Quote:
Originally Posted by Mr.Duncan
Still digging into the vertical issue. Removed the chassis, triple checked all capacitors, re-did all the solder points to be safe.
Swapped out both Vert OSC ( 6BF6) and Vert Output ( 6DT5) with some good NOS tubes.
Replaced R50 with a new resistor.
Still got vertical collapse. - I guess I could work backwards from 6DT5?
Set the line voltage to 117v AC.
When checking 6DT5 I got the following voltages:
- Pin# 1 280.1v (spec is 275)
- Pin# 7 20.52v (spec is 20v)
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Those voltages are completely normal. With line voltage set to the same 117V as Sam's anything within +/-25% is normal (in stages like vertical or CRT gun grid/cathode where the bias is controlled by potentiometers the normal range can be much larger than 25% and it's sometimes wise to adjust the relevant pots to make sure they can get the voltage that sam's says should be there.
If all the vertical voltages measure normal you may want to check the output transformer, and yoke and their connections to each other.