Hammarlund HQ-180 SERIES Technical Description And Operating Instructions page 19

HQ-180A OPERATION
With the antenna, speaker and any accessories installed, you are ready
to receive transmissions on the amateur bands. These pages are intended to
show you the operating methods that will permit the Receiver to give you the
best audible signal possible, considering atmospherics and man-made noise.
Three most important reminders:
1. Check the listening aids like the noise limiter and slot
frequency control -- be sure incorrect setting is not
reducing Receiver capability.
2. Always tune the Receiver properly to produce the maxi ­
mum signal.
3. Don't forget the antenna trimmer -- it requires a different
setting on each band. This is because antenna impedance
changes with frequency; the trimmer is there to allow for
a maximum match at all frequencies.
Plug the Receiver line cord into a 117-volt, 60-cycle line (the export
model HQ-180A
-E
will accommodate 117 or 230 volts, 50 or 60 cycles). Turn
the Receiver on, using the RF gain control and the c Lock timer switch if in ­
stalled. Check that all tubes are lit. Note that the high-irequency oscillator
and mixer tube filaments remain heated at all times, (in the HQ-180A series)
if the line cord is left inserted into a source of AC power. Heating of these
tubes eliminate drift that occurs in all oscillator circuits as they heat up.
Tube life is not reduced through continuous operation. In fact, its life is often
extended to many times normal because it is not subjected to the hardships of
physical expansion and contraction due to heating and cooling when power is
applied and removed. If the receiver is not to be used for extended periods
(upwards of 3 days) the line cord should be removed from the power socket.
If the oscillator has not been maintained heated, then allow one hour for the
Receiver to settle down to a steady tuned condition. Readjust tuning as neces­
sary during this period. Do not attempt to calibrate or set the S-meter until
drifting has stopped.
The HQ-180 and "A" Series Receiver is arranged to provide t.he best
reception for AM (voice), for Code (modulated or unmodulated CW), and for
SSB (single sideband) operation. To be sure of the best results and the
clearest reception, read all of the instructions presented here. Set the con­
trols as shown in each illustration for normal operation, and follow the guide­
lines to improve performance and to tune over the bands. Become familiar
with each control and see what each can do for you. Even after you are familiar
in every way with the controls, refer occasionally to these instructions to
check that you are still getting the mo st out of the many features of the HQ-180A.
Finally, your particular location and installation will affect operation;
experiment with control settings to obtain the best results. And consult with
us if there are any problems. The Receiver is for your enjoyment use it
correctly and it will give you years of service. '
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