Page 32
INITIAL TEST AND CALIBRATION
This and the following section are concerned
with adjustments and tests which must be per-
formed before your HW-30 is put into use.
THE TRANSMITTER ALIGNMENT PROCE-
DURE MUST BE STRICTLY FOLLOWED TO
THE LETTER, OTHERWISE OUT -OF -BAND
OPERATION CAN RESULT!!!
IT
SHOULD BE NOTED HERE THAT AN
AMATEUR RADIO OPERATOR AND STATION
LICENSE IS
REQUIRED TO PLACE THIS
TRANSCEIVER ON THE AIR. Information re-
garding licensing and amateur frequency allo-
cations may be
obtained from publications
of
the Federal Communications Commission
or the American Radio Relay League.
The HW-30 may also be operated as a CAP
(Civil Air Patrol) transceiver in accordance
with
appropriate FCC and CAP Regulations
available from Government Printing Office,
Washington, D.C.
RECEIVER AND AUDIO SECTIONS
(
) Begin by checking the power supply for
short circuits. An ohmmeter, with posi-
tive probe on pin 5 of the power connector
and negative probe on the chassis, should
read 150 KS/ or above, within one minute
while
allowing the
filter
capacitors
to
charge.
(
)
The power supply output voltage will be
checked next. Connect the 117 volt power
cord to the power connector. Plug the cord
into a source of 105-125 V 50/60 cycle AC
only, and turn the power switch ON. Meas-
ure the DC voltage developed between the
blue lead of the audio output transformer
and ground. This voltage should be be-
tween 290 and 320 V DC. After making
this measurement, check the clear neon
"power" lamp for illumination to deter-
mine
it's
proper functioning.
With the
TRANSMIT -RECEIVE switch in either of
the two "TRANS" positions, the red neon
"TRANS" lamp should also light. Now turn
the unit off.
(
) Install all tubes V1 (12AX7), V2 (6AQ5),
V3
(6BS8), V4
(6BA8), and V5 (6BA8).
See Figure 8.
) Set
the TRANSMIT -RECEIVE switch to
the RECEIVE position, and TUNING control
to full counterclockwise end of rotation.
Rotate
the REGENERATION control on
the rear chassis apron full counterclock-
wise.
Turn the unit on and advance the VOLUME
control until the knob pointer is vertical.
Now, slowly advance the REGENERATION
control clockwise until a
"hissing"
or
"rushing" sound is heard in the speaker.
The correct setting will be the minimum
clockwise position at which the receiver will
remain in
regeneration over the entire
tuning range. This setting will require re-
adjustment later during receiver alignment
and is not critical at this point.
If
the above steps have all produced the
desired effects, turn the transceiver OFF
and go on to the following section. If any
difficulty was encountered in the foregoing
tests, refer to the IN CASE OF DIFFICULTY
section on Page 40.
TRANSMITTER SECTION
Proper alignment of the transmitter section is
extremely important, otherwise off -frequency
operation can result. A brief review of the
transmitter section circuit description starting
on
Page 4
will prove helpful at this time.
To further stress the above point concerning
proper alignment, let us look at an example of
what can happen through improper adjustment.
IN THE FOLLOWING EXAMPLE, AN 8.000 MC
CRYSTAL REFERENCE FREQUENCY WAS
USED FOR EASY CALCULATIONS.
For normal operation, the coil in the oscil-
lator plate circuit Ll, should be resonated at
24 mc. This coil has a considerable range and
with the slug turned all the way in, it will tune
near 16 mc. With the coil slug backed out all
the way (with the screw thread at maximum
height above the chassis) Ll will tune near 32
mc. Let us assume that through improper align-
ment, the circuit is resonant at 32 mc instead of
24 mc.
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