Hi all,
Actually, I've had little chance to work on it all fall until this week.
Anyway, I found a step by step troubleshooting plan over at 18watt.com that I've been going through and as far as I can tell everything looks kosher until I go to turn it on and there is no sound.
In anycase, I've measured my voltages again with all tubes in, speaker connected and standby off..
Comparing my results to the chart in my manual they don't look too far off but when I compare them to this chart
HERE, it looks like something may be up with my preamp stage. Although I should point out that I'm aware the sIII schematic has a gain pot on the TMB channel that is missing form some other 18 watt schematics and this may be why...
Anyway, here is what I measured with the voltages suggested by my manual in brackets:
V1 12AX7
Pin 1: 150 (155)
Pin 2: --
Pin 3: 0.87 (1.0)
pin 4: H
pin 5: H
pin 6: 145.5 (155)
pin 7: --
pin 8: 0.92 (1.0)
pin 9: H
V2 12AX7
Pin 1: 152.3 (180)
Pin 2: 0
Pin 3: 1.18 (1.5)
pin 4: H
pin 5: H
pin 6: 249 (272)
pin 7: 152.2
pin 8: 152.8 (180)
pin 9: H
V3 12AX7
Pin 1: 200 (220)
Pin 2: 46.5 (52)
Pin 3: 70 (75)
pin 4: H
pin 5: H
pin 6: 202.7 (217)
pin 7: 47.7 (62)
pin 8: 70.2 (75)
pin 9: H
V4 EL84
Pin 1: --
Pin 2: --
Pin 3: 11.1 (12)
pin 4: H
pin 5: H
pin 6: --
pin 7: 327.4 (345)
pin 8: --
pin 9: 316.9 (340)
V5 EL84
Pin 1: --
Pin 2: --
Pin 3: 11.2 (12)
pin 4: H
pin 5: H
pin 6: --
pin 7: 327.8 (345)
pin 8: --
pin 9: 318 (340)
V6 EZ81
Pin 1: 287.5AC (292)
Pin 2: --
Pin 3: 337 (350)
pin 4: H
pin 5: H
pin 6: --
pin 7: 287.5AC (292)
pin 8: --
pin 9: --
I do notice that pin 2 of V2 has the shielded wire from the gain pot and I read 0 on that pin - is this normal?
So back to square one, any suggestions of where to go from here?[/url]