Last problem here - I need a 6CE3/6CD3/6DT3/6DU3 damper tube.
There is a 6BW3 in it now, and I noticed a light green glow in the cathode--plate region.
At one point, I heard a snap and lost raster breifly, only then I noticed the incorrect tube.
NFW am I running it now, until I get the right tube and risk losing the NOS 6LR6.
What is odd here is that the basing diagram is the same, but the Sams Tube Substitution book No. 18 lists only 6CD3/6DT3/6DU3.
Per the 1981 RCA tube handbook, most characteristics are equal between the 6CE3 and 6CG3/6BW3 except heater current; 2.5A vs 1.8A and plate dissipation; 11 w vs 6.5 w.
Of course I have no NOS tube so I have to dig deep in my pre-sorted bins and hope for the best...and I found 3! plus 5 34CE3's.
Put a used Sylvania 6DU3 into service, no green glow and HV up to 30 kV.
Increased R440 to 22 meg and HV drops to 27 kV, turn up the brightness (Sams HV adj procedure is to measure HV with normal viewing brightness) and it lands on 25, with control at minimum.
This has to be done!
Attachment 186707
Attachment 186708