[Amps] Grid Metering

[KBØNLY]

Now that i have my amp up and running i find one thing really odd about its operation, but this may be normal i don't know as i have to wait for a reply from Ian GM3SEK who i got the Triode Board from which includes the metering circuits as well.

When i key the amp, no drive, i get about 100mA of plate idle current, from what i read online this should be fine using the GI7B triode.  But the Grid current meter goes slightly negative, it pushes the needle just a smidge below the zero mark, and then when i apply drive the Grid meter moves lightning fast on voice peaks, i mean you can hear the meter going tickety tickety tickety, etc.

The Plate current meter seems to follow fine.  I had to hook up all the old CW key i keep up on the shelf and with a keydown, short and with pauses to cool etc, i tuned up the amp and everything seemed to work just fine.  Go back to SSB and again its fine, i just thought it was odd how that Grid meter swings slightly negative with no drive and then seems to work ok but super fast in response when drive is applied.

I adjusted my input network a smidge more and basically fine tuned everything over and over to make sure i didn't miss a thing.  I'm now seeing just a needle width under 500W with 20W of drive, Plate current comes up to about 400-425mA on voice peaks and the Grid current gets to about 80-90mA.

Anyway, thought maybe someone could tell me why the meter does that little negative swing?  I checked and rechecked the components on the board an everything seems fine.

73,

Scott KBØNLY