Motorola M3000 - Display Icons and Symbols

S2
I I BLK!i
5
0
j 3·o· RED
0150
ABW
REGULATOR
P4
PS
1~1.-5V_A_C+-9~:'-l 4: BLK
: :
: G:OYEL
~
1
: YEL-
_J BLK
I '
_____ ____, 3 >-- BLK -
';"'! [:t:::
1'>--YEL-
l _J BLK
S2
R153
3.3K
Rl54
1K
+ Cl508
~600
C153
.001
D154
05.1
'if.
LO
f-
""(/)
LO:::J
. -,
NO
0) <{
LO>
-o
a::.._
'if.
LO
4
)-- +70V
SS OUT
P5
SS SIGNAL
3
)-- GROUND
Figure 2. Power Supply Circuit
A temperature compensated zener diode, D 154, establishes
a fixed reference voltage at the inverting input to IC150.
Resistor R156 provides a bias current for 0154, which
establishes its operating point. Capacitor C153 is a high fre-
quency filter. Operating voltage for IC150 is derived from
a voltage divider consisting of R 152 and R 153. Compo-
nents R155 and C151 set the voltage gain of 0152.
An increase in output voltage will result in an increase of
voltage at the base of 0152 via the non-inverting input of
IC150. The change in base voltage wi II turn 0152 on
harder, reducing its collector voltage. This reduces the
forward bias to 0151, which results in less emitter current
for 0150. With 0150 conducting less, the output voltage
will be lowered.
S6 P6 LJOO
+70VIN --<4~~.---.--~.------.JWV--~
P1-7
+70V-<
OUT
SIGNAL SG PG
GROUND--<
3
.,_--1_ ..
+70V
TO VERT/
HORIZ
CIRCUITS
VIDEO AMPLIFIER
(Refer to Figure 3,)
The linear video amplifier consists of two stages, 0100 and
0101, which are connected in a cascade conbguration.
This common emitter-common base arrangement greatly re-
duces the effect of Miller capacity (when compared to a
conventional single transistor video amplifier/output stage).
A TTL compatible non-composite video signal, approxi-
mately 4.0 volts P-P, is DC coupled to the base of 0100 via
R 100. Resistor R 112 provides proper termination for the
high frequency input video signal. Capacitor C100 provides
high frequency compensation to maintain a flat response
when 0100 and 0101 conduct.
YEL
R1134701/2W
IN CRT LEADS
;-------~I ____ ....,
WHT
I SPARK GAP,
! I ALL PINS OF
- - - - -
1
CRT SOCKET
8
BLK
2
V1
CRT
Figure 3. Video Amplifier Circuit
4-21