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ALTERNATE MICROPHONES AND INSTALLATION 

Before beginning the actual wiring, read carefully the circuit and wiring information 

provided with the microphone you select. Use the minimum heat required in soldering 
the connections. Keep the exposed wire lengths to a minimum to avoid shorting when 
the microphone plug is reassembled. 

 

For best results, the user should select a low-impedance dynamic type microphone or 

a transistorized microphone. Transistorized type microphones have low output 
impedance characteristics. 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 fourth is for receiving control.  

 

 

 
The microphone should provide the functions shown in the schematic below. 
 
 

4 WIRE MIC CABLE 

 

Pin Number 

Mic Cable Lead 

1

Audio 

Shield

2

Audio Lead

3

Transmit 

Control 

 

4

Receive 

Control

 

 

 

 

 

 

 

 
 

 

 

Fig. 2

 Microphone plug wiring 

 
 
 

 

To wire the microphone cable to the plug provided, proceed as follows : 

 

 

Fig. 1

 Your transceiver microphone schematic. 

1.  Remove the retaining screw. 

 

 

 

2.  Unscrew the housing from the pin receptacle body. 

If the microphone to be used is provided with pre-cut leads, they must be revised as 

follows. 

 
3.  Loosen the two cable clamp retainer screws. 

 

 

1.  Cut leads so that they extend 7/16" beyond the plastic insulating jacket of the 

microphone cable. 

4.  Feed the microphone cable through the housing, knurled ring and washer as shown 

Figure 2. 

 
2.  All leads should be cut to the same length. Strip the ends of each wire 1/8" and tin 

the exposed wire. 

 

 

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Summary of Contents for DX 48T

Page 1: ...TENTS PAGE CHAPTER 1 Specifications 2 CHAPTER 2 Installation 3 Installing The Radio 3 Ignition Noise Interference 4 Antenna 4 External Speaker 4 Public Address 4 CHAPTER 3 Operation 5 Front Panel 5 Re...

Page 2: ...installed Make sure nothing will interfere with either the radio or the mounting bolts Mark and then drill holes for the mounting bracket 2 Most radio antennas come equipped with a PL 259 plug Connect...

Page 3: ...S 1 MICROPHONE JACK Used to connect microphone for voice source 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 specifi...

Page 4: ...allows the user to monitor signal strength RF output power SWR level and AM modulation level 22 RX TX LED The red LED indicates the unit is in the transmit mode The green LED indicates the unit is in...

Page 5: ...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 the weaker signals will not be heard 1 ANTENNA This jack ac...

Page 6: ...and fourth is for receiving control The microphone should provide the functions shown in the schematic below 4 WIRE MIC CABLE Pin Number Mic Cable Lead 1 Audio Shield 2 Audio Lead 3 Transmit Control 4...

Page 7: ...ure 2 are pushed back onto the microphone cable before starting to solder If the washer is not captive to the pin receptacle body make sure that it is placed on the threaded portion of the pin recepta...

Page 8: ...Please include a note with a detailed description of the symptoms This is important because it will help the technician who works on your radio to locate your problem Intermittent problems are easily...

Page 9: ...Printed in Taiwan AT0949011D...

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