Selex LEMO to Peltor adapter

Parts

• LEMO FGG.1B.305.CLAD62
• NEXUS TJ-101
• Cable with 4 conductors. Suitable overall cable diameter is 4,7-5,3mm
  • https://partco.fi/tuote/datakaapeli-suojavaipalla-4x-0-25mm2-7349
• Original Selex PRR headset wire colors are:
  • Green Mic+
  • Yellow Speaker+
  • Blue Speaker-/GND
  • White Mic-/GND

Selex PRR LEMO to Peltor J11

Lemo pinout.The connections given are defined as 'when looking into the sockets'.[1]

LEMO

1. Microphone+ / Green
2. N/A
3. Speaker + / Yellow
4. GND / Brown (blue) (sprk)
5. GND / White (mic)

*Numbering clockwise from the back of the connector

JT-101 techincal documentation [2]

NEXUS TJ-101

Civil / Peltor wiring

1. Microphone GND / White
2. Microphone + / Green
3. Speaker + / Yellow
4. Speaker GND / Brown (blue)

Nato wiring

1. Microphone GND / White
2. Speaker + / Yellow
3. Microphone + / Green
4. Speaker GND / Brown (blue)

Suitable microphones

You must use a dynamic-to-electret microphone adapter circuit with a dynamic microphone. A quick Google search reveals that the Peltor MT7, MT73, and MT14 microphones require an adapter board. The Peltor MT53 is an electret microphone by default, so it won't need the adapter circuit.

Tested with Peltor MT7 microphone which needs the adapter circuit. MT53 series works without additional components.

• 

  Dynamic microphone to electret microphone input circuit [3]

  Partlist
  • R1 100 kΩ Resistor / 200-500 kΩ trimmeripotentiometri
  • C1 10µF Capasitator / MLCC size 0805 or 1206
  • Q1 BC547B Transistor / SOT-23 SMD

References

1. [1] https://www.cryptomuseum.com/radio/selex/prr/index.htm
2. [2] https://eu.mouser.com/datasheet/3/59/2/tj_101.pdf
3. [3] https://www.transkommunikation.ch/dateien/schaltungen/diverse_schaltungen/audio_circuits/Dynamic%20microphone%20to%20electret%20microphone%20input.pdf