![background image](http://html1.mh-extra.com/html/cobra/148gtl-dx/148gtl-dx_instruction-manual_2630887019.webp)
ALTERNATE MICROPHONES AND INSTALLATION
For best results, the user should select a low-impedance dynamie type micro
phone or a transistorized microphone. Transistorized type microphones hâve a
low output impédance characteristic. The microphones must be provided with a
five-lead cable. The audio conductor and its shielded lead comprise two of the
leads. The third lead is for receive control, the forth is for grounding and fifth is
for transmit control.
The microphone should provide the fonctions shown in schematic below.
4WIREMIC CABLE
Pin Number
1
2
3
4
Mic Cable Lead
Audio Shield
Audio Lead
Transmit Control
Receive Control
If the microphone to be used is provided with pre-cut leads, they must be revised
as follows.
1. Cut leads so that they extend 7/16” beyond the plastic insulating jacket of
the microphone cable.
2. Ail leads shoudl be cut to the same length. Strip the ends of each wire 1/8"
and tin the exposed wire.
Before begining the aefoal wiring réad carefolly, the circuit and wiring infor
mation provided with the microphone you select. Use the minimum head re-
quired in soldering the connections. Keep the exposed wire. lengths to a mini
mum to avoid shorting when the microphone plug is reassembled.
-
1 8
-
Summary of Contents for 148GTL-DX
Page 32: ...со SO AOJ VR2 BLOCK DI AGRAM ...
Page 33: ...SCHEMATIC DIAGRAM ...
Page 41: ...Parts Layout Top View Î37 2SB525C 1 4 1 5 ...
Page 42: ...PARTS LAYOUT Top View ...
Page 43: ...ADDED PARTS MAIN PCB Bottom View PC 879AB ...
Page 44: ...COPPER PATTERN SWR PCB CH SW PCB LED PCB CD ...
Page 48: ...го w INTERNAL DIAGRAM IC s MB87I9 ...
Page 49: ...INTERNAL DIAGRAM IC s го А ...
Page 50: ...INTERNAL DIAGRAM IC s S 0 4 2 P 25 ...
Page 58: ...со го BLOCK DI AGRAM ...
Page 59: ...PB OIO SCHEMATIC DIAGRAM ...
Page 60: ...WiRING DIAGRAM 3 5 3 6 P C 881 P C 8 8 0 ...
Page 66: ...COPPER PATTERN MAIN PCB ...
Page 68: ...P B O I O ADDED PARTS MAIN PCB H fs il 8 46 ...
Page 70: ...COPPER PATTERN SUB ASSY PCB s ...
Page 71: ...PARTS LAYOUT MIC JACK 49 ...
Page 74: ...INTERNAL DIAGRAM IC s MC14008B 1 4 Cou l 13 S 4 13 S 3 11 S2 10 S 1 16 15 14 13 12 11 10 9 52 ...
Page 75: ...сл С О INTERNAL DIAGRAM IC s OSC out Г 2 out FS PO PI P2 P3 PA P5 P6 P7 P8 MC145106 ...
Page 76: ...INTERNAL DIAGRAM IC s 14 0UT4 13 I N 4 12 lN 4 11 VEE 10 IN 3 9 I N 3 8 0UT3 TA75902P 54 ...