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Need Manuals & Schematics for Belar FMM-1/FMS-1 Mod Monitors

R

RadioMan203

I just picked up a Belar FMM-1 & FMS-1 for the high school radio station I'm helping build and I need to get some tech data, schematics, etc for these guys. I checked the Belar web site and they only have documents available for the newer FMM-2/FMS-2.

I'm hoping I can recap and rehab most of it myself and crossing my fingers I can retune it in the field without having to send it back to Belar. If you can help me out please let me know.
 
If you have or can borrow an accurate frequency counter and generator, you can calibrate it as accurately as the counter. Use Bessel nulls for the mod function, and the coiunter to set center frequency. Since the nulls are a function of frequency, you mod accuracy will be the same as the counter - less whatever drift the box has. It has very little.
Maybe someone has a book - I seem to remember the crystal oscillator is 600KHz off carrier, but I may be out of line with that.
 
rew: I don't think you read my post. I did check the Belar site, and all they have were the FMM-2/FMS-2. I need docs for the earlier FMM-1/FMS-1 units. Believe me, I wouldn't ask if I could have found them that easily.

littlejohn: thanks for the tip. The problem is these units are of questionable vintage and I'd like to replace parts like caps, etc without having to guess at parts values. It will also be easier to troubleshoot with factory docs instead of having to waste time drawing out things by hand. I'm going to have to send the RF amp back for retuning and a self-oscillation issue, I was hoping that I could refurb the rest of the gear in-house.
 
AND...I mistakenly deleted your reply...I have manual ready to go...pls resend address...sorry...JBI
 
And thanks to you and other members of this board I'll be able to use the monitors to teach my students about analog FM modulation and other aspects of broadcasting thanks to the soon to be completed campus radio stations.
 
Bill: I got my FMM-1 and FMM-2 crossed up. I guess I should have read your post a little closer.
I had just downloaded a copy of the FMM-2 when I saw your post.
 
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