[Prev][Next][Index][Thread]
First Coil - No Sparks
----------
From: djQuecke [SMTP:djQuecke-at-worldnet.att-dot-net]
Sent: Monday, June 08, 1998 8:07 PM
To: Tesla List
Subject: First Coil - No Sparks
I just completed my first coil yesterday but I'm not getting any discharge.
4.3" x 21.625" secondary - 22awg - 10 coats laq before winding then 15 more
coats. Ground via 10' flat braided cable to 10' of #4 stranded to 8' ground
rod.
Started with slight overcouple. Moved incrementally up to 1/4" above first
primary turn (no affect).
19"x4" toroid - Foil tape over foil over dryer duct and pizza pans. Tried
4" - 8" above final turn on secondary.
1/4" copper tube primary, spaced 1/4" 15 turns total - tried tap at several
spot on turns 14 and 15. 15 degree rise. Just over an inch between first
turn and secondary.
15kv 30ma NST
NST protection -
A 500ohm/65w resistor from each NST lead
1000pf ceramic caps across resistors
3.5mh coil on each leg (one coil showed "minor" shorting so I removed
both from circuit without affect)
Safety gap - across NST (actually more like two gaps, one from each leg to
ground)
I set gaps so they just barely didn't fire with NST alone. During runs, gap
would go off almost non-stop, I adjusted so that it didn't go off, no change
on output, readjusted so it goes off intermittently (once every 2 or 3
seconds)
Main gap - RQ static 6"x9x2" (8 gaps total) tested at 7 gaps in use)
Caps - 4 Oil filled poly each rated around 5300pf, 7500v, wired 2 pair in
series then the 2 pair are paralleled. Value tested at 5240pf on a decent
LC digital meter.
Power controlled by 10a variac.
There appears to be a great voltage increase if intensity of safety gap
discharge is a correct indicator. Main spark gap is firing and appears to
be doing what I expected.
All settings have resulted in zero output. I had hope to be ballpark close
and adjust from there but apparently, I'm not even on the field yet.
Thoughts?
Thanks,
dj