[Elecraft] KAT-500 Unreliable Tuning

[Dennis Moore]

I checked inside my tuner, I only have one green wire instead of two. 
Serial #2120.

I also have the issue of erratic tuning when applying power, adding an 
additional common mode choke helped calm things down.

Dennis NJ6G

On 3/8/2021 09:07, Rajiv Dewan wrote:
> I had a similar issue with my KAT500.  I opened it up and the problem was obvious: there are two green 12g wire bridges that cross. (You can see them in this image: (kat500_inside_500_530x at 2x.jpg  <https://cdn.shopify.com/s/files/1/2029/4979/products/kat500_inside_500_530x@2x.jpg?v=1536760566>. You can see one end of the longer green wire near the big red toroid.) There had been arcing between them.  My guess is that they arced at higher power levels. I replaced them with slightly longer wires and bent them to create more clearance.  That solved my problem.
>
> I recommend taking taking the cover off and taking a look.  The problem may be obvious as it was for me.
>
> Raj, N2RD