[ARC5] Working on the FA-7989 / TRX-102

[sbjohnston at aol.com]

I've been working on the FAA FA-8979 (aka model TRX-102) VHF AM transceiver I bought at Fair Radio a few weeks ago.   Fair Radio was kind enough to send me the manual that I forgot to pick up when I was there.  

I spent a lot of time trying to understand why the internal DC voltage buss was jumping around - when I temporarily connected a SLA battery as designed it settled right down.  Seemed like it should have been OK without a battery, when running on AC, but I guess not.

The 21.4 MHz IF, demodulator, and audio seem OK with an AM signal injected from my service monitor, but the front end does not act right.  It could be my substitute signal for the local oscillator isn't correct - I don't have any crystals.

Anyone have a receive crystal from an FA-7989/TRX-102 that I could borrow for testing?  In my extensive collection I am not finding one piece of quartz in that range!

I wish I understood why I am working so hard on this piece of equipment.  I don't even really enjoy monitoring air comms.  I think it is the high-quality construction and rugged design that get me.  



Steve WD8DAS
sbjohnston at aol.comhttp://www.wd8das.net/http://af4k-crystals.com/--------------------------------------------------------------------Radio is your best entertainment value.--------------------------------------------------------------------


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