Electronics > Beginners

Measuring voltage (and frequency) of spark

<< < (4/4)

petert:

--- Quote from: tautech on December 22, 2019, 09:10:40 am ---See if you can find any Pintek HV probes sold locally:
http://www.pintek.com.tw/files/pintek/HVP-provided-Fig.pdf

--- End quote ---
Thanks. They look interesting, however what I found is around 270€, and my scope is just a Rigol 1054Z, so it's pretty close in price haha.
(for future reference: https://www.reichelt.de/hochspannungs-tastkopf-40-mhz-passiv-bis-20-kv-testec-hvp-15-b-p267712.html)

tautech:

--- Quote from: petert on December 22, 2019, 09:42:16 am ---
--- Quote from: tautech on December 22, 2019, 09:10:40 am ---See if you can find any Pintek HV probes sold locally:
http://www.pintek.com.tw/files/pintek/HVP-provided-Fig.pdf

--- End quote ---
Thanks. They look interesting, however what I found is around 300€, and my scope is just a Rigol 1054Z, so it's almost the same price haha.

--- End quote ---
Then keep an eye on the 2nd hand market.  ;)

If you think HV probes are expensive then start looking at decent current probes !
I recently got a 100 MHz Tek P6022 for just $145 US to go with my 60 MHz P6021 and new they're $3k ! ! !
Want a good AC/DC current probe expect to pay even more, lots more.

The cost of a scope itself is just the start and to be well equipped to measure all manner of things you will always pay more for good accessories than the scope itself.

joeqsmith:

--- Quote from: petert on December 22, 2019, 09:01:46 am ---
--- Quote from: tautech on December 20, 2019, 08:45:50 pm ---1000:1 probes for scopes are not that expensive.
Look up Joe Q Smith's DMM test videos where he uses grill ignitors and builds a 1000:1 probe so to see and measure the waveforms.

--- End quote ---
I suppose you mean this video?

--- End quote ---

A few comments.    The homemade differential probes I made all have a fairly low bandwidth and voltage rating.    The box used to measure the AC power uses some odd ball transformer that again would have a fairly low bandwidth.   

If you really wanted to look at a spark with a scope you would need something fast.  The large HV probe I made is a 10,000:1, not 1000:1.  I built it to monitor the transients I apply when bench marking DMMs.  While these transients are far beyond what a typical cheap HV probe could measure, they are about 1000X slower than a spark.   While I did show this probe looking directly across a spark gap when I was looking for where the breakdown problems would be, its really not fast enough to show the waveform.   You can see that testing here (shortcuts are all close to the relative parts, you may need to skip around a bit).
https://youtu.be/OUfWYwPB9uI?t=305

Me reading a few paragraphs from an old RCA applications book on car ignitions.   Again, just a little background on what to expect.
https://youtu.be/bgz-pqg0rKo?t=1177

When I looked at the grill starter, I show the IEC standard and how I measured it.  You can find that in the UT181A PartB, here:
https://youtu.be/1kYcY2ogmqo?t=125

I ended up making a better spark gap and here you can see some of the data I collected for it. Again though, I am looking at current.  Note the rise and delay times. 
https://youtu.be/Qimtx8z6FUQ?t=132

Attached pictures looking at the output from one of my ignitions with a homemade capacitive probe and my current transformer.   This is my first real DSO which has a BW of 4GHz.  I am really only interested in making relative measurements and would need to improve the setup to see what the waveforms actually look like.   Nothing $$$ wouldn't solve.

joeqsmith:

--- Quote from: petert on December 22, 2019, 09:21:39 am ---
--- Quote from: joeqsmith on December 21, 2019, 05:06:19 pm ---Did you made your coherer and can you post a picture of it?   

--- End quote ---
It's not the clearest, because I used it several times already and the flexible tube has become a bit tarnished.
I also adjusted it several times (moving the screws to adjust the distance) until I found a working "configuration", tapped it to decohere it, so that some of the filings are "spread out" on the screw threads.
The filings are of Cupronickel, a mix of copper and nickel (75 % Cu, 25 % Ni).
(Attachment Link)
Full resolution pic (click to zoom):
(Attachment Link)

--- End quote ---

 :-+ I would vote this post of the week if I could.   It's always good to see people experimenting.

Navigation

[0] Message Index

[*] Previous page

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod