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Tube Audio Pre-Amp Circuit with ECC82

Pre-Amp Tube Circuit

Pre-Amp Tube Circuit

Preamp Part List
R1-7=1Mohm
R12-13=100ohm
C9=4.7uF 250V*
R2=100Kohm 1W
C1=220nF 250V*
U1=ECC82
R3-8=1Kohm 1W
C2=220pF ceramic or mylar U2=ECC81
R4=1.2Kohm 1W
C3=2.2uF 350V*
RV1=2X100Kohm log.
R5-11=5.6Kohm 2W
C4=1000uF 16V
RV2=2X100Kohm lin.
R6=100Kohm
C5-6=2X50uF 450V
RL1….6=Relay 12V 2X2 [1A] 
R9=22Kohm
C7=1uF 250V* 
R10=100Kohm
C8=220nF 630V *polypropylene or MKT

Power supply Circuit

Power supply Circuit

Power suply
IC1-2=LM317*
R1=2.2Kohm 5W
R2-4=100Kohm 2W
R3=680ohm  5W
R5-6=220ohm
R7=470ohm  1W
C8-13=10uF 16V
C1=33nF 630V
C2…..5=2X50uF >350V
C6=4700uF 25V
C7-9=100nF 100V
IC3=7812  [1A]
C10-15-19-20=47uF 25V
T1=230Vac / 200V 0.15A
C16=470uF 25V
T2=230Vac / 12V 3A
C17-18=100nF 100V
F1=0.2A slow
BR1=4 X 1N5408
BR2=4 X 1N5408
BR3=4 X 1N4007
F2=0.1A fast
TR1-2=4.7Kohm trimmer
S1= Switch 2X2 10Aac
RL7=12Vdc Relay 2X2 10A
D1…..7=1N4007 EMI RF Filter 230Vac/6A
D8=12V 0.5W zener * with heatsink

Input Selector - Delay Drive Circuit

Input Selector - Delay Drive Circuit

Input Selector – Delay Drive
R1…..5=1.2Kohm
R6-8=1Mohm
R7-9=10Kohm
R10-11=1.2Kohm
C1=100nF 100V
C2=10uF 25V
C3=22uF 25V
Q1-2=BD679
IC1=4081
D1……5=3mm Red
D6……9=1N4148
D10-11=3mm Green LED
LED S2=SEL 1X6 step
S3=1X2 mini switch

Posted in Power amplifier, Sound Circuit.

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