Yaesu MH-31 MicrophoneEarlier this week, I was chatting with Field Radio group member Peter VK3YE on Facebook. I had spoken with Peter earlier that day when he called me during my Yalgorup National Park WWFF activation on 40 metres and he mentioned something that I thought I would share with those of you in the group who are using the Yaesu FT817 model.

Apparently the standard microphone that comes with the rig leaves a lot to be desired.

I know there are many members who are using this model which has a maximum output power of 5 watts QRP, so I am certain that you will find what Peter had to say and what you can do about it of interest. Apparently the dynamic MH-31 microphone that comes with the FT817 is not a very good performer and there is a simple mod that you can do, using an electret condenser microphone element instead.

Let’s face it, when you’re operating QRP, you are more vulnerable to any weaknesses with your equipment and you can’t afford to have any element of your rig or antenna let you down. This mod might be the difference between getting that rare DX or missing out, so I suggest checking it out!

Peter has put together an excellent You Tube video that is just under 7 minutes in length, accessible on the left where he explains the mod and its benefits.
He also does a comparison testing it side by side with another exact same model.

Peter is well known in VK for his pedestrian mobile and portable operations and is a keen builder and experimenter of antennas and other equipment. I have read a number of articles he has contributed over the years to the monthly Wireless Institute of Australia (WIA) Amateur Radio magazine and he also has a busy You Tube channel with over 300 videos. These videos are highly informative and well worth a look.

During the video, Peter references John M0UKD’s excellent website and an article he added in early 2015 which you can access here. In this article John provides easy to follow instructions step by step of the process of doing this mod and includes a number of good sized photographs of the process.

I use a Yaesu FT857D transceiver which came equipped with the same model of microphone and I operate using QRP from time to time so I should probably check this out also :-) .