Well I finally gave in and built myself a sIII, I mostly sourced the parts , and used what I had. I followed Stephan's Schematic and layout. It DOESN"T squeal. Normal channel is nice and quit and very minimal noise/hum.
However TMB channel has hiss sound that increases with volume, treble control. ( I skipped master volume and it is connected straight to the C6 0.022uF and then to PI). So Any recommendation would be appreciated.
As far as the boost switch, I used a 3 position switch, so I had one position, just a 1500 Ohm, next one a 1500 and a 22uf and the third position makes it a 750 Ohm and 0.68uF.
I wouldn't source parts next time, cause it would be actually better to just buy it off of him, too much hassle and in the long run not worth it.
Right at the transformer out and First filter cap it is 339 V. Power dissipation is 11.23 Watts ( I think).
Voltages:
V1:
Pin 1: 150
Pin 3: 0.885
Pin 6: 142.7
Pin 8: 0.946
V2:
Pin 1: 160
Pin 3: 1.258
Pin 6: 261.2
Pin 8: 160.9
V3:
Pin 1: 206.3
Pin 2: 52
Pin 3: 75
Pin 6: 208
Pin 7: 53
pin 8: 75
The two EL84s (V4 and V5):
Pin 3: 12.33 ( I used 150 Ohm and 1000uF)
Pin 7: 338
Pin 9: 323
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