Coils for Ion

[garfield at pilgrimhouse.com]

On Thu, 04 Jun 1998 01:57:17 -0500, Walter Petermann
<corsaro at brokersys.com> wrote:

>  ..I get the same, ~150Khz. I have read that the Ion
>current measuring circuit should have a bandwidth of 10Khz

I dunno about the absolute numbers, but ratio's in keeping with the
appearance of the "representative signal waveforms" in that web page
pix. Like I said before, it looks like the secondary's natural frequency
is around 10X the ION current waveform, judging from the shape &
rise/fall times of the ionization current.

> (1). Maybe this is a way around the problem of 'electrostatic fouling'
> (2) when high bias voltages are used between electrodes.
>
>What if question:
>If you apply a 400v, 50Khz-100Khz ac signal as the 'bias'.
>Would this eliminate the fouling since the signal is ac?
>Then you could recover the Ion signal (like recovering a
>radio AM signal) with a diode and a 10Khz filter.

Hmm, now that's an interesting and novel idea; I don't think I've seen
that ever suggested for getting around the "electrostatic fouling". Sure
sounds like it might work, tho. Neat idea, worth trying, fer sure.
Complicates the electronics a tad, but hey, that's not the point; the
question is can you use ac to avoid the electrostatic effect? Now you're
talking REAL research, dude.

I guess that means you can count on spending alot of time proving out
the idea. B)

Gar