.

 

[Skennenden]

Yes, they were on channel 20 on high setting. I could hear his alert signal trying to reach me and some voice, but he couldn't hear me at all, not even my alert signal. When we testing our Motorola 5200 talk abouts they seemed to have better range on the same route. Strange to me because they are only FRS and have a lower power level.

 

[MichaelJ]

Digital squelch, continuous tone squelch, or just open channel?

 

[Skennenden]

I have it set on digital.

 

[MichaelJ]

I have a gut feeling (no scientific evidence for this) that digital squelch dies out sooner with poor reception. The reason I think this is the same way that you could still hear an analog cell phone with lousy service, but the digital would fall over if the important bits didn't make it over the air.

Give continuous tone or no squelch at all a try, I'm curious to have real evidence if it makes a difference or not...

 

[kmorgan]

If you want range, a good method might be to get a Ham license* and use repeaters where available. (There are about 5 2M repeaters around the Whites. Don't know about coverage in the DAKS.) Typical 2M HTs (HT=hand-held transceiver) run up to 5 watts and can use better antennas than FRS.

Doug
WB2QJE

I don't know why I hadn't done this sooner. Guess I thought the rules were still the same as when I had my novice license back in 1975! (WN2SAP) I picked up the Technician study guide 3 weeks ago and took (and aced) the test this last Sunday. Just waiting for my call to show up on the FCC database.

I wonder how many hikers are Hams.

Kevin

 

[Skennenden]

I'll try no squelch the next time we test them. If it makes a difference I'll let you know. Thanks for your advice.

 

[DougPaul]

I'll try no squelch the next time we test them. If it makes a difference I'll let you know. Thanks for your advice.

Squelch only quiets the receiver when there is no (strong enough) incoming signal. Once the receiver is open, it has no effect on the apparent signal strength.

Tone/digital squelches wait for a specific tone/digital sequence before opening the receiver. There is no need to use them unless one becomes annoyed by hearing other users of the same channel.

Doug

 

[MichaelJ]

And my theory is that at the fringes of range, the digital codes don't come across clearly enough to open the receiver, just as how a digital cell phone or television just falls apart when an older analog unit could still be usable albeit behind snow and static.

 

[DougPaul]

And my theory is that at the fringes of range, the digital codes don't come across clearly enough to open the receiver, just as how a digital cell phone or television just falls apart when an older analog unit could still be usable albeit behind snow and static.

The comparison between analog/digital phone/TV cannot be carried over to a squelch--the squelch need only transmit a few bits in a reasonable amount of time--phones and TVs need to maintain fairly high bit rates. A counter example: the GPS signal (a digital signal) is well below the noise level to an analog receiver, but well above the noise level after the appropriate digital signal processing.

However, the squelch is only the squelch. Once you have the signal, you can listen to the signal-to-noise ratio. FRS/GMRS radios have a button to open the receiver and thus you can completely remove the squelch from the measurement.G

Doug