Re: Bad monitor discharge instructions

I guess what I was looking for was the number of Joules stored in the tube.
So are we talking one Joule or how many?

As for being discharged, well, the tube had been sitting under the bench
for about one year with no chassis attached. Rather discharged I think, but
I did short it out with a jumper for a minute to be real safe...meters
handle 500VDC on there cap analyzing function-at least this meter does...

John :-#)#

At 12:42 AM 12/20/1999 -0600, you wrote:
>Current is voltage divided by resistance. So 20 kV into a short is one
>hell of a
>lot of current for a very short time. Into 20 kohms you would initially
>have 1 amp
>decaying exponentially to zero. Assuming 2000 pF of capacitance and 20
>kohms you
>would have a time constant of 40 uS. So every 40 microseconds the voltage and
>current will decrease by about 67 %. It never actually gets to zero, but
>for all
>practical purposes it is assumed to be zero after 5 time constants (200
>microseconds, in this example).
>
>Your reading was based on the response time of whatever meter you were
>using. I
>wouldn't be trying that with a digital meter if you will be needing to use it
>again, there is a very real danger of blowing out parts.
>
>John Robertson wrote:
>
> > For anyone that remembers the formula (or can find it) for the amount of
> > current stored in a capacitor, I measured a 13 inch picture tube on
> > Saturday and came up with a value of 0.001 (102). This was between the
> > anode cap and the chassis that it was mounted in. The tube was not
> > connected to anything else.
> >
> > So @ 20KV what are we talking about? I left my Nomographs sitting on the
> > filing cabinet.. somewheres...
> >
> > John :-#)#
> >
> > At 11:26 PM 12/19/1999 -0500, you wrote:
> > >I agree this is the best course. It will ruin the topic of my radio
> show, but
> > >hey, that's better than crispy newbies!
> > >
> > >-Al-
> > >
> > >saint wrote:
> > >
> > > > I emailed the owner of the web site with the bad monitor discharge
> > > > instructions to tell him conventional wisdom was that he was in
> error - if
> > > > he wants to see them, I was thinking of forwarding the
> > > > discussion from Vectorlist on his web page, with names/emails removed.
> > > > Before I did so, I wanted to make sure no one objected?
> > > >
> > > > --- saint
> > > > Build Your Own Arcade Controls FAQ
> > > > http://www.arcadecontrols.speedhost.com
> > > >
> > > > On Mon, 13 Dec 1999, saint wrote:
> > > >
> > > > > I was thining about it, but didn't want to get into a flame war,
> > > > > particularly since I can't speak from any position of
> > > > > personal-certainty-of-knowledge...
> > > > >
> > > > > --- saint
> > > > > Build Your Own Arcade Controls FAQ
> > > > > http://www.arcadecontrols.speedhost.com
> > > > >
> > > > >
> > > > > On Mon, 13 Dec 1999, Christopher X. Candreva wrote:
> > > > >
> > > > > >
> > > > > > One thing this show reminded me of -- did anyone ever contact the
> > > person
> > > > > > with the alternate cap-kit instructions, and actually tell him his
> > > > > > method of tube discharging is -- suboptimal ?
> > > > > >
> > > > > > :-)
> > > > > >
> > > > > > -Chris
> > > > > >
> > > > > > ==========================================================
> > > > > > Chris Candreva -- chris@westnet.com -- (914) 967-7816
> > > > > > WestNet Internet Services of Westchester
> > > > > > http://www.westnet.com/
> > > > > >
> > > > > >
> > > > >
> > > > >
> > >
> > >--
> > > =====================================================================
> > >-= Al Warner batlzone@cyberenet.net =-
> > >-= Learn how to install a Cap Kit in your video game's monitor and =-
> > >-= see a whole lot more on my web page at: =-
> > >-= http://www.cyberenet.net/~batlzone =-
> > > =====================================================================
> >
> > John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
> > Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
> > http://www.flippers.com
> > "Old pinballers never die, they just flip out."
>
>--
>Windows:
>
>32 bit graphical interface for a
>16 bit patch for an
>8 bit operating system written for a
>4 bit processor by a
>2 bit company that can't stand
>1 bit of competition.

  John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
  Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
  http://www.flippers.com
         "Old pinballers never die, they just flip out."
Received on Mon Dec 20 01:23:10 1999