Type RS 38-A Carbon Microphone

© Brooke Clarke 2012

Type RS 38-A Carbon
          Microphone
Background
Description
Related
Links

Background

This is a World War II vintage carbon microphone.  It has a patented Push To Talk - Twist to Lock button.

Description

The 1/4" Phone Plug Ring is connected to the carbon microphone case.
The 1/4" Phone Plug Sleeve is connected to the carbon microphone center terminal.
The 1/4" Phone Plug Tip is connected to the Push To Talk switch terminal which gets shorted to the sleeve when pressed.
This is a poor design in that the mike is always connected to the Sleeve and Ring and so could be used for eavesdropping.

The resistance of the mike varies between 2k and 12k, not sure if it's good or bad?

Type RS 38-A Carbon Microphone Type RS 38-A Carbon Microphone
Type RS
                38-A Carbon Microphone patent 2066022
Type RS 38-A Carbon Microphone Sleeve, Ring, Tip


2066022 Thumb Switch, W.T. Weidenman, Dec 29 1936, 200/6BB ; 200/17R; 379/421; 379/422 -
H413H Microphone output-level tester, Arthur S. Lelie, Navy, 1988-01-05, - looks like the RS 38-A carbon mike

Related

Audio Connectors & Military Cloning - Fill - Retransmission
HP 204B Audio Oscillator from HP 3350 Carrier Test Set (AN/USM-181 Telephone Test Set
HP 241A Audio Oscillator w/Radio Buttons
Military Audio Accessories
Audio Patch Panel
TS-585 Audio Level Meter
U-229 Audio Accessories
U-229 Pin Out by Function

Links

Brooke's PRC68, Products for Sale, Military Information, Electronics Page page created May 29, 2012.