skewed evelope

[W1RKW]

I'm tinkering with a solid state PW AM rig and I've got output but the envelope is skewed. see picture.  What typically causes this anomoly? Sorry for the poor artwork.

A little info on the rig.  It's a single MRF type transistor in a class C config.  Modulator is a 70v line transformer with the laminations reconfigured and it's driven by an audio amp in reverse.

I'm wondering if it's a biasing issue.

With the exception of skew in the envelope, 100% modulation is obtainable and it looks clean and sounds ok on a receiver too.

[WBear2GCR]

Your drawing shows a differential in time between the upper and lower "traces".
But how are you actually measuring this?

It is possible that the issue is in your 'scope, not in the signal, assuming some sort of dual trace scope, there may be an anomaly in the way it is set up that is causing it to look incorrect.

       _-_-WBear2GCR

[W1RKW]

I thought about that too so I tried looking at the envelope on my FT102 and all looks OK there.  I'm not sure why the bottom half of the envelope is shifted nearly 90 degrees from the upper half of the envelope on the little PW SS rig.

[WA1GFZ]

It could be the final DC bypass cap setting up a delay

[W1RKW]

Found it.  Another ground issue in my shack.