Re: Ampliphone HV-other options?!

You can be connected to the CRT, just unplug the
neck board.

Resistor? Just where do you think you're going to find
a resistor that can take that kind of voltage? A HV
probe would do it, but without the capacitance of a
CRT present the reading on the probe will be wrong.

Be careful what you use for the transistor. The flyback
pulse at the transistor collector is REAL close to 1,000
volts! And the resonating capacitors must be able to
withstand that, too. Without the capacitors that pulse
will TRY to go to infinity, that's why monitor makers
are real picky what they use there. It's also why they
use multiple smaller value capacitors, if one goes open
the pulse doesn't get too wild.

John Robertson wrote:

> Hi Clay!
>
> You can't generate X-Rays without a vacuum, and a target (like inside a
> picture tube or X-Ray tube)...just raw HV won't do it, otherwise those
> folks living under/near transmission towers might have a problem...you
> thus do not need to load down the HV.
>
> John :-#)#
>
> Clay Cowgill wrote:
> >
> > > We could hook up (backwards) a 50v
> > > (25vct) transformer to the output of the 50v transformer supplying the
> > > power to the monitor to get 120volts, but it's probably easier just to
> > > find an isolation transformer. Up until the most current generation
> > > of WG monitors, one was required, there must be many floating around.
> > >
> > I think we can get 1:1 isolation transformers for probaly $10-12 each.
> > Maybe even less $$$ since we don't need as much current as "usual" (not
> > driving the color guns and deflection off it).
> >
> > So is it "safe" for an HV transformer to have its anode coupled to ground
> > through a resistor? (To just burn off the HV output without having to hook
> > it up to an actual CRT.) Might not want to be generating soft x-rays while
> > figuring things out...
> >
> > -Clay
>
> --
> John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
> Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
> mailto:jrr_at_flippers.com, web page http://www.flippers.com
> "Old pinballers never die, they just flip out."
Received on Sat Jun 12 02:33:54 1999