Re: new secondary
In a message dated 99-07-02 12:44:20 EDT, you write:
> I introduced myself a while back and now it's time to fess up. I've been
> playing but not reporting on progress. I have got some pictures to put on my
> website "real soon now". I'm nearly ready to jag in my 10Kv 28ma OBIT and
> try my 12Kv 60ma neon. I've gotten solid discharge sparks up to about 8.5
> inches and spay type sparks up to about a foot or so. I don't know if that's
> good for an OBIT or not, I'm using salt water caps so far.
Considering the salt watter caps, i think 8.5" is good. I obtained
13" sparks from a 10kV, 23ma OBIT, using a .0015uF mica cap,
and static gaps. In one test, I used a .0066uF cap and a sync
rotary with the same
OBIT, and obtained 25" sparks, but the OBIT quickly destroyed
itself from the resonant build-up.
> I made my first secondary on a 4 inch piece of clear Plexiglas tube and
> coated it with spay acrylic varnish. It seems to work OK but I wonder if the
> clear acrylic spay was as good as any to use? It looks fine.
> My main reason for a message right now is this:
> I had some 22 gauge magnet wire left on the spool and decided to wind
> another secondary on a piece of 6.25 inch OD PVC drain pipe. I was shooting
> for the magic 24 inches but ran out of wire at 22 and one half inches of
> coil. Is a 24 incher really preferred or would a 22.5 work just as well. I
> want to decide now before I go any further with it. I've got a lathe setup
> now so winding takes no time at all.
A good reason to go for the full 24" or even longer, is to prevent end
to end to end breakdown or turn to turn breakdown, if you eventually
increase the power input greatly. I'm using a 6.5" by 23" secondary,
now, and I've gotten up to 65" sparks with it but it's on the edge of
breakdown at that point. I'm using #28 wire. The same thing happens
(occasional racing sparks at high power) using my 4" by 23" secondary
which also uses #28 wire.
You can extend the wire by soldering on another length of wire. Just
make the solder joint smooth and flat.
> Any and all suggestions appreciated.
> -Joemac >>