My Kenwood TS-440 bites when keyed

[Tallman]

I have not been on the air for some time. I went upstairs to fix up an amplifier for somebody on this forum.
Well since I was sitting there working I turned the Kenwood on and hopped around the bands and found 14.265 busy so I stopped and listened. There was a lull and I keyed up to see if I could reach them. When I keyed up I felt a tingle in my hand. What The Florida? My station grounds are good and the radio is connected to the antenna through a 1:1 balun. I am puzzled. Any one encounter this before?

 

[jon666]

only when i had a bad ground it bit my lips lol

 

[DainBramage]

end fed antenna?

 

[BJ radionut]

MC-60 mic?

 

[Tallman]

end fed antenna?

Does it on resistor load too.

 

[Captain Kilowatt]

Does it on resistor load too.

That's not good. RF will do that but not into a dummy load. Check between the chassis and the AC ground. You may have a hot chassis and you want to solve that issue for sure.

 

[Tallman]

That's not good. RF will do that but not into a dummy load. Check between the chassis and the AC ground. You may have a hot chassis and you want to solve that issue for sure.

So many jokes I am passing right now. Since I asked for help I'll refrain.

 

[nomadradio]

Open ground on a coax connector?

73

 

[wavrider]

If you have a different power supply try it.

 

[jon666]

i was not joking just trying to help

 

[nomadradio]

The RF output of the radio should be traveling along the inside surface of the coax shield. The 'bite' tells you that there is RF current on the outside of the shield. Short version of the explanation is that the coax has become an element of your antenna system, in addition to being the feedline. This is never a good thing.

There is more than one way for this to happen with the antenna attached. But if it does this on the dummy load, you have a bad coax jumper.

Period.

73

 

[Tallman]

i was not joking just trying to help

No problem. I was resisting the urge to crack wise. "Hot chassis, that's what she said."

 

[Captain Kilowatt]

Yeah my comment about the hot chassis wouldn't hold up if it only happens when he keys up. It would be there all the time. It's amazing what can be learned by going back and reading things again. LOL

 

[BJ radionut]

MC-60 mic?

http://ke6i.com/mc60a.html

http://lists.contesting.com/_rfi/2001-01/msg00038.html

https://pa8e.nl/kenwood-mc-60-microphone-rfi-solution/

http://www.qth.net/pipermail/kenwood/2005-April/012024.html

And the Lists goes on and on and on, about RFI issues on that mic
(some MC-50's also)...That's why I made the comment...
All the Best
Gary

 

[Tallman]

http://ke6i.com/mc60a.html

http://lists.contesting.com/_rfi/2001-01/msg00038.html

https://pa8e.nl/kenwood-mc-60-microphone-rfi-solution/

http://www.qth.net/pipermail/kenwood/2005-April/012024.html

And the Lists goes on and on and on, about RFI issues on that mic
(some MC-50's also)...That's why I made the comment...
All the Best
Gary

I just have the hand mike but there must be some common issues.
Thanks for the tips!
Dennis