Heathkit AD 1305 Schematic

Page 1

INPUT AMPLIFIER

IBV
. i FREQUENCY CONTROL
LEFT- CHANNEL YEL .63 _' g R8
INPUT 4 4
TAPE MON
I" ______________________________
TAPE OUT
ON? :32 385 ER?» 23"!
K
TAPE MON m -i
GRN ' C103 x 004 CIOSV I
H, 5 F 4).)?" IIpF '27
t 2 I R 06 R 0
+1- 5N6, Ergo 22407
(.702...
270 T" 0/ L102 L103
\j IJSH 405mH 94mH
O O O

RIGHT CHANNEL

INPUT "7
TAPE OUT OFF
ON WHT
TAPE MON BM SW203
TAPE MON

SCHEMATIC OF THE
HEATHKIT®

AUDIO EQUALIZEFI
MODEL AD-1305

VOOpyrIgm © I975
Heath Company
All Rights Reserved

4. SWITCHES ARE SHOWN AS FOLLOWS:

TAPE MON-OFF.

TONE FLAT-OFF.

POWER-OFF.

ALL FREQUENCY CONTROLS-CENTER OF RANGE.

NOTES:

1. PARTS ARE NUMBERED IN THE FOLLOWING GROUPS:

1- 99 ggiTRSDON THE EOUALIZER CIRCUIT 5. V THIS SYMBOL INDICATES A CIRCUIT BOARD GROUND.
101-199 SARA?) ON THE CONTROL CIRCUIT 6. 5 THIS SYMBOL INDICATES A CHASSIS GROUND.
201-299 PARTS ON THE CHASSIS. 7. 0 THIS SYMBOL WITH A LETTER 0R NUMBER IN IT
INDICATES A WIRE CONNECTED To THE CIRCUIT BOARD.
2. ALL RESISTORS ARE 1/2-WATT 5% UNLESS MARKED OTHERWISE.
RESISTOR VALUES ARE IN OHMS IK=1000. M=1.000.000.I 3. 0 THIS SYMBOL INDICATES A POSITIVE DC VOLTAGE

MEASUREMENT TAKEN WITH A HIGH IMPEDANCE VOLT-

METER FROM THE POINT INDICATED TO CHASSIS GROUND-
VOLTAGES MAY VARY i 20%.

3. CAPACITOR VALUES LESS THAN 1 ARE IN UF. VALUES OF 1
or GREATER ARE IN pF, UNLESS OTHERWISE MARKED.