Hammarlund HQ-100A Series User Manual page 9

m
dial and tuning in the signal with the MAIN TUNING
control. Final peaking of the signal is then accom­
plished by adjustment of the BAND SPREAD control.
It should be understood that the setting of the BAND
SPREAD control will affect the Main Dial calibration
in that a higher frequency setting of the main tuning
dial will be required. Rotating the band spread dial
from 100 toward 0 tunes the receiver to a lower
frequency.
For Band Spread operation in the amateur bands, the
following procedure must be followed: The main tuning
dial is set to the line marking the high frequency (right ­
hand end) of a given amateur band. The Band Spread
tuning and calibration may then be accomplished solely
with the BAND SPREAD control and dial.
20BS
SWITCH POSITION
A separate switch position is provided on the
TUNING RANGE control for spreading the 20-meter
band. This switches in another band spread capacitor
for optimum spreading of this band.
TElECHRON AUTOMATIC TIMER
If
your receiver is equipped with the built-in 24
hour Telechron Automatic Clock-Timer, the following
instructions should be noted:
Every radio-frequency device is stable only at pre­
determined operating temperatures. In order to elim ­
inate waiting for receiver to warm-up to operating
temperature,' the Telechron'Timer automatically turns
on the receiver ahead of anticipated operating time.
This is accomplished by setting the hand of the timer
(small knob at rear of receiver) to approximately one­
half hour before operating hour. The front panel con­
trol under Timer is then set to "Auto" position. The
function switch is set to REC. The receiver is then
automatically turned on at the desired time.
The clock hands are set by the rear knob. Push in
on the knob to set the switch timing hand and pull out
on the knob to set the clock hands. The front switch
is setto AUTO and the operation switch is set to REC.
when it is desired to use the automatic clock switch
for pre-warming the receiver before operation or for
use as an alarm to turn the receiver on to a pre-tuned
station. To use the operation switch normally, the
clock switch should be left in the ON position.
The clock will continue to run as long as the receiver
line cord is connected to the power outlet, and is ex­
tremelyusefulfor checking sign-in periods and sched ­
ules.
If your receiver is not equipped with the Telechron
Automatic Clock-Timer, and you would care to have the
accessory added, clock kits, with full installation
instructions. may be had by writing
Harnmarlund Manufacturing Co.
73-88 Harnrnarlund Drive, Mars Hill, North Carolina
or by contacting the nearest Harnrnarlund dealer.
POSSI BlE RECEIVER 01 FFI (UlTI ES
1. If, upon turning the function switch from "off" distortion is preferable to excessive pulse type
to "receive" position, the dials are not illumi ­ noise, such as ignition interference.
nated and the receiver fails to operate after two
minutes, this indicates that the clock timer
3. Erratic S meter performance, lack of sufficient
switch just above the function switch is nat·in variation, etc., is usually due to the two 6BA6
the proper position. This switch should always tubes employed in the S meter circuit. These
be in the ON position unless auto timer is em ­
are the tw06BA6tubes, V5 and V6, in the sche ­
ployed. matic diagram. Merely interchanging these
tubes will sometimes provide sufficient im ­
provement. Replacing one or both may be found
2. Excessive hum or failure of the Qmultiplier to advisable before suspecting other troubles.
operate properly will usually be due
to
a de ­
fective 12AX7 type tube. Such a defective tube 4. Excessive drift, after allowing sufficient time
may test good in a tube tester but be unsatis ­ for warm up, may be due to a poor type 6C4
factory because of higher than normal heater ­ tube, V3, in the diagram or 6BE6, V2, in the
to-cathode leakage. Poor noise limiter action schematic diagram.
is usually due to a poor or defective 6BV8 type
tube. The use of the noise limiter will result in Ninety-nine percent of all receiver trouble has been
some distortion which must be tolerated for found to be due to one or more defective tubes. This
most efficient noise limiting. Because
of
this" can undoubtedly b e attributed to the rough handling
when listening to broadcast stations or oth'er equipments receive in shipment. Please, therefore,
strong local signals, the noise limiter switch be sure to follow the above suggestions in addition to
should be in the "off" position unless the slight haVing all tubes tested before writing the Home Office.
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