I cant seem to get the quote function to work.. so here is a cut/paste

Two questions:
First: If you have a GMRS license, is there any reason you can't legally transmit on the GMRS frequencies with a ham transceiver? Outside of an emergency, that is.

Second: The same question for FRS frequencies. If you limit your power to the 1/2 watt required by FRS rules, can you also transmit on FRS frequencies?

my response


The short answer is that it is illegal to transmit using amateur radios on any frequency not allocated to the amateur service unless it is in response to a real and present danger to life or property. Even then, be prepared to receive a major hassle from the agency that is allocated to that frequency such as police, medical etc.

The long answer.
Radio frequencies are allocated by the federal government by two agencies. The FCC (Federal Communications Commission) allocates all non-governmental frequencies. NTIA (National Telecommunications & Information Administration) assigns governmental frequencies.

So if you transmit “out of allocation” the response you will get depends on whose turf you trespass.

But in response to your question being limited to FRS/GMRS frequencies, these are structured and allocated by the FCC. They have established criteria for each of several categories as listed in the Federal Code of Regulations (CFR).

Part 87 Aviation Services
Part 90 Private Land Mobile Radio Services
Part 95 Personal Radio Services (includes GMRS, FRS, CB, & M U R S)
Part 97 Amateur Radio Service

Each of these parts define (among other things) the technical standards that equipment used in each service must conform to. Specifically, amateur radios (CFR part 97) do not meet the requirements of any other CFR Part.

It is not just a matter of configuring an amateur radio to the same configuration as say a CFR Part 95 (GMRS, MURS etc.). Radios used in each service (except amateur) have to meet their individual CFR Part specifications and be submitted to the FCC or a specific authorization.

If you look at a business band radio you will see a type acceptance number which is issued to the manufacturer for a particular model of a specific radio. Each model must be individually submitted to the FCC for type acceptance. Which is one of the reasons commercial radios cost so much more than amateur radios.

Amateur radios (in the US) do not have to meet any specific criteria.

Of course it is possible to modify many amateur radios to operate outside of the amateur allocations. However they usually do not perform well outside their design criteria.

Most amateur radios have filters to limit the reception out of allocation. This is needed, especially in urban areas to reduce interference from other services. So although the modified radio may transmit outside its allocation, it probably will receive very poorly.

A case in point. I was working with a group of archaeologists in a remote part of the Arizona desert. Many were using FRS radios. I have a GMRS license. One of the specifications of GMRS is that a licensee can use a more powerful GMRS radio (under certain circumstances) on the FRS frequencies. They both are in the same CFR Part 95. I have a GMRS Part 95 authorized radio. It was configured at 5 watts with a short rubber antenna. No problem working folks 7 miles away.

I needed to leave the radio for a few minutes so I put my amateur radio on the GMRS/FRS frequency. It was attached to a 6' tall amateur antenna on a 20 foot mast. I missed several calls using that radio that I clearly heard on the GMRS/FRS radio. That incident prompted me to run several tests on the receiver of my amateur radio. It was much less sensitive outside of the amateur bands.

I have some rather sophisticated radio test equipment. It is easy for me to see which transmitters are amateur and which are the various other allocations. Frequency stability and precision, modulation characteristics and other “fingerprints” provide easy identification.

/blabber mode off/

Nomad