RE: VTTC grounding issues...

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Cameron B. Prince" <cplists@xxxxxxxxxxxxxxxxx>


Hi Brett,

> Steve, John, Cameron, and other tube coilers...
>
> I was wondering how you guys routed the ground in your
> VTTC secondary, tank circuit, and feedback/grid leak?
> Can I just use one low impendance cable which snakes
> around to every grounded area and then connects to my
> RF ground? (the same one I've used successfully on my
> meduim sized SGTC projects)

One unfortunate issue is, in my experience, if you are using a staccato
controller, you must combine RF ground with mains ground. So you are
correct, one common ground that ties everything together.

> I finished the wooden base for my VTTC today.  As soon
> as I glue on the feet and 3" flange for the top I will
> try and upload some pics.  I am using a modefied (I
> cut off some excess plastic so the 6" primary/feedback
> former could slide over) 3" PVC flange so I can leave
> the bottom of the secondary uncapped and it will
> pressure fit over the flange.  I can then quickly
> change out secondaries in the same system and try out
> coils with varying Fo in the future.  This leads me to
> another ground related question.  I was thinking of
> drilling a small opening  next to the base of the
> secondary to route the bottom end safely out of the
> upper tier of the base (my base is 2 level much like
> Steve Ward's single 833 base).  I should be safe from
> flashover since the voltage at the bottom of the
> secondary is at its lowest point.  Am I sound in my
> thinking here?

Yes, just don't run the lower end lead of the secondary inside the secondary
form. If you do need to do this, slide in and silicone a plastic baffle just
above the hole you drill. I burned up my v1 secondary due to arcing inside
the secondary form.

Good luck,
Cameron