Hi,Christian
The tube is a capacator.
j.


Mar 9, 10:17*am, wrote:
Hello!
I tried to measure a short high Voltage peak with a little older
Tektronix Probe, Part No. 010-025 on a Tektronix TDS 460 Memory-Scope.
Concretely I wanted to define the ignition voltage of a fluorescent
tube. I guess the voltage is about 1-2 kV (1m length of the tube). I
measured between 7 and 8 kV with the Tektronix Probe (!) and disagreed
with that, because the C_res on the Ballast-Board has a voltage
strength of 1,6 kV and the expected voltage that I got from a gas
discharge graph is about 1 kV/m.

I quantified the divider of the probe with 979:1 on 50 Hz sinus AC,
linear with different voltages between 100 and 400 V which I could set
up on the isolating transformer.

Now the question:
Can somebody help to affirm this variation?
Is there overshoot common because of the short voltage spike?

Thanks for all consideration!

greetings,
Christian