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Fairbanks Morse Model 8a Problem
#9

(01-20-2016, 10:19 AM)bm071 Wrote:  ......I counted all the resistors in the chassis then compared to the schematic and come up 4 short...so far I cannot find 3of the 4.... #59 the 2.2.meg, #22 - 1000ohm and #23 - 15,000ohm.   I cannot see where they may have once been in the circuit is the other problem. The caps are #8,9,38 (I think). 

If those resistors were back in the circuit would that fix my problem or does their placement not affect the low bias, high b+?.......

It depends on exactly which caps and resistors are missing if they might be causing your problem.

I once had a Zenith chassis that had been hacked on and I had to retrace everything to make sure parts were where they should be.  I made a copy of the schematic and used colored pencils to slowly trace things out, correcting problems as I went.  It can be slow and tedious, but you need to find what is missing and try to correct it before doing much more troubleshooting.

John KK4ZLF
Lexington, KY
"illegitimis non carborundum"


Messages In This Thread
Fairbanks Morse Model 8a Problem - by bm071 - 01-15-2016, 10:23 AM
RE: Fairbanks Morse Model 8a Problem - by bm071 - 01-18-2016, 10:24 AM
RE: Fairbanks Morse Model 8a Problem - by bm071 - 01-18-2016, 10:40 AM
RE: Fairbanks Morse Model 8a Problem - by bm071 - 01-18-2016, 08:37 PM
RE: Fairbanks Morse Model 8a Problem - by bm071 - 01-20-2016, 10:19 AM
RE: Fairbanks Morse Model 8a Problem - by Eliot Ness - 01-20-2016, 05:34 PM
RE: Fairbanks Morse Model 8a Problem - by bm071 - 01-20-2016, 06:55 PM
RE: Fairbanks Morse Model 8a Problem - by bm071 - 01-20-2016, 06:59 PM



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