Capable Range

[Stylishxone767]

Im thinking of getting my GMRS license. I have a 25w duel band mobile radio and I was wondering what type of range I can expect out of it in a wooded area with mostly flat terrain (some low rolling hills). This would be with your standard magnetic mount dual band antenna. Anyone have experience with this? My friend is interested in getting his license to so we can broadcast from our base camp to hunting areas beyond a mile or two away.

 

[N5TWB]

Most of the answers regarding GMRS are here: https://www.fcc.gov/general/general-mobile-radio-service-gmrs

The radio you describe sounds like it's probably for ham radio and is probably not accepted for use in the GMRS by the FCC. Double-check and be certain. On the page above, note that base stations are limited to 5 watts ERP in most cases.

"Broadcast" is an incorrect term, "communicate" is what you seek to do. Wooded areas tend to absorb UHF frequencies so your range may be limited unless you have access to a repeater.

 

[gewecke]

Most of the answers regarding GMRS are here: https://www.fcc.gov/general/general-mobile-radio-service-gmrs

The radio you describe sounds like it's probably for ham radio and is probably not accepted for use in the GMRS by the FCC. Double-check and be certain. On the page above, note that base stations are limited to 5 watts ERP in most cases.

"Broadcast" is an incorrect term, "communicate" is what you seek to do. Wooded areas tend to absorb UHF frequencies so your range may be limited unless you have access to a repeater.

. 50 watts for base stations or repeaters... 73, n9zas

 

[TheSpaceMann]

Im thinking of getting my GMRS license. I have a 25w duel band mobile radio and I was wondering what type of range I can expect out of it in a wooded area with mostly flat terrain (some low rolling hills). This would be with your standard magnetic mount dual band antenna. Anyone have experience with this? My friend is interested in getting his license to so we can broadcast from our base camp to hunting areas beyond a mile or two away.

I have actually used 11 meters for a similar situation with fairly good results.

 

[AK9R]

This thread does not appear to be about amateur radio, so it's been moved to the GMRS/FRS forum.

 

[jwt873]

This would be with your standard magnetic mount dual band antenna.

I'm assuming this is an Amateur dual band antenna... If that's the case I don't believe it will be of any use for GMRS.

The Amateur 70 CM band ends at 450 Mhz.. The GMRS band covers 462 and 467 Mhz. The SWR would be way too high.

You might be able to shorten the antenna to work on GMRS, but tuning a dual bander would be tricky and you'd most likely lose the 2 meter capability.

 

[teufler]

In answer to your question,with open terrain, 10-12 miles with 25 watts into a mag mt. Now variables, poor swr, probably -3db. Sparse trees, about -2db, medium trees -6 db, dense trees -10db, and pine or swamp trees -25 db. 3db is half your power either a gain or a minus. As has been pointed out, vhf or cb would be better under the conditions you are asking about. That spectrum is not effected by foliage as much as the higher bands.

 

[NDRADIONUT]

30-50 mhz band would be an option too...

 

[gewecke]

30-50 mhz band would be an option too...

True but only on 5 channels at 49 mhz. Or the 6 meter band if you're a ham. :roll: 73, n9zas

 

[SCPD]

Choice of Radios-UHF/VHF.......

StylishX wrote "........from our base camp to hunting areas beyond a mile or two away...."

25 Watts on just about Any frequency should communicate that far. On my ranch we use 15 Watts on 451Mhz to communicate house -to- vehicle and/or walking persons well in excess of 5-6 miles- this is over all sorts of mountainous terrain. UHF, I think, would be an ideal choice in your situation, since the radios are inexpensive -- but more more to the point; because the antennas are short and effective at those wavelengths.

(Bye the bye, we have several UHF's, from an old E.F Johnson base station to some new BaoFeng 9500's and UV-5's--- I am particularly impressed with the 9500's- they are well made and you can find them for less than $100 if you shop carefully. All the vehicle mounted antennas are 6" quarter waves on the roofs-- these don't suffer nearly the thwacking around in trees and brush that tall gain antennas do, they work admirably, and sometimes that low angle of radiation is not what you want-)............. CF