Re: Staccato coil operational- Thanks y'all

[FutureT-at-aol-dot-com (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

In a message dated 9/12/00 9:52:23 PM Pacific Daylight Time, tesla-at-pupman-dot-com 
writes:

> cwillis-at-guilford.edu 
>  
>  
>  Greetings Tube coilers, and thanks to Dave and John, etc. for helping me
>  come up to speed with my tube coiling.

Hi Carl,

Thanks for the update on your staccato coil.  Those super 
controllers would be most interesting to try.

That's really rotten about the new tube deal.  The guy is really a crook
then....there's no hope he'll ever send the tube?   Maybe a precise 
phase adjustment might help prevent the flashovers?

John Freau
--

>  
>  I just finished building a staccato controller for my coil per Dave
>  Sharpe's design, and it was working flawlessly on the first run:  "pop pop
>  pop pop..." The discharge makes a very satisfying sound and spark frequency
>  can be changed from 30 per sec to about 1 per sec.  I am using an SCR that
>  is rated at 600 VRRM and 25 A from Digi-Key that has the advantage of
>  having an isolated tab (so I can bolt it directly to a grounded enclosure
>  for heatsinking.)  I'm only using 9.5 Vcc for the timer circuit, although I
>  know that the timer works better at higher voltage.  I don't have a
>  regulator in the supply but I do have a 5000 microfarad electrolytic cap
>  and a bunch of other bypass caps that give a nearly ripple-free 9.5 volts
>  as far as I can tell with a pair of headphones (you make do with what you
>  have :>)
>  
>  Finding the right phase for the staccato triggering was pretty easy.
>  Although the coil will generate a small spark with either phase driving the
>  staccato (probably due to the charged up bypass capacitor) when the power
>  is increased the coil won't operate at all if the phase is wrong.  I have
>  both my staccato and my filament transformer on the same power cord, and if
>  the phase is wrong I just plug the cord in the other way around.  
>  
>  I still need to look at the operation on a 'scope and set the timing pot on
>  the 556 schmidt trigger properly.  But Dave is certainly right that this
>  timing control doesn't do a whole lot for the trigger.  I can turn the pot
>  from one end to the other and I still get nice staccato operation.   The
>  monostable timing pot gives from about 1 pulse per sec to 30.  I'd like to
>  try some potential ideas for a "super staccato" controller, including
>  converting the monostable timer into an astable timer, allowing the user to
>  adjust how many pulses in a "burst" and how many bursts per second.  Dave I
>  think is working on a "super staccato" controller that allows the user to
>  do this also but I'm not sure how he plans to effect it yet- let me know
>  what you figure out, Dave! 
>  
>  My present 833A is an older one and so I still have the occasional problem
>  with a flashover.  Unfortunately the fella I just ordered a new one from
>  ran with my money and won't send the tube...maddening!
>  
>  -Carl