Heathkit GR-54 - Page 10

BFO ADJUSTMENT
Set the Receiver front panel controls as follows:
BANDSPREAD, ,.... adjust for a 5 indication
on the Bandspread dial,
AF GAIN, os teeeeee adjust as necessary dur-
Sie = alignment,
RF GAIN, . 2. . oe oe eee ees full clockwise,
ANT TRIM, ... 2.22 ee22.e-. full clockwise,
MODE es @e#eeeeaepeeepeeeseeeenupenense#etentereeste AM,
BAND soe; @ ®@ @ Fe ee eegseseseegeeeseseereaeenee Cc,
MAIN TUNING eae eSe@eweeetzpeseseaesnrteeens 4.5 Mc,
AVC eeee8+8tepeweeeoeeesenrteeseteseneneenenrteer#rthne ON,
ANL, ste eeeeeeeseeeehereseteeee eee ee OFF.
OPR so , @ GBC Bese see eC ee eee Fea ee eee eS REC,
( } Connect the common lead of the signal
generator to the Receiver chassis and con-
nect the output lead to the ANT socket,
( ) Set the signal generator to 4,5 MC and the
imum mater ras fy
AAAMEEL SEL 2
() Set the signal generator output for a reading
between 3 and 4 on the tuning meter,
( ) Turn the signal generator modulation off,
~~
—
maximum meter reading,
|
—
Reduce the signal generator output or the
RF GAIN control for a meter reading of 3,
Peed
hee asl
He
Adjust the Bandspread dial pointer for a
Tre a=
Page
( } Turn the MODE switch to USB, A continu-
ous tone should be heard, If it is not heard,
adjust coil L18 located on the IF-audio cir-
cuit board, This coil should not have to be
adjusted more than one turn in either di-
rection before the tone is heard,
NOTE: In the following steps, coil L18 will be .
adjusted. for a zero beat, Zero beat can be
defined in the following way: As the coil is ad-
justed, the tone you hear decreases from a
high to a graduaiiy lower pitch, until no tone is
heard at all, This point where notone is heard is
called the zero beat point, If you continue to ad-
just the coil in the same direction, the tone will
gradually increase from a low to a high pitch
again,
( } Turn the MODE switch to AM and adjust
the Bandspread dial pointer slowly towards
10 until a meter reading of 2.5 is obtained,
NOTE: As the Bandspread is adjusted to-
wards 10, the meter response is propor -
Hanal ta the ervatal filter rasnanee Dur
tional to ihe crystal filter response, During
these adjustments, the BFO is set, first on
. one side of the crystal filter response slope,
and then on the other side, When the Mode.
switch is set in the LSB position, capacitors
C48 and C49 are switched into the BFOcir-
cuitry to move the BFO frequency to the
41 wide of the glans
OWer 5idé Of ine siope,
{ } Turn the threaded shaft of the 1-10 uuf
trimmer capacitor until zero beat is reached,
( ) Remove the Signal Generator leads from the
Receiver, .
This completes the alignment of the Receiver,