Monophone modification for JUMA  06.10.2006 OH7SV

Open the monophone case by removing the three screws

Picture 1. Original connection inside the monophone

Modifications inside the monophone
1. Remove the 2k7 resistor (red, viol, red) by cutting the resistor wires
2. Remove diode by cutting the wires
3. Desolder the shield wire from the board and resolder it to the mic GND (large hole near mic). Use some additonal wire.
4. Desolder the red wire from the board and resolder it to the hole/pad going to the PTT switch (this was originally the shield wire pad)

Picture 2. Modifications done inside the monophone

Close the mic case
Obs 1. Place the mic gasket properly in to the correct position
Obs 2. Place the the PTT handle and observe the rubber pad between the handle and the switch

Modification to the plug
1. Cut the mic cable near to the original two end plug
2. Prepare the wires for soldering, black wire is not used, cut it out
3. Solder as follows: White - tip, Red - mid, Shield - GND

Picture 3. The wires prepared for soldering to the plug


Picture 4. Completed microphone in operation