Search found 113 matches

by Michael Bretti
Fri Jul 05, 2019 3:56 pm
Forum: Items For Sale
Topic: [REQUEST] 1 kV 10 A Diode and 10 kV Cable
Replies: 8
Views: 3591

Re: [REQUEST] 1 kV 10 A Diode and 10 kV Cable

Joshua, No need to worry too much about the diodes on the transformer output - running a DC ion gun to pre-ionize the background gas won't directly affect the pulse input or cause reflections directly. Also, noise from the gun won't affect pulse output going into the fusor. I wouldn't stress too muc...
by Michael Bretti
Fri Jul 05, 2019 2:11 pm
Forum: Items For Sale
Topic: [REQUEST] 1 kV 10 A Diode and 10 kV Cable
Replies: 8
Views: 3591

Re: [REQUEST] 1 kV 10 A Diode and 10 kV Cable

Joshua, Which diodes are you using these for specifically? In your system you have a few sets of diode stacks that perform different functions (if you are also using preionization as well). The first is to protect your charging supply, probably safe to be double your input, so only maybe 20kV, 1A is...
by Michael Bretti
Tue Jul 02, 2019 12:25 am
Forum: Items For Sale
Topic: 8 H charging choke request
Replies: 1
Views: 1936

Re: 8 H charging choke request

Joshua, No need necessarily for a massive charging choke for your system at all. I would just use some decent wattage high voltage charging resistors to limit current, as well as a suitable HV diode for protection, which can easily be found at the voltage and current levels you are after quite cheap...
by Michael Bretti
Thu May 16, 2019 2:33 pm
Forum: Images du Jour
Topic: Successful Completion and Operation of the Integrated High Vacuum Test Stand and Micro Propulsion Testing Chamber
Replies: 13
Views: 7715

Re: Successful Completion and Operation of the Integrated High Vacuum Test Stand and Micro Propulsion Testing Chamber

Ian, You can actually see all of the details and specifications for the thrusters, as well as all projects I work on at the Applied Ion Systems website. I won't take up server space here posting lots of detailed photos, but you can find significant details for everything there. I also post updates r...
by Michael Bretti
Sat May 11, 2019 6:10 pm
Forum: Images du Jour
Topic: Successful Completion and Operation of the Integrated High Vacuum Test Stand and Micro Propulsion Testing Chamber
Replies: 13
Views: 7715

Re: Successful Completion and Operation of the Integrated High Vacuum Test Stand and Micro Propulsion Testing Chamber

Patrick, Certainly a very interesting problem. In terms of the lower limit for pulse widths for magnetic fields, I would not take the number I gave as a lower limit by any means, I just gave an estimate based off things I knew directly off the top of my head for more conventional high power pulsed s...
by Michael Bretti
Sat May 11, 2019 12:48 am
Forum: Images du Jour
Topic: Successful Completion and Operation of the Integrated High Vacuum Test Stand and Micro Propulsion Testing Chamber
Replies: 13
Views: 7715

Re: Successful Completion and Operation of the Integrated High Vacuum Test Stand and Micro Propulsion Testing Chamber

Rex, The project did cost a good amount, however no more total than any other well-designed fusor system (few thousand dollars total). I ended up spending a significant amount of time waiting and searching for the best deals I could find for parts, and designing my system around what was available. ...
by Michael Bretti
Thu May 09, 2019 5:23 pm
Forum: Images du Jour
Topic: Successful Completion and Operation of the Integrated High Vacuum Test Stand and Micro Propulsion Testing Chamber
Replies: 13
Views: 7715

Re: Successful Completion and Operation of the Integrated High Vacuum Test Stand and Micro Propulsion Testing Chamber

Yeah, the Teflon PPTs are pretty interesting in their operation, and are very promising for miniaturization from the standpoint of no pressurized gas, liquid metal sources, or any difficult fuel-handling needs, as well as very low power consumption requirements. Very robust and relatively low cost c...
by Michael Bretti
Thu May 09, 2019 2:09 pm
Forum: Images du Jour
Topic: Successful Completion and Operation of the Integrated High Vacuum Test Stand and Micro Propulsion Testing Chamber
Replies: 13
Views: 7715

Re: Successful Completion and Operation of the Integrated High Vacuum Test Stand and Micro Propulsion Testing Chamber

Richard, Thank you for your compliments. The thrusters I will be focusing on for now are solid Teflon fuel pulsed plasma thrusters. No gas inlet or flow rates to measure. The fuel is provided through ablation of the Teflon fuel first through an ignition arc, which raises the localized pressure betwe...
by Michael Bretti
Thu May 09, 2019 3:40 am
Forum: Images du Jour
Topic: Successful Completion and Operation of the Integrated High Vacuum Test Stand and Micro Propulsion Testing Chamber
Replies: 13
Views: 7715

Successful Completion and Operation of the Integrated High Vacuum Test Stand and Micro Propulsion Testing Chamber

After a year of intensive research, design, simulation, and building, I have finally run the Integrated High Vacuum Test Stand at high vacuum levels with all subsystems for the first time last week. Over the course of the year I have posted extensive walkthrough details regarding the design process,...
by Michael Bretti
Wed Jan 16, 2019 3:49 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: How to figure out the specs of old Rigaku scintillation tube probe?
Replies: 24
Views: 9472

Re: How to figure out the specs of old Rigaku scintillation tube probe?

Harald, I would strongly suggest you research more into the fundamentals of beam systems, beam optics, and beam instrumentation to save yourself a lot of frustration and money pursuing methods that will not yield results you are looking for. While you can reverse the polarity of a gun and use it as ...