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Eliminating Call Tone from Sub Station at LEF Master Station

Updated on December 21st, 2025

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Modification

Eliminate incoming call tone from sub station at a master station.

Difficulty Level

3 – Moderate – removal or replacement of internal components.

Components Required

N/A

Instructions

LEF-3/3C: remove transistor TR7.
LEF-5/5C: remove transistor TR7.
LEF-10/10S: remove transistor TR8.
LEF-10C: remove transistor T7.

LEF-3

LEF-5

LEF-10

All Call to Standard LE Series Sub Stations Eliminating Call Tone from Sub Station at LEF Master Station Increase timing circuit of call-in LED Installing Volume Control on LE Series Sub Station LED Monitoring Indicator on an LE Series Sub Station Separate Transmit and Receive Volume Controls on LEF Series Master Station Tape Recorder Output on LEF Master Station Using Relay Contacts with the LEF Series