Alpha Spark Detector
This video shows a rather fun little device that can be called an Alpha Spark Detector. I found out about it from Carl Willis and built one of my own a few years ago. And couldn't get it to work.
I drug it out from a dusty corner and worked on it last week. And it sort of worked. And then stopped working. So I rebuilt it. And it sort of worked. So I changed the design. And it sort of worked. And rebuilt it again. Ditto. And finally now.
For such a simple thing there are lots of pitfalls. Dielectric proximity to the spark area causes misfires. Dust, ditto. Electrode wear. As I mentioned in the video reversing the potential stops all function. Huh?
Tips for other builders:
1) Use heavy construction or else the wires will distort the fixture. then your earlier wires will sag as you put in the later wires.
2) 150pF or so is good for the spark visibility. Larger will start to damage the wires. I am using 1Mohm in series with my power supply with the 150pF shunting the two electrodes.
3) Tungsten wire sounds like it might be a good idea to deal with spark erosion. Don't have a clue how to pull it into straight lines and make it stay.
4) The smaller the wire the better it works. I'm guessing that corona ionization from the thinner wires is important.
Cheers.
Alpha Spark Detector
This video shows a rather fun little device that can be called an Alpha Spark Detector. I found out about it from Carl Willis and built one of my own a few years ago. And couldn't get it to work.
I drug it out from a dusty corner and worked on it last week. And it sort of worked. And then stopped working. So I rebuilt it. And it sort of worked. So I changed the design. And it sort of worked. And rebuilt it again. Ditto. And finally now.
For such a simple thing there are lots of pitfalls. Dielectric proximity to the spark area causes misfires. Dust, ditto. Electrode wear. As I mentioned in the video reversing the potential stops all function. Huh?
Tips for other builders:
1) Use heavy construction or else the wires will distort the fixture. then your earlier wires will sag as you put in the later wires.
2) 150pF or so is good for the spark visibility. Larger will start to damage the wires. I am using 1Mohm in series with my power supply with the 150pF shunting the two electrodes.
3) Tungsten wire sounds like it might be a good idea to deal with spark erosion. Don't have a clue how to pull it into straight lines and make it stay.
4) The smaller the wire the better it works. I'm guessing that corona ionization from the thinner wires is important.
Cheers.