Operation 2 - Heathkit HR-1680 Manual

Geer AcHKITS
OPERATION
Refer to Figure 4-1 (in the "Illustration Booklet") for the loca-
tion of the front panel controls and switches referred to in the
following paragraphs.
TUNING DIAL
BAND switch 40 (7 MHz)
Dial reading 35 kHz
Frequency 7.035 MHz
ZERO SET
AF GAIN
RF GAIN
BAND
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quencies in MHz when the tuning dial is set to zero (0):
80 3.5
40 - 7
20 14
15 21
10A 28
10B 28.5
PRESELECTOR
Tunes the RF amplifier stages. Readjust this control for
maximum signal on each BAND as the main tuning is
changed.
PHONE
- Connect low impedance headphones (or high sensitivity, high
impedance headphones) through a phone plug. When you
insert a plug in this jack, the loudspeaker is automatically
disconnected.
NOTE: Ifyou use iow impedance headphones, you may notice
ahum at low volume levels. Add a 100 0 resistor (not supplied)
in series with your headphones to reduce this hum.
MODE
Place this switch in the appropriate position for lower
sideband, upper sideband, or CW reception. This switch also
selects a slow AGC time constant in the sideband positions
and a fast AGC time constant in the CW position.
FUNCTION
Place this switch in the desired bandpass position (either
narrow or wide). Place the switch in the calibrate position to
turn on the 100 kHz crystal calibrator for dial calibration.