Heathkit GR-78 - Page 31

re =
TROUBLESHOOTING CHART
DIFFICULTY
POSSIBLE
CAUSE
Initial
resistance
check
“Trimmers
installed
upside
down
shown
short
lrult
Powersupply
8
ereult
shorted
to
round,
Solder
bridge
betwaen
fol
on
eruit
board,
“Trimmer
capacitors
shorted
to
adjacent
foil
ceiver
dad,
Shorting
springs
not
removed
from
O01,
0201,
‘or
040
Deod
battery,
equites
carga.
Shorted
Br
crit
Mute
jumper
not
conecte,
RGV/STBY
switch
in
STBY
pation,
Low
sensitiv
‘Low
battery
voltage,
requires
charging
Receiver misaligned.
53,
Trimmer
captors
shorted
to
adjacent fils
Transistors
101,
0201,
0301,
0401,
and/or
A405
Installed
incorrectly
Sound
distorted
Low
batary
voltage
Received
signe
stored
‘AF
of
RF
gain
contol 8
o0
high
‘Tranwiort
0408
or
400
Distortion a strong salons 1. See "Sound distorted."
2, AVCawitch in MVC position,
1, Too cote to tion.
Nosy when tuning or daa at one 1. Tun eapeltor plates bent o diy.
fee onal bans,
‘Singlesideband signal sound 1, Sigal not tuned n propery.
ow
or
igh
pitched
2,
Tranaformer
T401
not
alone
propery,
‘Atow how from the speaker 1. Flat bead connected to tuning capacitor not fexble,
‘on
trong
stations,
especially
2;
Lead
trom
bandipreed
capacitor
to
turing
eapecitor
too
on Bands E and F. rong
Tuning mater inopeatve, 1, AVC switch in MVC position.
2, Resistor R408 misused
2. Mater
1. Low battery voltage
2, Resistor RID4 wrong valu