I needed to split the audio from my R-392 to feed two different RTTY  TU's as well as monitor the input audio and I want to be able to reset the audio levels as needed.  The "Box" with the U77/U connector  will come in handy. I also installed  3.5MM (1/8 inch jack) for my recorder and or amplified speaker. The meter plugs in as I am running short of small 50-100 uA meters. The toggle switch is dedicated to  PTT when transmitting FSK.
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