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I just have a few questions...I attempted to use the search function to find the answer but I didnt find anything definitive. Anyways...I am looking to set up a GMRS system so I can communicate with my family. I am aware that repeaters in the system must be within certain tolorances to be used on GMRS, so one of my questions is what repeaters out there are GMRS legal. I also want to use a GP300 and a HT1550 on this system to access the repeater. My second question is are these radios legal for GMRS? Thank you in advance
It is my understanding that as long as you have a GMRS license it should list as to what the limits should be.
A GP300 and HT1550 radios should be legal to use on the GMRS freqs. I think you might run into trouble using the radios on the FRS freqs which are not the itinerant freqs to GMRS.
" ah the fatman made a funny!" - Stewie from the family guy.
I went to the doctor and all he did was just suck blood. Never go to Dr Acula - M. Hedberg
It is my understanding that any Part 90 type accepted radio is acceptable for use on the Part 95 GMRS service. (That seems to be the concensus from various folk here on the board). As far as I know a GP300 and a HT1550 are acceptable (presuming the GP300 can do narrowband channels).
There are 8 repeater pairs in the GMRS and 7 low/high pairs in the FRS service. The frequencies are as follows:
GMRS: (Simplex & Repeater Outputs - Repeater Inputs are +5MHz)
As you can see, the FRS pairs are the 12.5khz channels between the GMRS pairs. For purposes of interoperability between the two services, GMRS licensees may legally transmit on low power on the first 7 (low side) FRS frequencies.
To make things simple; if you can use the radio for business purposes on UHF, you can use it on GMRS.
This includes the P110/GP300, HT series, all JEDI and Sabers.
Narrowband is 6.25 Khz channel spacing, standard spacing is 12.5 Khz.
Every Saber I own will program 6.25, but not the P110/GP300s, HT series and even some of the JEDI series can't do narrow band channels due to the differences in the masked controllers not being pre-programmed to allow programmable channel spacing.
Many use GMRS for their businesses, I know several security companies that use it, and are licensed on pairs, and they mainly use GP300s for portable and 'Tracs and GM300s for mobiles.
You CANNOT use any radio but one is type accepted for FRS. A FRS radio must have a non-detachable antenna and only capable of a 500Mw power output. I am not sure about GMRS.
Licensees are allowed 5 watt output on the first 7 FRS channels.
We're laying out cash, so we get the perk of being allowed to stomp the Wal-Martians and Sammie-Mammies.
Which doesn't happen much.... Usually the GMRS folks are on FRS trying to get away from the illegal FRS folks on GMRS. It's pathetic either way and I wonder if anyone besides us check-writers really care...?
Woody_99 wrote:Which doesn't happen much.... Usually the GMRS folks are on FRS trying to get away from the illegal FRS folks on GMRS. It's pathetic either way and I wonder if anyone besides us check-writers really care...?
One thing you can do to mitigate that is use a nonstandard PL/DPL code. I have yet to see a bubblewrap radio that would do, for example, 69.3 Hz.
FRS is narrowband but so far GMRS is not. I'm sure that day will come but for GMRS use, no need to worry about the radio being narrowband capable. Like I said - yet.
Chris,
Hamming 31 years http://www.wa2zdy.com
Wesley Chapel, Pasco County, Florida
Snow? What's that?!
The human race is proof that Darwin was wrong.
It is good to know I can use those radios. Now all I need to do is figure out what repeater I can use. Does anyone have any suggestions on a repeater i can fairly easily get thats pretty cheep and is legal on GMRS?
while the common convention is that any part 90 radio is legal on GMRS. The rules DONT say that. Only specificly certified part 95 parts are legal on GMRS.
It is good to know I can use those radios. Now all I need to do is figure out what repeater I can use. Does anyone have any suggestions on a repeater i can fairly easily get thats pretty cheep and is legal on GMRS?
-Bob
The same applies for the repeaters.. You just have to watch the output wattage, but im not sure what the rules are for ERP etc. I'm sure 50 watts would be legal though. Should be easy to google some answers there for ERP gain antennas etc etc. In any case an R100 would be decent and cheap. Micor stuff can be had for free but you have to buy crystals (yuck). I have a 250 watt UHF Micor
Never actually USED it for anything though.... We are limitted to 50 watts for UHF Ham due to some radar installation down the cape or something...Public Safety and business dont have that restriction IIRC dunno about GMRS.
Will, What part 95 subsection did you see the part 90 allowment. I know its been standard that the Bureo's allowing part 90 radio's, but the last time I checked the part 95 federal registry the only referance to part 90 was a transitional warning to not cause interference when GMRS was orginally carved out of part 90 spectrum.
47 C.F.R. section 95.603(a): "Each GMRS transmitter . . . must be certificated."
47 C.F.R. section 95.605: "Any entity may request certification for its transmitter when the transmitter is used in the GMRS . . . following the procedures in Part 2 of this chapter."
The balance of Part 95, sub-part E sets forth the technical specifications for GMRS certification.
The bottom line, therefore, is that any GMRS radio should be type accepted for Part 95. Generally speaking, most manufacturers for UHF portable and low- and mid-power mobile and base station equipment seek Part 95 type acceptance at the same time as Part 90 type acceptance: the technical standards are the same and there is no additional fee. But unless the equipment has actually been type accepted, its use on GMRS does not meet the regulations:
47 C.F.R. section 95.129: "Every station in a GMRS system must use transmitters the FCC has certificated for use in the GMRS."
The FCC's Enforcement Bureau, who interput the rules as well as enforce them has 'allowed' radio transmitters that are type accepted/certificated in Part 90 and that meet ALL the technical standards in Part 95 to be used on GMRS. Also this decision by the FCC's Enforcement Bureau is also based on that no interference be caused to other radio services, especially Part 90 public safety.
Thank you for all the information! Looks like I might be able to do this LOL. Now all I need to do is find a repeater (such as a R100). Any ideas (Other than EBAY) I could find any?
In the Mitrek, "Note that if for some reason you "flip over" the RX local oscillator / multiplier (the injection chain) to the opposite side (i.e. go from low side injection to high side or vice versa) any digital information (dpl or data) will be inverted at the discriminator output. This can cause problems if the system does not have an option for inverted DPL. The table below may help.
In the Mitrek, "Note that if for some reason you "flip over" the RX local oscillator / multiplier (the injection chain) to the opposite side (i.e. go from low side injection to high side or vice versa) any digital information (dpl or data) will be inverted at the discriminator output. This can cause problems if the system does not have an option for inverted DPL. The table below may help.
Yes, I wasnt going to say anything BUT.. Every inverted DPL would have a regular match on the opposite end of the chart... The inverted option is for use with amplifiers with odd numbers of stages.. IE: Your DPL would come out of the radio and through the amplifier become inverted, so you need to invert it so keep it normal at the output. At least that's my understanding.
