The other day going thru some old box’s on the shelf I ran across the proof of the annual transmitter testing certification sticker for one of my old Civil Air Patrol < CAP > radios. I seem to remember that I had to get them bench test annual to ensure they were within the frequency tolerance.
I look at the part 95 rules, and came across these:
§95.603 Certification required.
Each GMRS transmitter (a transmitter that operates or is intended to operate at a station authorized in the GMRS) must be certificated.
§95.621 GMRS transmitter channel frequencies.
(a) The GMRS transmitter channel frequencies (reference frequencies from which the carrier frequency, suppressed or otherwise, may not deviate by more than the specified frequency tolerance) are 462.5500, 462.5625, 462.5750, 462.5875, 462.6000, 462.6125, 462.6250, 462.6375, 462.6500, 462.6625, 462.6750, 462.6875, 462.7000, 462.7125, 462.7250, 467.5500, 467.5750, 467.6000, 467.6250, 467.6500, 467.6750, 467.7000, and 467.7250.
Note: Certain GMRS transmitter channel frequencies are authorized only for certain station classes and station locations. See part 95, subpart A.
(b.) Each GMRS transmitter for mobile station, small base station and control station operation must be maintained within a frequency tolerance of 0.0005%. Each GMRS transmitter for base station (except small base), mobile relay station or fixed station operation must be maintained within a frequency tolerance of 0.00025%.
I am not seeing how often this need to be done? Does anyone have any ideas?