Speaker/Microphone for Yaesu FT-817

[AC7WL]

Hello folks,

     Not sure whether to throw this in homebrew or QRP but here goes.  I just purchased a Pryme SPM-100 speaker/mic with the intention of adapting it to my FT-817, which I love a great deal but wish it had come with a speaker/mic vice the microphone only (makes it hard to hear while it is in the bag for portable operation).  I am purchasing a couple of female adaptors (for the plugs on the connector) and will be bending a steel plate and securing it where the stock strap is supposed to go (I never use it...) on the right hand side of the case.  I have the RJ-45 crimper, cable, and other associated hardware but a few questions before I jump in...  If I connect the speaker out jack from the radio to the mic with a jumper (not the mic connector but speaker connector on the jack), would I have to add anything between the two (resistor/potentiometer) or could I just leave the switch on the rig in the speaker position and use it as is?  The microphone input connection is a simple one and the pinouts in the manual are pretty self-explanatory...  Would my audio suffer, or, does the quality of the audio from the Pryme SPM-100 compare negatively with the stock microphone?  Guess there is no better way to find out than to give it a go but wanted a few pointers prior to.

 

[KD7BCY]

You might need to hack up the speaker-mic to get it to work. I don't know what the 817 will think of the HT-type PTT which is hooked up to the mic element. The 817 has direct connections to the PTT switch and mic element. I can't remember the exact hookup of the HT speaker-mics, but I think it puts the PTT switch inline with the mic and circuitry, so if you seperate them and plug it into the RJ jack, it should work fine.

I built an adapter to use an aircraft headset with my 817, just needed to put in a PTT switch and a resistor and capacitor, the most basic mic driver circuit I could find. Might not be perfect, but it works. The headphones go directly to the speaker jack and I used half of an ethernet cable for the PTT and mic. I have pictures at my web site:

http://home.teleport.com/~kd7bcy/adapter.html

As for audio quality, I would assume that hooking up a speaker-mic is more for convenience than quality, but I don't think there would be any problems once everything is setup and the mic gain set(a setting I haven't tested with my headset yet beyond a few on-the-air checks, I need to dig out my test equipment and see what the output looks like, but people haven't seen much difference between the settings so I usually leave it on the default 50)