Search found 49 matches

by Cai Arcos
Mon May 18, 2020 6:33 am
Forum: Images du Jour
Topic: Nathan Marshall - Fusor Progress
Replies: 41
Views: 4903

Re: Nathan Marshall - Fusor Progress

John:
I plan on buying 20kV 20mA diodes, with a trr of 100ns.
The capacitors are what worries me most, because everything else I've found with similar capacity and voltage ratings breaks the bank in my birthday fund.
by Cai Arcos
Sun May 17, 2020 11:47 am
Forum: Images du Jour
Topic: Nathan Marshall - Fusor Progress
Replies: 41
Views: 4903

Re: Nathan Marshall - Fusor Progress

Nathan: First of all, I want to express my gratitude for all the details provided about a superb build, especially the affordable power supply. I myself intent to imitate your efforts using a transformer I have found from a tube based CRT TV. The only problem are the capacitors themselves. The only ...
by Cai Arcos
Tue May 05, 2020 7:15 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Help with HV adjustable power supplies for radiation detectors.
Replies: 24
Views: 3226

Re: Help with HV adjustable power supplies for radiation detectors.

John: I think we are talking about different things. You probably reference something like this: https://www.mouser.es/ProductDetail/JKL-Components/BXA-24529?qs=sGAEpiMZZMvlvmHaYoGmZdvKIw2%2F%252BoHV5yU7qjc3YDs%3D . Which I have read about in Doug post "Standard HV Supply for detectors". I was talki...
by Cai Arcos
Mon May 04, 2020 7:46 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Help with HV adjustable power supplies for radiation detectors.
Replies: 24
Views: 3226

Re: Help with HV adjustable power supplies for radiation detectors.

John: That seems way too high. Taking the output directly the output at the transformer (thus avoiding any losses in the multiplier) we get a power 1.5 W (the 75V claimed times the *optimistic* 20mA). At 400V that is around 4 mA, which is respectable. Still, the noise is what worries me the most... ...
by Cai Arcos
Mon May 04, 2020 7:40 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Help with HV adjustable power supplies for radiation detectors.
Replies: 24
Views: 3226

Re: Help with HV adjustable power supplies for radiation detectors.

Hi: I was aware of the mosquitoe killing HV source. It is a "Joule Thief" like the one I previously discussed (i.e a blocking oscillator) with added voltage multiplication at the output. Thus, it's noise makes it unsuitable to my needs. What is the noise in the commercial module you described before...
by Cai Arcos
Fri Apr 24, 2020 8:22 pm
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: For what it is worth- a high power flyback article
Replies: 3
Views: 1024

Re: For what it is worth- a high power flyback article

The highest voltage I was able to achieve in a standard unit, insulating the best I could the pins, was 27 kV.
by Cai Arcos
Fri Apr 24, 2020 6:50 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: For what it is worth- a high power flyback article
Replies: 3
Views: 1024

Re: For what it is worth- a high power flyback article

From my experiences with this type of flybacks, pushing them higher than 30 kV is impossible, due to the isolation on the breakout pins of the board going toast (it seems that there is always a pin that is tap to the secondary winding, once the HV is on is easy to localize by turning off the lights ...
by Cai Arcos
Mon Apr 13, 2020 9:49 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Help with HV adjustable power supplies for radiation detectors.
Replies: 24
Views: 3226

Re: Help with HV adjustable power supplies for radiation detectors.

Hi: I've been using some time of the quarantine to work on the high voltage supplies. Unfortunately, due to somo environmental regulations I was unable to buy the inverters showed in a previous post, so I tried other ways. I *must* recommend to everyone interested in this type of work the App Note 1...
by Cai Arcos
Tue Mar 17, 2020 8:57 pm
Forum: Announcements and Site Administration Topics
Topic: Coronavirus pandemic
Replies: 160
Views: 25445

Re: Coronavirus pandemic

Hi: Here in Spain, we are becoming the "second Italy", mostly due to the ineffectiveness of the government to actually do something before the pandemic started growing, the secessionist leaders of various autonomies (specially Catalonia, where I live) not cooperating with the central goverment and t...
by Cai Arcos
Tue Feb 18, 2020 9:20 am
Forum: Images du Jour
Topic: An interesting little electrometer device.
Replies: 6
Views: 918

Re: An interesting little electrometer device.

Richard: I will eagerly await a more detailed description of the very interested device you have presented now! In the original FAQ post I quoted wikipedia for an invention date 1939. However, the best I found was this patent from 1962 with apparently no references: https://patents.google.com/patent...