Heathkit GDA 505 D Schematic

Page 1

EATVEIiV
CHARGER

120v
SOIWN} 72°.

"mun CABLE

5-OIAIIIE

SHEIITIC 0f Til
IIEATIIIIT
l DIGITAL PROPIIITIIML TIAISIITTER
IDIIEL ADA-505i

-.------__----___-_-------_-_ .or\--------- --_

mm.

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+ 4."
ELK
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FREE RUNNING
MuulvlaRAroR

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NOTES:

COMPONENT NUMBERS ARE IN THE FOLLOWING GROUPS:
- 99 PARTS MOUNTED ON THE ENCODER CIRCUIT BOARD.
101'199 PARTS MOUNTED ON THE TRANSMITTER CASE.
201- 299 PARTS MOUNTED IN THE BATTERY CHARGER.
301,399 PARTS MOUNTED ON THE SERVO CENTERING
STANDARD CIRCUIT BOARD. -

ALL RESISTORS ARE Ill-WATT. 10$ TOLERANCE UNLESS
OTHERWISE NOTED. RESISTOR VALUES ARE IN OHMS IK-IODDL

ALL CAPACITOR VALUES LESS THAN 1 ARE IN HF. VALUES DFl
AND ABOVE ARE IN VF UNLESS NOTED OTHERWISE

A
5

.OTHIS SYMBOL INDICATES A test POINT.

IOTHIS SYMBOL INDICATES A Dc VOLTAGE MEASURED FROM
m: POINT muncmn T0 CHASSIS. ALL vomcss wan:
MEASURED wnu A man mrur IMPEDANCE vonmmn.
vomsas my VARY :sz

ALL MEASUREMENTS WERE MADE WITH A BATTERY VOLTAGE 0F
9.6VDC.

1. REFER TO THE CIRCUIT BOARD XRAV VIEWS

FOR THE PHYSICAL LOCATION OF PARTS,

m *1 TRANSISTORS Q3 THROUGH :17
OPERATE m MONOSTABLE TIMER
cmcuns. 1H: WAVEFORMS
SHOWN FOR TRANSISTOR as
ALSO APPLY ton TRANSISTOR:
94 THROUGH Q7.