Galaxy DX 949, Service Manual

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The receiver and transmitter are controlled by the push-to-talk switch on the microphone. Press the 
switch and the transmitter is activated, release switch to receive. When transmitting, hold the 
microphone two inches from the mouth and speak clearly in a normal voice. The radio comes 
complete with low impedance (500 ohm) dynamic microphone. For installation instructions of the 
microphone, see section “ALTERNATE MICROPHONES AND INSTALLATION”.

2.3 OPERATION

2.3.1 PROCEDURE TO RECEIVE

1. Be sure that  power source,  microphone and antenna are connected to the proper connectors 
before going to the next step. 
 
2. Turn unit on by running 

VOL

 knob clockwise on transceiver. 

 
3. Set the 

VOL

 to a comfortable listening level. 

 
4. Set the 

MODE

 switch to the desired mode.   

 
5. Listen  to the  background  noise  from the speaker. Turn the 

SQ

 knob slowly clockwise until the 

noise just disappears. Leave the control at this setting. This 

SQ

 is now properly adjusted. The 

receiver will remain quiet until a signal is actually received. Do not  advance the control too far or 
some of weaker signals will  not  be heard. 
 
6. Set the 

CHANNEL 

selector switch to the desired channel. 

 
7. Set the 

RF 

gain control fully clockwise for maximum receive gain. 

2.3.2 PROCEDURE  TO  TRANSMIT

1. Select the desired channel of transmission 
 
2.  Set the 

MIC GAIN

 control fully clockwise. 

 
3. If the channel is clear, depress the push-to-talk switch on the microphone and speak in a normal 
voice. 
 

2.4 ALTERNATE MICROPHONES AND INSTALLATION 

 
For best results, the user should select a low impedance dynamic type microphone or a 
transistorized microphone. Transistorized type microphones have a low output impedance 
characteristic. The microphones must be provided with a four-lead cable. The audio conductor and 
its shielded lead comprise two of the leads. The third lead is for transmit control and the fourth is 
for receive control. The microphone should provide the functions shown in schematic below 
(Figure 2-3).  
 
 
 
 

4 WIRE MIC CABLE