Camilo wrote:
well, so what you say about the best ability to ionize of high
frequency HV, does apply also to pulsed DC? I mean ¿Is It better to
ionize using high frequency pulses of HV than low frequency pulses of
HV (or DC HV)?


There's no "best", since it really depends on the needs of your
application.

Simple home negative ion generators will work fine with low current HVDC
from a small voltage multiplier (a few kV).

Industrial electrostatic precipitators or electrostatic separators
require significantly higher HVDC voltages (50 kV, 10's or even 100's of
mA) and currents.

For making non-equilibrium air plasmas (such as ozone generators or
chemical reaction chambers for pollution control), high frequency
barrier discharges or pulsed discharges are often the most efficient
methods.

Ion generators for electrostatic discharge (ESD) neutralization use AC
or pulsed DC corona discharges to generate ions of both polarities. Here
are a couple of articles that discusses ionization and air ionizers (for
ESD suppression):

http://www.tkb-4u.com/articles/other...ionization.php
http://www.ce-mag.com/archive/06/ARG/steinman.htm

If you're looking for a simple negative ion generator for home use,
there are LOTS of ads and claims by various manufacturers, but much of
this is colored by unsubstantiated claims and advertising hype.

What is your application??

Bert
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What is your application??

well, initially just testing, and maybe an air ionizer (negative
ions), my thought block diagram is like this: first a compressor or
fan to send air thru a pipe, inside this pipe there are a conductive
grid covering all its cross section (someone here recommended me to
use steel wool), and to this grid is connected the HV source, so my
only problem is to have the suitable HV source for me (small, simple
and ideally motionless to avoid problems associated with mechanisms ).
Theorically air must come out from the pipe negative ionized .

Domestic ion generators do not work in dry air.
¿Is this because moist air is easier to ionize than dry air and
ionizer can use a lower ionization voltage?

I have another question (half OT) ¿where can I find a schematic of a
hand buzzer, that think what shocks a victim when gives a handshake to
prankster? ¿which is its output voltage? ¿why am I asking this?, it´s
just because I think that circuit can be useful as HV source, or at
least as a base circuit for a HV source, ¿or am I wrong?

"Camilo"

Domestic ion generators do not work in dry air.
¿Is this because moist air is easier to ionize than dry air and
ionizer can use a lower ionization voltage?

It is known for ages that dry air do not "destroy" a charge on a charged
body. Only moist air does it. It means that electrons do not like vacuum
and N2, O2. Electrons like only H2O. It take place at each voltage. So it is
not ionization but ratcher charging. All particles suspended in the air are
charged.
S*

hmmm... another question: ¿which is the noble gas with the lowest
ionization voltage? ¿which is this voltage?

"Camilo" wrote
...
hmmm... another question: ¿which is the noble gas with the lowest
ionization voltage? ¿which is this voltage?

The voltage is strongly pressure dependent. Lower pressure lower voltage.
But you need: "Theorically air must come out from the pipe negative ionized
"

I know that in: "first a compressor or fan to send air thru a pipe, inside
this pipe there are a conductive
grid covering all its cross section ." you can charge negatively vapour,
paint, dust and similar air contaminations. I know nothing about dry clean
air or noble gas.
Can anybody help?
S*