YAESU MH-59 Mic RFI NIGHTMARES!

[TonyV225]

I had the RFI problem when I frst bought the Microphone when I first tried it but was trying it on a my 857D portable setup while down south hose and dog sitting here in Wisconsin. I finally as I said pulled the Mic back out a week or so agon and hooked it up to my FT-897 and it worked great so I dug out my FT-857D and retried that setu and it worked great and Im still running it everyday since.

I think what hapened on my first initial try was I was on the second floor of a big old mansion and had a G5RV Inverted V coming off the uper ppart of a balcony about 4-6 feet behind a wall fro where my radio setu was sitting so in return I was getting the RF feedback. The next time I head back down that way Im going to try again but also bring a snap on Ferrite beed if the problem is again there with that particular setup.

All I know is its working flawless here which makes me feel better knowing the Microphone wasnt a complete and utter waste of money and if anyone has one they would like to sell reasonably (seeings how it is only usable at home here) Ide like to buy another for my FT-897D.

 

[EMAN]

Locate inductor L1007 next to the microphone cable connector inside the
Yaesu MH-59 microphone. Note one end of the inductor goes to the foil
ground of the microphone PCB. The other end of that inductor goes under the
PCB cable connector to pin #2 which is the mic cable ground. Solder a small
jumper across L1007. This grounds the mic cable ground wire to the foil
ground of the Mh-59's PCB. This is the fix I did to my MH-59. I can lay my
mic across the coax in TX with no RF with the antenna within 8 feet and
the FT-857 at full power output. This is a simple fix and requires no ferrites
at all.

 

[RubberDuck01]

thx 4 information, if it happened again I will try your fix

 

[Happy_Hamer]

Can you take some high def close up pictures?

Locate inductor L1007 next to the microphone cable connector inside the
Yaesu MH-59 microphone. Note one end of the inductor goes to the foil
ground of the microphone PCB. The other end of that inductor goes under the
PCB cable connector to pin #2 which is the mic cable ground. Solder a small
jumper across L1007. This grounds the mic cable ground wire to the foil
ground of the Mh-59's PCB. This is the fix I did to my MH-59. I can lay my
mic across the coax in TX with no RF with the antenna within 8 feet and
the FT-857 at full power output. This is a simple fix and requires no ferrites
at all.

 

[EMAN]

Sorry I have no camera. But I did use this photo to show L1007's location.

 

[EMAN]

This may be a little more helpful. It shows the microphone cable's PCB
connector and inductors 1-8. (Notice inductors 6, 7 and 8's configuration.)
This view is with the mic cable unplugged, top of mic to right, encoder to
top right and PTT to bottom right.

 

[19CQ35]

This seems to solve my problem as well.

Thanks for posting your soluition.