Zero Crossing Strobe & possible kits?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Colin Dancer by way of Terry Fritz <twftesla-at-qwest-dot-net>" <CMD-at-dataconnection-dot-com>

Hi Daniel et al,

The replacement part is an Atmel T2117, which just came onto the market late
1Q this year.  It will need a couple of resistors and a diode, but performs
the same function as the CA3059, and should reach general availability later
this year. For details see
http://www.atmel-wm-dot-com/upload/doc3a07f81ad7ab3.pdf, in particular the "Fig
10. power switch" circuit which is very similar to the circuit needed for
our application, except that we need to drop the photo-diode and tweak the
resistors so it is always on.  

The chips aren't yet available from any major suppliers, but I've ordered in
bulk from the manufacturer and our US office have just received a shipment
of 20 parts.  If you want one let me know, and I'll send it out once I've
proved the component works in our application.  The chips have cost me about
$1.20 each including shipping here, so I'm willing to send out a small
number for free to help fellow SRSG users.

Personally I don't have any spare CA3059's, but I believe Nick Fields (who
posted my circuit to the list) might have one or two.  As he says in a
previous email they are still available from obsolete component suppliers
but at $10+ each with the price going up.

Finally, if people are interested in a kit I could probably stretch to
making a few circuit boards and collecting together the required components
for US and UK usage.  I'd have to look into the details, but I'd guess price
would be about ?10-?15 a piece including circuit board and all the
components (excluding case and lead).  In terms of postage, however, it
would probably make more sense for someone in the US to collect the bits for
the US kits.  

Lets get a feel for interest first.

Cheers,

Colin.

P.S. Not trying to boast, but if you haven't seen one of these units in
operation they are amazing :-)  My 6" x 3000 rpm SRSG seems to be dead still
under this unit with zero jitter.  I've even taped a scale round the
periphery and can directly read off the firing angle.

-----Original Message-----
From: Daniel Hess [mailto:dhess1-at-us.ibm-dot-com]
Sent: 07 May 2002 22:09
To: Colin Dancer
Subject: RE: Zero Crossing Strobe


Collin

What is the replacement part number? As I recall you had some of the
original CA3059's for sale. What is your asking price and what are your
terms?

Thank you,

Daniel Hess
---------------------- Forwarded by Daniel Hess/Dallas/IBM on 05/07/2002
04:04 PM ---------------------------

"Tesla list" <tesla-at-pupman-dot-com> on 05/07/2002 09:22:12 AM

To:    tesla-at-pupman-dot-com
cc:
Subject:    RE: Zero Crossing Strobe



Original poster: "Colin Dancer by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<CMD-at-dataconnection-dot-com>

The only slight pain is that the chip (CA3059) went out of production last
year and is quite hard to get.  I have, however, found another more recent
chip which should perform the same function and will in due course release
an updated version of the circuit.

Colin.