S" Meter Zero Set; Operation; Bandswitch; Bandspread - Hallicrafters SUPER SKYRIDER SX-28-A Instruction Book

stand-by switch. If the remote stand-by switch or relay
is connected between pins
#
1 and
#
5 on the shorting
plug and the SEND-RECEIVE switch on the front panel
of the receiver is set at SEND, the remote switch or relay
will control the operation of the receiver in the same
manner as the SEND-RECEIVE switch.
(5)
"s"
METER ZERO SET
"S" METER CONTROL is obtained by varying the
knurled
~nob
appearing on the left hand chassis apron
edge. ThIS control enables you to properly set the . 'S"
Meter to zero. In order to make the adjustment correctly,
the RF GAIN CONTROL must be advanced clockwise
as far as it will go. In addition, the switch directly below
the bandspread hand-wheel must be in the A VC-ON
P~sition.
When these conditions have been complied
wIth, remove the antenna from the Receiver and then
adjust the S meter control until the S meter reads zero.
Reconnecting the antenna to the receiver will then make
the meter indicate the relative carrier strength of each
incoming signal as various signals are tuned in.
B
OPERATION
Each control of the Model SX-28-A SUPER SKYRIDER
receiver performs a definite function that contributes to
the outstanding reception capabilities of the unit. Full
appreciation of the receiver is to be expected only after
you have become familiar with each of the controls and
the effect their operation has on the receiver's perform-
ance.
The large calibrated main dial shows the frequencies
covered throughout the 6 band, 550 kc to 43 mc fre-
quency range of the reciever. They are as follows:
Band 1-550 to 1,600 kilocycles
Band 2- 1.6 to 3.0 megacycles
Band 3- 3.0 to 5.8 megacycles
Band 4- 5.8 to 11.0 megacycles
Band 5- 11.0 to 21.0 megacycles
Band
6--
21.
to
43. megacycles
. (1 )The BAND SWITCH, directly below the main dial, will
place the proper set of coils in the circuit to cover the
desired frequency. The main dial is turned by the large
handwheel which is equipped with a micrometer scale
for maximum accuracy in resetting or logging puq_)ses.
Of particular interest is.the locking clutch which will be
found directly below the handwheel. This feature will
aHow you
to
lock the main dial after a desired signal
has been tuned in. Subsequent movement of the hand-
wheel will not detune the receiver because the control is
provided with a clutch which disengages the handwheel
once the dial lock has been set.
The International Shortwave broadcast bands are indi-
cated on. the main dial by heavier lines showing the
frequencies on which these transmissions will be heard.
The Amateur band setting positions of the main dial
are indicated by a '>mall 0 appearing over the red numbers
which identify each amateur band. The hairline on the
main dial window should be set so that it intersects this
small circle when the main dial is placed in position for
the desired amateur band.
(2)The BANDSPREAD dial is calibrated for the 10-20-40
and 80 meter amateur bands. When tuning on the 160
meter band the main dial should be used.
Note: The calibration on the main dial will be accurate
on~y
if the bandspread condenser is set at minimum capac-
ity which is indicated by a setting of 100 on the band-
spread logging scale. It should be recognized that if the
bandspread condenser is left at any other setting but 100,
that small amount of bandspread condenser capacity,
added to the main tuning condenser capacity, would
throw off the main tuning dial calibration because the
receiver is calibrated with the Bandspread condenser set
at minimum capacity. The portions of the amateur bands
on which type A3, or telephone, transmissions will be
heard are underscored with another dark line.
The numbered outer edge of the bandspread dial will
prove to be of grea(help for logging or pre-setting pur-
poses when the bandspread tuning control is used for
easier tuning on frequencies other than those covered bv
the amateur bands.
When "bandspreading" any frequency throughout the
tuning range of the receiver remember the main dial must
then be set to a slightly higher frequency than the de-
sired signal. The difference depends on the amount of
bandspread condenser capacity used and the frequency
of the received signal. .
When switching from one range to another, an indi-
cator moves vertically behind both the main and band-
spread dials. Tuning fatigue is thereby greatly minimized
by focusing attention on only the frequencies covered
hy
that particular setting of the bandswitch.
The translucent, indirectly lighted dials are easily read
and so arranged that parallax is reduced to an absolute
minimum.
To operate the ,receiver adjust the following controls
in the order in which they are mentioned:
(3) The TONE CONTROL turns the receiver on and off
and in addition emphasizes either the base or treble fre-
quencies to the extent required by various receiving con-
ditions. The effect the Tone Control has on the fidelity
of reproduction is shown in Fig. 10.
( 4) Place the SEND-RECEIVE switch in the RECEIVE
position-have the ANL control off (turned to the left
until the switch operates).
Place the bandswitch in position. 55
to
1.65 mc, which
will then enable you
to
tune in stations on the standard
Broadcast Band .
(5) Rotate the RF GAIN control to the right until #9 on
the skirt of the control appears under the panel marker.
(The RF Gain must be full ON as above indicated before
the S meter will indicate correctly.) So that the S meter
will be properly connected in the circuit, the AVC-BFO
switch appearing to the lower right of the bandspread
handwheel, must be in the AVC ON position.
( 6 ) Note: The A ntenna Trimmer control is operated on all
Bands. Proper adjustment of this control is indicated by
the maximum signal.
(7)Afrer complying with the above conditions, the AF
GAIN control should be advanced to the right until the
desired volume is obtained. Tuning the receiver by oper-
ating the main dial handwheel will now allow you
to
pick up stations throughout the .55 to i.65 me tuning
range of the Broadcast band. Maximum deflection of the
S Meter will indicate when each station is accurately
tuned in.
When covering the short-wave or higher frequency
bands the above procedure should be foHowed-except
that greater care should be used because it is so easy to
completely pass over a station. . .
The other controls on the model SX-28-A SUPER SKY-
RIDER receiver will enable. you to obtain the best results
- 5 -