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Thread: CM200 reference oscillator warp?

  1. #1
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    Default CM200 reference oscillator warp?

    I have a CM200 (old model) that is off frequency. The basic service manual shows to use a RLN4460 test box, a FKN8113 ELM adaptor cable, a RKN4083 program/test cable, and a RLN4008 RIB. It shows to program thru rear acc connector. All part numbers do not come up on MOL. Is all of this necessary? Is there another way to set transmit frequency? There is no soft pot read. CM manual says to use a "tuner program". I have tried Global Tuner and Entry Level Tuner with RIB and cable plugged into mic jack.


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    Frequency warp/reference oscillator alignment is pretty universal to all Motorola radios from the Spectra/Maxtrac on. All you need is a standard programming setup and a calibrated service monitor or frequency counter.

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    hell you can even do it with an SDR dongle in a pinch. Verify the freqency accuracy against something like a NOAA station, then adjust your PPM accordingly. Was able to get radios to within +/- 100 Hz that way. Not the best but it'll do if you don't have handy access to real test equipment. Just make sure you're going into a dummy load or something else that isn't going to put out 20W on random frequencies you don't have a license for.

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    Please do not ever align a radio against using a NOAA station as a reference. Those things can be more off frequency than a deaf soprano in a volunteer choir. At least get your SDR dongle reference from a more stable source like a LTE carrier, 7/800MHz P25 or NXDN Trunked carrier, WWV or something. NOAA is still running boat anchor gear around these parts...

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    Sinadder is correct, NOAA WX around here is 200-300hz off freq. Never use it as a reference.

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    Broadcast FM or TV is a little better - major TV and FM are usually 2-5 Hz accurate or so.

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    I use my CB radio as a reference

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    I align mine to HAARP.

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    Just set your oscillator to match the carrier frequency of the local ham repeater.

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    Ok I'm trolling. With that advice, you'd end up transmitting on UHF, with a VHF radio.

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    I sure do miss the days of being able to align my maxtracs to the russian woodpecker!

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