Scully 280B Series - System Block Diagram

6-2
Model 280B
Theory of Operation
SQUELCH
r-------- - - - ,
I
REC LIGHT
I
~---------- --'
LOGIC
REC STATUS
+25V~~ --~ ~ .---- -- ~ -- ~
+2 5 V '- ___ +_ -----,
PL AY BACK r ~ .::>R,----.,6__o , 7 - +---1 f__ _j
HEAD ~ 5 '
POWER
SUPPLY
- 40 V
'--r---' UN REG
117 VAC
.i SYNC:
+25V
-25V
REL
PLAY 3
EQ 2
tJll
LINE IN '---- ...... --1'
+25V
PLAY
0
C AL
~ ER IlLUM
+-25V
BIAS
ADUST
SQU ELCH F UN C TI ON
TIMING C
IR CU IT
FRONT
PANEL
AGC t
2009328
Figure 6-1. System Block Diagram