[MRCA] AN/GRC-106 Issues

[Chris Dawkins]

When I got my 106 running the first time, someone had not put the gear train for the tuning deck together correctly. If you ran it all the way down ( or up I don't remember) the gear would jump off and you'd have to pull the amp and reset the gear train. This also caused the numbers to no quite match the tuning card.
The answer for me was to loosen the face of the amp and pull out tuning motors. Clean and line everything back up so it was centered and the small tuning gear could not fall off from running to the scale end.
That put the displayed numbers very close to the card.
Sorry I'd have to look in the manual for the correct name and number of those parts as I'm writing this from memory.

On October 26, 2016, at 11:22 AM, Ray Fantini <RAFANTINI at salisbury.edu> wrote:

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I have a AN/GRC-106 that I am working on that suffered from the usual 106 ailments, stuck DC motors and the like but think that’s all resolved now but have a new issue. The amplifier appears has issues in trying to resolve tuning and load settings on the high frequencies and I can arrive at tuning solutions for low frequencies like 3.5 and 5.0 MHz but cannot get a good tuning solution on anything above 10 MHz this is all into a 50 Ohm load and not anything with the whip antenna. Both DC motors are working and making the appropriate selections in the antenna tuning deck but when I got this radio to look at I was told that it had a bad vacuum variable (C26) but would tend to think that would be the opposite and not work at the low frequencies and work on the high but that’s not the case. Anyone else had any experience with the failure of that capacitor? The other thing I have to do when I get time to get back to working on this is check the mechanical alignment of the tune and load controls being they may be off because any of the tuning solutions I have been able to get to work do not match the published data, or is that also a sign of capacitor failure?

 

Ray F/KA3EKH
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