Easy srsg's !

["sundog" <sundog-at-timeship-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

     Hi all!


I got some good news for everybody.

But firstly, thanks goes to Dave, of D&M's High Voltage.  He got me
the information that made me think of this neat little box.  He's
also helped me get up to 30" streamers from my little 4" coil.
Still a lot of work to be done on it, and I'm enjoyin' every minute
I work on it :)  It's still just plain' amazing to watch a bolt of
lightening wander about a toroid...Neat :)  Thanks Dave!

Mkay..The good stuff!  I've got easy plans for grinding the 1800
RPM sync motors.  The plans work, and the motors work like champs!
I've got a tiny little srsg, my testbed, that's seen abuse like
mad, and it's still runnin' beautiful.  I did some no-no's on the
rotary for the sake of testing (using a PVC disc..eeeek!), but it's
held up to several 2kva runs, so, till it blows up, it'll keep
runnin!

Now that the plans are done, I can finish up my work on the
pain-in-the-butt problem of phasing the thing.  My thoughts on this
(and how I did it!)

   Here's the skinny on it, and you'll laugh it's so simple.

 I'm using a quad nand gate, and feeding the input from a
photoxsistor into it.  Also being fed into the other side of the
gate is a diode/resistor feed from a 5v AC leg.  The nand gate sees
any voltage above 1.7v as a "high" logic level.  Once both inputs
go high, the output drops low (conducts), and the big red LED I
have on there lights up.  How's it work?  The diode\resistor from
the AC leg provides the mains signal to a gate.  The diode gives it
half-wave DC, and the resistor (still finding the perfect value),
clips the voltage to just over 1.7v at the peak of the 5v ac cycle.
The photoxsistor sits where your stationary electrodes would, and
recieve IR from an IR LED on the opposite side of the disc.  All
your electrodes are removed, btw (which is no big deal, if you're
constructing it, just phase it before you put 'em in, and mark the
shaft, disc, and case before disassembling for electrode
insertion!).  The peak of the mains comes around (30x a second),
and one gate is high.  The photoxistor gets an IR signal from the
LED at the same time, and *that* gate goes high.  Once both signals
are high (ac mains at peak, and electrode hole line up), your
status LED lights up.  Volia!  You're synced' to the mains.  Easy,
hunh?  I'll be scanning in my schematic as soon as I can get my
scanner up, and do a "final proof" of it.  It works, I know,
because that's how I phased my current gap.  I'm no EE here, just a
simple tinkerer, but this is a reliable way to do it.  I re-phased
the thing many times, and tried it on a variety of motors (1800 rpm
non salient, and others), and it *only* worked properly on the
salient pole sync motor.
  The pros, dirt cheap to build.  I think I spent around $10 on
parts, and I bought a lot of duplicates of stuff.  REliable.  I
think I have the only "erroneous" problem solved, I'll keep testing
that.  Easy...Just move the led& reciever around the edge of the
disc till it lights up.  That's where the electrodes are at the
peak of the mains.  The visible LED flashes 30x a second, so if
it's not in sync, or falls out of sync, you'll easily see the
change.  The LED seems to barely flicker when you're dead on, and
it gets choppier the further out of whack you get.

  I've tested this on the 1800 RPM gap, but I see no reason why it
won't work on the 3k-something rpm gaps.  The electrode hole will
still pass the same place 30x a second, and the photoxsistor should
be fast enough to catch it.  I'll post a parts list with the
schematic, or email me for what I'm using right now.

  Comments, suggestions, and ideas are gladly welcomed!  I just
wanted to put forward a new idea for a cheap method to phase the
gaps, without the need for an O scope or lots of time.  Or the risk
of burning up caps or a tranny.  So far, I've had 0% failure rate
with it.  It always got me fire on the rotary, with only minor
adjustment to hit the "sweet" spot.  Lemme know what you all think
of it!

  Just my $.02 again :)
                                                        Caio!
                                             Shad  AKA   Sundog