Tape Recorder Output on LEF Master Station

Updated on December 21st, 2025

Modification

Tape recorder output on LEF master station allowing conversation from both sides to be recorded.

 
This modification provides a 10K Ω output to a separate device. Make sure external device has 10K Ω audio input.

Difficulty Level

5 – Hard – circuit creation and internal addition.

Components Required

  1. Resistors:
    • Two 10K Ω, 0.25 W
    • One 10~15K variable resistor
  2. Capacitor:
    • Two Aiphone model NP-25V (33 µfd, 25V, non-polarized)

Instructions

  1. Install components as shown on the following schematic.
  2. This modification will allow a tape recorder to record both sides of the conversation while the master is communicating with another station.

 

LEF-3

 
Add components as shown above, connected from pin 6 of IC2. Connect GND of input to recorder to E of LEF Series master station.

 

LEF-5

 
Add components as shown above, connected from pin 6 of IC2. Connect GND of input to recorder to E of LEF Series master station.

 

LEF-10

 
Add components as shown above, connected from pin 6 of IC2. Connect GND of input to recorder to E of LEF Series master station.