parts and PSU
Thanks for the reply. I used PSU Designer II and the parts list. Full listing of parts below, plus the calibration proceedure (where i worked out the fixed bias rating)
Rated Power Output: 35 Watts
Frequency Response: 20Hz - 20kHz (+/-2dB)
THD: 0.5% (1kHz/35W)
Signal to Noise: 65dB (Input Shorted)
Input Sensitivity: 300mV
Treble Control: +16 ..-20dB
Bass Control: +18 ..-20dB
RESISTORS:
R1,R5,R8,R12,R16 = 1M
R2,R14,R18,R24,R25,R26,R27 = 1k
R3 = 82k
R4,R7,R13,R17,R19,R20,R21 = 100k
R6 = 150k
R9 = 220k
R10,R32 = 2.7k
R11 = 10k
R15 = 470R
R22,R23 = 330k
R28,R29 = 100R/1W
R30,R31 = 10R/1W
R34 = 27k/2W
R33 = 470k
R35,R36 = 10k/1W
R37 = 56k/0.5W
R38 = 22k/0.5W
P1 = 5M pot. lin.
P2 = 1M pot. lin.
P3 = 0.5 pot. audio taper
TR1,TR2 = 100K trimmpot
TR3 = 100R/0.25W wire wound trimpot.
CAPACITORS:
C1 = 0.047uF/100V
C2,C10,C14 = 47uF/16V
C3,C9 = 0.1uF/400V
C4,C5 = 47pF/50V cer.
C6,C7 = 4700pF/100V
C8 = 300pF/50V
C11,C13 = 0.033uF/400V
C12 = 0.033uF/100V
C15,C16 = 0.047uF/630V
C17 = 680pF/100V
C19 = 47uF/63V
C20 = 100uF/500V
C21,C22,C23 = 47uF/500V
T1 = Output Transformer - no data available
D1 = 1N4148
Power Transformer:
Secondary: 2 x 300VAC 240mA
Filament1: 5VAC/2A
Filament2: 6.3VAC/4A
Filament3: 6.3VAC/2A
Tubes:
V1,V2 = ECC83
V3,V4,V5,V6 = EL84
V7 = GZ34
Calibration Procedure:
Make sure all wiring and connections are correct. Remove tubes V3 - V6 from sockets,
leave only V1 and V2 inserted. Short amplifiers input to common ground.
1. Set both trimmpots TR1 and TR2 in center position.
2. Turn on power and check voltage at TP1, adjust with TR2 to ca. -20.0 Volts. Next turn off power
and insert all power pentodes.
3. Turn on power and let the tubes warm up. Connect DVM between TP2 and TP3 (control grids of the
pentodes), adjust with TR1 to zero Volts. Set DVM to 1 Volt scale and reset again to zero Volts.
4. Next connect DVM to common ground and one of the pentode cathodes, adjust with TR2 to 1130mV
(1.13V).
5. Now connect DVM between the V3 and V4 cathodes and adjust with TR1 to zero volts, use lower scale.
6. Finally measure voltage between common ground and cathodes of V3 and V4 pentodes. Should be 1130 mV
+/- 20mV. Repeat steps 3-5 if needed.