N1GY- The simple Approach to Ham Radio
An Adapter to Connect W2ENY headsets to Yaesu Mobile Radios Like the FT-7800R, 7900R, 8800R and 8900R
This circuit works very well and will adapt most computer headsets to the Yaesu FT-7800R,
FT-7900R, FT8800R, and FT-8900R. It should also work on any Yaesu Radio that uses the MH-48 hand microphone. The 22K resistor in the PTT line is necessary to let the radio know it is a PTT signal and not something from the DTMF pad or the specialized buttons on the mic. Obviously this adapter makes no provision for DTMF or the other specialized buttons of the hand mic.
In building this adapter, I was able to get both of the resistors and the capacitor to fit under heat shrink tubing and thus make it appear similar to the adapter that Bob sells along with the headset. In my particular installation, the adapters are out of sight behind the operating desk and only the "Radio Selector" that the headset plugs into is visible on the desk surface
I recently purchased a headset from W2ENY, Bob Langston up in New York for use with my Icom IC-706MkIIG. It works great once I solved a few wiring issues on my end of things. Unfortunately, I also wanted to use the headset with my Yaesu FT-7800R and Bob informed me that he does not make an adapter for that radio or its class mates as listed in the title above.
I have been building adapters for this class of radios for years and they always worked well with the headsets I used. My previous headsets are very different that the one that Bob supplies but their basic original purpose as computer headsets was the same. I figured I would give it a go and see if my adapter, slightly modified to the same type interface as the ones Bob makes, would work with his headset.
The circuit diagram below needs little in the way of explanation as it is covered fairly well on another page on this site. The main difference is the connection or interface between the headset and the adapter. Because of a slight but important difference in the wiring of the headset there are a few differences in this adapter as opposed to the one featured elsewhere on this site. The main changes are that the jacks are in-line rather than panel mount and the wiring for the mic jack is slightly different than my other adapters because of a difference in the way that the headset mic is wired to it's stereo plug. Specifically, there is no connection at all to the ring of the stereo plug. The mic is wired to the tip and to the shaft only. The jacks that the pic plug connects to must also be wired this way or they will short out the audio. Bob's adapter also has provision for the mic and the PTT only. He suggests that the earphone plug on the headset be plugged directly into the "phones" jack on the radio. Because I use a mic selector between the headset and the radio, I was unable to do this, so an extension was added to bring the earphone jack out to the same place as the mic and PTT jacks.
Once that was accomplished, I added a "radio selector" which is pictured on a different page here on the site. The main point here is the adapter that allows Bob's excellent headsets to be connected to a certain class of radios.