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Fairbanks Morse Model 8a Problem
#6

Please dis-regard my last post....I double checked voltage going to the rf coil and the osc. coil. I do have voltage going to the rf coil at all times. 300v. Checked continuity on all terminals of both the rf coil and the osc. coils appears fine. The osc coil has
 -54v.   
 From what I can tell by looking at the band switch, the 6k7(left side of schematic by the coils) only gets plate voltage on the two short wave bands. Pin 4 always has voltage(my mistake dirty terminals first check) 125v with no plate voltage, 154v with plate voltage. Looking at the chassis the only two things I visually see connecting the antenna coil to the rest of the circut is ground and the 47000 ohm resistor.(#16 on schematic if I'm reading it correctly...no voltage detected.)

   

I checked continuity on both of the if coils(ones with trimmers) and they check good. Have voltage on red and blue wires, none on the blacks.  

The other 6k7(if tube?) has voltage all the time plate and pin 4(300 & 154v)..

bm




Messages In This Thread
Fairbanks Morse Model 8a Problem - by bm071 - 01-15-2016, 09:23 AM
RE: Fairbanks Morse Model 8a Problem - by bm071 - 01-18-2016, 09:24 AM
RE: Fairbanks Morse Model 8a Problem - by bm071 - 01-18-2016, 09:40 AM
RE: Fairbanks Morse Model 8a Problem - by bm071 - 01-18-2016, 07:37 PM
RE: Fairbanks Morse Model 8a Problem - by bm071 - 01-20-2016, 09:19 AM
RE: Fairbanks Morse Model 8a Problem - by bm071 - 01-20-2016, 05:55 PM
RE: Fairbanks Morse Model 8a Problem - by bm071 - 01-20-2016, 05:59 PM



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