Heathkit HD 1982 Schematic 2

Page 1

WAVEFORMS

CIRCUIT BOARD *1

9V
+ II - 65: r " ,
J) SWIOI I 1
M T

TRANS.4-> REC.

$525)

.__.@ .q 15? ®
3 Low TONE 11,

OSCILLATOR

I fill?
an

mu
Ian

3 MICROPHONE

CONTROL
CIRCUIT

AUDIO

GROUND

'ch Em
$ Ia gm

ICIOZ

r--_--_--_--------.---.----..-.....--------------..--_.-.------'

44253®¢N N 1
HIGH TONE : 0 ES
OSCILLATOR ,
I I. REFER 10 THE "CIRCUIT BOARD x»RAY VIEWS" FOR THE
W : PHYSICAL LOCATION or PARTS.
I
W : 2 PRECISION RESISTDRS AR: 118 Mn, 17- TOLERANCE.
I REMAINING RESISTORS ARE 1/4 WATT, 10$ IOLERANCE.
: RESISTOR vALuEs ARE IN OHMS (-1000, M-IDOMODL
l
I 3. CAPACITOR VALUES ARE IN NF.
___________________________________________ _--_--.-------------------J

4. DC VOLTAGE MEASUREMENTS WERE TAKEN WITH A HIGH
INPUT IMPEDANCE VOLTMETER FROM THE POINT INDICATED

SCHEMATIC OF THE T0 CIRCUIT BOARD GROUND. VOLIAOEs MAv VARv 210$.
HEATHKIT) 5, O THIS'SVMBOL INDICATES A Dc VOLTAGE WITH NO
TONE BEING PRODUCED,BUT PTT SWITCH swm DEPRESSED.
MICODER'"
o - 6. :1 THIS SYMBOL INDICATES A no VOLTAGE WITH KEY
EC n WWII. MODEL HD'1982 "1" PUSHED AND 911 SWITCH swm DEPREssED,
5 Yum/NM was ms Im
W . 2 3 comm©m 7 V THIS SYMBOL INDICATES CIRCUIT BOARD GROUND.
no I s s mm
In... suonvzo :33 I g : Allklghtshuorved a. 0 THIS SVMBOL INDICATES A CONNECTION TO THE CIRCUIT
42,533 MW '5 immune amp,
mum .. N cm or Ransom pms mwmmmousmmwMmmw
9. THE WAVEFORMS SHOWN WERE OBTAINED av PUSHING

KEY "1" WITH PTT SWITCH SWIM DEPRESSED,