Walter Drake SW8 - Manual (Page 15)

Rear Panel Description 9
1 2 3 4 5 6 7 8 9
FM / AIR ANTENNA 2
ANTENNA 1
EXT DC
INPUT
MASTER
POWER
SHORTWAVE
ANTENNA
SELECT
FM / AIR
ANTENNA
SELECT
LINE
AUDIO
OUT
EXTERNAL
SPEAKER
AIR
SQUELCH
9VDC/
1Amp
+
50
300 GND 500 50
4 EXT WHIP 1 2 WHIP
MADE IN U.S.A.
/ 8 ON OFF
CAUTION:
BALANCED OUTPUT.
DO NOT GROUND.
BATTERY COMPARTMENT
10
1) EXT DC INPUT - Connect the AC Adaptor wall
transformer output cable to this connector. The SW8
requires 9 VDC power at approximately
1
Amp
current. With external DC power applied, the internal
batteries are not used.
2) ANTENNA 1 - This connector is used when
attaching receiving antennas with coaxial feed lines of
50 ohm nominal impedance. Accepts a standard
PL-259 plug. If selected by the ‘Shortwave Antenna
Select’ switch (Item 5), this input operates for the AM
Broadcast and Shortwave (100 kHz to 30 MHz) bands
only.
3) FM/AIR Antenna - This input is designed for either
an unbalanced 75 ohm input connection that is encoun-
tered with coaxial feeds, for example, or, for a two
terminal balanced antenna feed with 300 ohm nominal
impedance. Connect to the FM connection of a TV/FM
outdoor antenna feed (splitter), if available. Folded
dipoles or coaxial antennas will also provide good
results with this input for reception of the FM broad-
cast and Aircraft bands. Depending upon the particular
type of antenna feed, connect to one of the ‘FM/AIR’
terminals and the ‘GND’ terminal for an unbalanced 75
ohm input, or, connect to the two ‘300 ohm’ terminals
for a balanced 300 ohm input. If selected by the ‘FM/
AIR Antenna Select’ switch (Item 6), this input operates
for the FM broadcast (87-108 MHz) and the Aircraft
(118-137 MHz) bands only.
4) ANTENNA 2 - This connector can be used to
attach either a low impedance (50 ohm nominal) or
high impedance (500 ohm nominal) antenna. Use the
‘GND’ and ‘50 ohm’ terminals for a 50 ohm antenna;
use the ‘GND’ and ‘500 ohm’ terminals for a 500 ohm
antenna. If selected by the ‘Shortwave Antenna Select’
switch (Item 5), this input operates for the AM Broad-
cast and Shortwave (100 kHz to 30 MHz) bands only.
5) SHORTWAVE ANTENNA SELECT - This switch
selects one of three possible antennas to be used for
the 100 kHz to 30 MHz antenna input. The WHIP
antenna is built-in to the receiver and is located at the
upper left-hand corner of the receiver’s front panel.
‘ANTENNA
1
’ and ‘ANTENNA 2’ are described in
Items 2 and 4 on this page.
6) FM/AIR ANTENNA SELECT - This switch allows
selection of either the built-in WHIP antenna, or the
external 75 ohm antenna or 300 ohm antenna connect-
ed at the ‘FM/AIR’ terminals (Item 3) for the 87-108
MHz and 118-137 MHz frequency ranges.
7) LINE AUDIO OUT - This RCA connector provides
a constant low level audio source that is independent of
the front panel volume and tone control settings. It is
designed to interface to a tape recorder, CW/RTTY
demodulators, amplifiers, etc.
8) EXTERNAL SPEAKER - This connector accepts a
standard 1/4" diameter, 2-circuit, (monaural) phone
plug for connection of an external 4/8 ohm speaker.
DO NOT GROUND!
NOTE: Grounding of either speaker output wire will
limit maximum available audio output and damage the
SW8.
9) AIR SQUELCH - This control is operational only for
the Aircraft band. The control allows muting of the
receiver's audio when no signals are present. Adjust
the control until background noise just disappears
when no signal is being received.
10) MASTER POWER - This is a master power switch
which protects against accidental activation of front
panel power control. If the receiver is operated on
batteries and is not to be used for an extended period
of time, set this switch to the 'OFF' position. For
normal usage of on/off power control from the front
panel, set the 'MASTER POWER' switch to the 'ON'
position.
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