Re: Floating Scopes

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

Original poster: "Nicholas Field by way of Terry Fritz <twftesla-at-qwest-dot-net>" <nick.field-at-hvfx.co.uk>

Hi Winston,

If you can faraday screen it effectively then there should be no problem.
Greg Leyh used a laptop scope inside the sphere of his BIG coil to measure
streamer currents in the megavolt level output without any problems.

You will have to be careful how you install it.  I would suggest that a
stacked toroid arrangement, with the space between the two toroids filled by
a chicken wire cylinder and the scope inside the wire, would provide great
sheilding without compromising the performance of the coil unduly. Of course
the precise arrangement depends on your coil.

You might want to point a good video or stills camera at the scope as well
as the binoculars, I find it much easier to evaluate things properly in the
peace of my study than with massive sparks flying around the place!   If you
do go ahead with this experiment be sure to post the results somewhere.

Safe Coiling
Nick
_______________
Nick Field, HVFX
www.hvfx.co.uk

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, December 05, 2002 2:27 AM
Subject: Floating Scopes


 > Original poster: "Winston Krutsch by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <u236-at-earthlink-dot-net>
 >
 > Hi All,
 >
 > I just bought a cute little Tektronix model 321 scope.  It is rated to
 > only 5 MHz, but that's OK, since it's battery powered, and was built
 > before 1963 :-)).  It's all solid state, too (not sure if that's good or
 > bad, yet).
 >
 > Anyway, I was wondering if I could stick this thing on the inside of my
 > toroid for making topload current measurements, without letting out its
 > smoke.  I'd then view the screen from the coil's controls via binoculars
 > ;-)).  My gut says "no", since the scope's components use the case as a
 > ground, and RF might make things a bit messy.  Comments???  I know I
 > could float it at a high DC potential, but I'm not sure about RF.
 >
 > At any rate, I'm glad that I don't need to haul my Tek 545 outside
 > anymore, unless I need to make high frequency measurements ;-)).  Also,
 > did Tektronix make any battery powered tube scopes?
 >
 > Thanks,
 > Winston K.
 >
 > PS-I got the thing for $50, because there was something wrong with it.
 > When I took the case off, the "problem" was that both of the horizontal
 > plate connections to the CRT had been disconnected!  I put them back,
 > and all was well :-)).
 >