I finished my Rocket "Ryann Leslie" (daughter) last night and had a chance to fire it up today.
Ran all the usual checks without then with tubes and used a bulb limiter- all was OK.
I got rid of the limiter and checked everything out:
Secondaries: 506V
B+1: 298
B+2: 289
B+3: 220
B+4: 197
B+5: 189
Bias voltage: 9.1V
V1b Plate:125V, Cathode:.878V
V1a Plate: 90V, Cathode: .679V
V2a Plate: 194V, Cathode: 125V
V4 & V5 Plate: 289.6V Cathode: 9.07V
V6 & V7 Plate: 290.5V, Cathode: 9.07V
The Cathode voltages on V1 had me really perplexed.... so I re checked the layout on the Preamp board, re checked continuity on all wire and connections- all was OK... I did however catch that the board mounting #6 machine screw by the input jack was touching the turret for the wire from the input jack... thought that might have been it...
Rechecked all voltages again and gor the same for the V1 plates..... so now I'm thinking that either this is what I should be seeing, or something really stupid has happened in the build (wrong wire, wire wisker shorting to ground, whatever). The amp was pretty quiet, but enough hiss to know it was breathing.
So I figured that I would just go ahead and try it with a guitar.... and it sounds amazing... it's not as hairy as an Express, but dimed, it is every bit its peer.
So I must now conclude that due to my electronic ignorance, it's supposed to have these low cathode voltages, but I'm probably wrong...
So Skyboltone, Allyn, Dana, Jana, and all of you that know a hell of a lot more than I do, what's the deal here- is it right? if it's not, it sure sounds good for a screw up....
Many thanks in advance!
Ron
New Rocket build
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