Source: https://forums.mygmrs.com/topic/479-crossband-gmrs-repeater/
Timestamp: 2019-11-20 18:58:07
Document Index: 6165615

Matched Legal Cases: ['art 95', 'art 97', 'art 95', 'art 90', 'art 95', 'art 95', 'art 18', 'art 90']

Crossband GMRS Repeater - General Discussion - myGMRS.com Forums
Crossband GMRS Repeater
Started by Ba-AMI879 , Aug 02 2015 05:10 PM
#1 Ba-AMI879
Ba-AMI879
GMRS Callsign:Private
I'm not too familiar with the GMRS laws, but I was hoping someone could tell me if this is legal.
I want to set up a repeater for quick communications around my neighborhood. I'm going to put two Baofeng UV-5R's up as the repeater on my top floor connected with a wire. The only problem is the transmission from the output of the repeater will deafen the other one since they're both UHF. My question is, can I set the input frequency to an MURS channel (the handhelds transmitting to the repeater will only be at 2 watts) and set the output to a GMRS frequency? I thought it would be legal since I'm only transmitting MURS from my handhelds at legal power, then retransmitting on GMRS.
EDIT: The repeater would ID itself every 10 minutes as an old laptop will be put in between the connection with a sound file that has the callsign in voice followed by 10 minutes of silence on a loop. Incoming transmissions are sent to the laptop through the mic input and then it would be sent out with the headphones output.
Posted 03 August 2015 - 08:51 AM
No. No corssband / cross-service allowed in GMRS or MURS.
#3 wrodina
Posted 03 August 2015 - 09:41 AM
Technically, I believe the Baofeng radios are not type-certified for GMRS or MURS... so it would not be legal from that angle, either.
I have seen a youtube video where someone configures a similar setup on the amateur radio 2m band with two Baofeng HTs, and there was not any problem with interference (there is actually a cable available specifically to connect the headset/mic jacks of 2 HTs for this purpose). The HTs were sitting on the same table... I think at the lower power setting, interference is minimal. Could also do cross-band 2m/70cm in this setup as well.
BUT, you didn't ask about ham radio so that was a bit of a tangent.
All the rules (Part 95A) say is really you can not tie into the amateur radio service (Part 97). MURS (Part 95J) rules do specifically forbid any kind of repeating (including cross banding into another service).
However, the rules for GMRS don't actually prohibit one from tying a Part 90 service into Part 95A. As far as the technical aspect goes, one alternative would be to try some vertical separation (about 10 feet should be adequate)with the Baofengs if one did not want to go through the trouble of purchasing a duplexer.
Even at low power you will most likely blank the front end of the receive radio with both being in the same horizontal plane with 20 ft of one another.
#5 Ba-AMI879
So what you're saying is GMRS rules would allow me to do this, but MURS would not allow me to, correct?
From what I remember, that would be correct. I know linking into the commercial service is not forbidden specifically. Not sure if linking into other part 95 services is addressed in 95A. I know it is addressed in 95J (MURS).
#7 batt63
Posted 13 August 2015 - 02:02 PM
the issue for the handhelds is they are not filtered enough on the RX side to keep out the TX of the other out when that close together so you will be fighting desense.
and separation between each will be an issue all the time.
look at the id-o-matic 4 it is a basic repeater controller with a courtsey beep cwid or voice id if you buy the option board for it, very cheap to buy and build and works great for a basic controller.
If just CW, look at the comspec ID-8. When you actually factor in what your time may be worth to you, much more than a half hour build time and the ID-8 is cheaper.
ETA: After re-reading the rules, there is nothing that says an ISM (Part 18) device can't be used for creating cross banding links.
#9 jwilkers
GMRS and MURS are entirely different radio services. Any type of cross-communication would not be allowed. The Part 90 commercial services are also different radio services. No radio service can intercommunicate with another. Lisenses in one service are not recognized or legal on another one.