- 4 -
IGNITION NOISE INTERFERENCE
With weak signals, you may experience interference of the signal by background
noise. This radio has NB and ANL circuits which will help reduce background noise
from sources such as your ignition system. However, background electrical noise may
come from several sources and all noise may not be eliminated. With extremely weak
signals, you can operate this radio with the engine turned off, which should improve
reception. If the ignition noise level is too high to allow proper operation under most
conditions, you should have your installation of the radio checked by a qualified
technician.
ANTENNA
This radio has a jack in the rear for a standard PL-259 antenna plug. If you are
looking for the most range for your transmission, use a vertically polarized, quarter-
wave length antenna. If antenna height is a problem, you may use a shorter, loaded-type
whip antenna although you can expect some loss of transmission range.
To improve performance, your antenna should be matched to your radio. Your antenna
can be adjusted so that it matches your radio.
EXTERNAL SPEAKER
The external speaker jack (EXT SP.) on the rear panel is used for remote receiver
monitoring. The external speaker should have 8 ohms impedance and be able to handle
at least 4 watts. When the external speaker is plugged in, the internal speaker is
disconnected.
PUBLIC ADDRESS
To use the Public Address (PA) function, first connect an external speaker to the PA.
SP. Jack on the rear of the radio. See the above specifications for a proper external
speaker. Keep the speaker away from the microphone to avoid acoustic feedback.
- 5 -
CHAPTER 3 OPERATION
CONTROL FUNCTIONS
FRONT PANEL
1. MICROPHONE
JACK:
Used to connect microphone for voice source.
2. ON/OFF VOLUME CONTROL:
This knob controls the volume and power to the
radio. To turn radio on, rotate the knob clockwise. Turning the knob further will
increase the volume of the receiver.
3. SQUELCH
CONTROL:
This knob is used to eliminate background noise being
heard through the receiver, which can be disturbing when no transmissions are
being heard through the receiver. To use this feature, turn the knob fully
counterclockwise and then turn clockwise slowly until the background noise is just
eliminated. Further clockwise rotation will increase the threshold level which a
signal must overcome in order to be heard. Only strong signals will be heard at a
maximum clockwise setting.
4. MIC GAIN CONTROL:
Adjusts the microphone gain in transmit and PA modes.
This controls the gain to the extent that full talk power is available several inches
away from the microphone. In the Public Address (PA) mode, the control functions
as the volume control.
19
EC H O
O FF
EC H O TIM E
VO L SQ
M IC
M IC G AIN RF G AIN
2
1
O FF
3 4 5 6
11
6 0
4 0
M O D
PW R
6
3
1
1.5
2
20
0
SW R
1
S
5
7
3
+6
0
10 0
%
M
A
X
12
9
15
3
+4
0
+20
9
8 0
dB
10
M O D
E
D
TB PW R
A
B
TB
O FF
C
H
G
F
12 13 14
AM
BRIG H T
N B/AN L
SW R
O FF
N B/AN L
FM
PW R
PA
D IM
M ED
17
+10KH z
16
15
18
7
8
9
21
20
22
