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Heathkit HD-1250 - Circuit Description and Schematics

Heathkit HD-1250
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CONDITION
POSSIBLE
CAUSE
2. Low or no meter indication
(brown coil installed, oscil-
lator level maximum).
Unit
operates
properly with red
coil
(Step 1).
1. Weak battery. NOTE: Brown
coil requires
higher voltage
than the other coils.
2. Defective coil.
3.
Defective grounding. Resol-
der
all
three braids to cir-
cuit board foils.
4.
Insufficient
shielding. Be
sure side panels
are installed
wiui on naruware
secure.
5.
Oscillator
transistor Q1 1
.
6. Resolder coil socket
connections.
3.
Low meter reading,
oscil-
lator level maximum.
1
. Weak battery.
2. Diodes D21 or
D22.
4. Intermittent meter fluc-
tuations during tuning.
1.
Capacitor C21 plates dirty
or
bent.
2. Washers
missing between tun-
ing capacitor and circuit
board. See
Pictorial
1-3
on
P3Q9
16.
5.
Meter pointer
does not
move smoothly
across
scale as
oscillator
level
control is
adjusted.
j
1.
Control
R1.
2.
Meter. Meter lugs bent.
j

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