H T Supply Rectification & Pre-regulation Board

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FS2 250 mA

Anode & Screen Current Limiters Board

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oR31R30

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TR9

+

-C11

Audio Oscillator

Bias Supply Board

Leakage Detector

R32

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RL 1A

-

+

C10

D11

D10

D8 D9

R26

R25

R24

D7 R

23

R21

TR7BC307

R22

R14

R15

R18

D6

+

R20

R17

R16

bec

R19 ZD10

+

C7

C8+

-

C9+

-

C4

C5

C6

R27

C3+

-

w yx

Grid VControl

VR3

LeakageB3

VR1

VR2

+

-C 1

D 1

D 2

D5

D3

D4

R2

+

-

ebc

ZD1 ZD2

ZD4ZD5ZD6

ZD3ZD3

ZD7

be c

c be

TR8MJE 350

TR1MPSA92

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D

S

ebc

R5

R6

ZD9

ZD8

G

D

Sebc

R9

R10

ZD12

ZD11

TR4BUZ80A

TR5MPSA42

TR5MPSA42

R12

D16

Anode Supply &Current Meter -

CurrentMeter +

GM Meter -

HT LED

GM Meter +

CurrentControl

R1

C 2

grid feed0v

-

R3 R4

Anode HTSelector in

Screen HTSelector in

R12

HT to currentlimit board

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to HT supply boardselector switches

High voltage

Ground 0vto selectorswitches

0v Ground &Cathode supply

R11

TR2BUZ80A

R13

AC

AC35v

AC

AC

250

250

LeakageLED

Screen Supply

TR9BC237

TR7BC307

+

-C13

D2AD

1A

R11

C12

+-

B2

B4