Search found 41 matches

by John Myers
Thu Jan 18, 2018 11:36 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: High Voltage Supply for PMT
Replies: 9
Views: 183

Re: High Voltage Supply for PMT

I think it's an 'economy of scales issue' where it's not really worth it for distributors like Mouser and Newark to sell CCFL transformers anymore. Especially with LED's taking over. You'll likely need to buy straight from the manufacture. CTX210609-R is obsolete but there may be other similar parts...
by John Myers
Wed Jan 17, 2018 4:31 am
Forum: The Trading Post
Topic: Does anybody want 40kv wire?
Replies: 2
Views: 137

Re: Does anybody want 40kv wire?

What gauge is the wire?
by John Myers
Mon Jan 08, 2018 3:34 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: The Beginnings of a Fusor Electrical System
Replies: 53
Views: 6211

Re: The Beginnings of a Fusor Electrical System

The center tap of that transformer is grounded to its own metal case.

The meter and sense resistor is connected in between system ground and the metal case of the transformer.
by John Myers
Thu Jan 04, 2018 9:57 pm
Forum: Books & References
Topic: SolveSpace CAD
Replies: 3
Views: 163

Re: SolveSpace CAD

The major selling point would be that it's open source; for those who find that important.
by John Myers
Thu Jan 04, 2018 9:52 pm
Forum: Ion Gun Design and Construction (& FAQs)
Topic: Electrometers and Picoammeters
Replies: 14
Views: 447

Re: Electrometers and Picoammeters

Would be nice to make the rest of the circuit with op amps, for example, rather than endless carefully matched bipolars and passives everywhere.
You can use an op-amp or two to replace the analog backend since op-amp are just a packaged version of all that circuitry.
by John Myers
Thu Jan 04, 2018 5:22 am
Forum: Books & References
Topic: SolveSpace CAD
Replies: 3
Views: 163

SolveSpace CAD

SolveSpace is a free and open source [GitHub] computer aided drawing program (CAD).
I haven't used it yet but it looks like it could be a good choice for modeling fusor's and ion guns.
by John Myers
Mon Dec 18, 2017 6:54 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Thoughts on backplanes and card cages.
Replies: 7
Views: 243

Re: Thoughts on backplanes and card cages.

There are definitely a lot of choices for a backplane architecture.

VXI or PXI could be a good choice also.
Ones like uTCA and ATCA have lots of high speed lines on them making the chassis' and modules expensive.
by John Myers
Thu Dec 07, 2017 4:17 am
Forum: Images du Jour
Topic: A nice Surplus item to make a Neutron Detector Power Supply
Replies: 6
Views: 454

Re: A nice Surplus item to make a Neutron Detector Power Supply

The vacuum tube is likely a thyratron. Do you see a part number? The trigger amplifier I got from an auction also has a thyratron, an inductor (though much smaller) and a cap at the output. I believe the cap and inductor are for creating the pulse shape when triggered from the thyratron. It looks li...
by John Myers
Thu Nov 16, 2017 6:10 am
Forum: New User Chat Area
Topic: Serial communication
Replies: 14
Views: 447

Re: Serial communication

So, I'm not that familiar with Arduino but when you say serial monitor that's through the USB correct?
Your code looks like its trying to write the value back to the sensor instead of a different serial port.
by John Myers
Thu Nov 16, 2017 5:13 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: 50kv Spellman PTV Power Supply Setup
Replies: 4
Views: 361

Re: 50kv Spellman PTV Power Supply Setup

Wow, your making things more complicated then they need to be. Just follow figure 3.2 B which only needs two 20K potentiometer and two 100 ohm resisters. You don't even need an external supply (pin1). Like Silviu said, LED dimmers use PWM control or control the current output neither of which you wa...