[TCML] Measuring Voltage?

DC Cox resonance at wildblue.net
Sun May 23 22:54:19 MDT 2010

```This is not valid.

The diodes are not designed for the freq you are operating at.  The meter
may not be properly calibrated (do this with a known, calibrated 30-40 kV DC
power supply)

Best to just use the equation to do it:

Vsec = Vpri x 0.7 x SQR (Lsec / Lpri    This is very accurate.

Another method involves direct spark length measurement with an ignitron
primary trigger, but it's too much typing to explain it to you.

Dr. Resonance

On Sun, May 23, 2010 at 6:52 AM, Neal Namowicz <neal at imagesbyneal.com>wrote:

> I wanted to ask if whether or not the primary, or secondary, voltages can
> be measured with a meter. Here's what I did, and I don't know if my meter is
> that far off, or if there is something else affecting the readings that I'm
> not aware of. I have an old KV meter from an x-ray machine with a range of
> 40kv to 140kv dc. I attached a couple hv diodes to the meter and attached it
> to the secondary electrodes on a bi-pole coil. The needle was pegged almost
> immediately when I started to apply power. Then I switched it over to the
> output on the transformer (9kv, 30ma nst).  With the variac at about 1/4
> power, the meter was registering 100kv. Not what I expected.
>
> So I have a couple questions here; first, why is the primary voltage
> reading so high with this meter? I'm thinking that the meter is showing the
> voltage rise due to resonance, perhaps? If that's the case, is there any way
> to accurately measure the voltage? I'm actually more interested in knowing
> secondary output. How can one go about measuring, even "guesstimating" the
> approximate output on a coil? I'd like to have a somewhat more accurate
> answer for people when they ask what the voltage is of the arcs. Can my
> bi-pole coil be putting out more than 140ish kv at such low power? Thanks in