Viking Valant 2

<< < (2/2)

N1BCG:
Quote from: w8khk on October 11, 2017, 02:45:22 AM

More effective to short the filaments of the 866s to ground.

You are absolutely correct, and it demonstrates why cross-checks from a separate set of eyes are invaluable. Shorting the plate caps of either the RF or AF 6146 tubes to the chassis would also work.

The resistance should be about 40k Ohms, which is the sum of the voltage equalizing resistors across the HV caps.

k7pp:
Might I suggest that shorting the plates of the 6146 finals to ground to discharge the filter caps might blow your plate choke wide open.
Shorting the modulator tube plates to ground risks your modulator iron as well.
Keep in mind that there are three power supplies in the Val.   High voltage,  low voltage and the bias supply.
Might I recommend locating the individual filters in the transmitter and shorting them directly to ground.   
Better safe than sorry???   Just sayin'.

KE7KPB:
The transmitter has never been touched. I did do a complete electrolytic capacitor replacement using 105c caps. i even watched the one where the + side was going to chassis. The 866 tube in the front was the one doing the sparking and the meter was on plate and it wanted to bury its self. I'm going to pull the 6146A out and test them on my 539C.
This is great information now to print and go to work. I will keep you informed as to what I find. :D

WD5JKO:

The 866's might be bad, or at least one of them.

There are several SS replacements on Epay right now. Look for 1N2637.

Jim
Wd5JKO

Navigation

[0] Message Index

[*] Previous page