Search found 1030 matches

by Rich Feldman
Fri Jul 10, 2020 12:54 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Vacuum Chamber Construction
Replies: 100
Views: 31705

Re: Vacuum Chamber Construction

Good clean toes. :-) Assuming the main ring welds aren't leaking ... Is it possible that a thick steel ring was rendered non-flat, beyond tolerance, by the welding operations? I guess that could be checked by assembling without Cu gasket, all bolts finger tight, and check the joint all the way aroun...
by Rich Feldman
Thu Jul 09, 2020 2:05 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Vacuum Chamber Construction
Replies: 100
Views: 31705

Re: Vacuum Chamber Construction

Anybody here using nut plates instead of single nuts, to use fewer wrenches and lockwashers?
CF-Flange-Plate-Nuts.png
CF-Flange-Plate-Nuts.png (75.69 KiB) Viewed 61 times
https://apexvacuum.com/product/conflat- ... late-nuts/
by Rich Feldman
Sun Jul 05, 2020 1:04 am
Forum: FAQs: Fusion and Fusor Theory
Topic: Fusion energy from a D-D reaction + A bit of Fusion Physics
Replies: 6
Views: 805

Re: Fusion energy from a D-D reaction + A bit of Fusion Physics

Right you are. Technologically easiest path needs tons of natural uranium and even more tons of boron-free graphite, as demonstrated 78 years ago. If you came to have a bunch of highly enriched uranium, making a controlled fission reactor from it would be harder than making a bomb. And making a prac...
by Rich Feldman
Sun Jul 05, 2020 12:34 am
Forum: Fusor and/or General Fusion Theory (& FAQs)
Topic: Gaining some energy back from our fusion reactors
Replies: 11
Views: 485

Re: Gaining some energy back from our fusion reactors

Suppose you could magically capture 100% of the energy released by D-D fusion events in these fusors. Do you understand that it's no more than 1/1,000,000,000 of the electric power we put in to the fusor? It would be 1 billion times more efficient to skip the fusor, and send what would have been fus...
by Rich Feldman
Sun Jun 28, 2020 9:55 pm
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Home Built Metering Panel
Replies: 10
Views: 6040

Re: Home Built Metering Panel

Ed, thanks for clarifying that you got special high voltage resistors. Looks like a nice conservative design. Is the estimated bottom-line accuracy OK? (Gain can be trimmed using ordinary resistors, series or shunt, if you have access to a HV reference source or meter.) I bet inner tube would be war...
by Rich Feldman
Sun Jun 28, 2020 4:32 pm
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Home Built Metering Panel
Replies: 10
Views: 6040

Re: Home Built Metering Panel

Nice report, Ed. Can we see more detail about design of the HV metering resistor string? In particular, the voltage rating of the individual R's. Not the same as value computed from power rating and resistance; the voltage rating usually gets you first when R value is many megohms. Not necessarily i...
by Rich Feldman
Tue Jun 23, 2020 2:09 pm
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: Still not desired resolution (new scint from GEO)
Replies: 25
Views: 6763

Re: Still not desired resolution (new scint from GEO)

Very interesting to read about tapered PMT voltage dividers, I guess related to linearity of the charge multiplication. Nice idea about embedding the bias tee to eliminate some cable and connectors. This is a chance to point out (for noobs) a simple thing about transmission lines. No coincidence tha...
by Rich Feldman
Mon Jun 22, 2020 10:50 pm
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Transformer Input Meanings
Replies: 6
Views: 449

Re: Transformer Input Meanings

Still haven't seen anything about you in Please Introduce Yourself forum. If you are grown up and experienced with ebay, then I guess you are prepared to pick up that big old Rigaku thing in Oxnard, California. And know better than to offer more than half of the buy-it-now price ( seller has the opt...
by Rich Feldman
Mon Jun 22, 2020 2:34 pm
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Transformer Input Meanings
Replies: 6
Views: 449

Re: Transformer Input Meanings

Agree with Jerry that the smallness implies high frequency. Compare size not with bare dental transformers (7 to 15 mA in 1-second bursts), but with potted 100 to 200 mA transformers for whole-spine radiography. I can attest that the Bennett cathode and anode tanks need HF drive, in fact are designe...
by Rich Feldman
Sat Jun 20, 2020 11:54 pm
Forum: Fusor Construction & Operation (& FAQs)
Topic: Would the Makezine.com fusor even be considered fusion?
Replies: 6
Views: 476

Re: Would the Makezine.com fusor even be considered fusion?

The reporter telling the story glossed over some important details. For example in pretty picture at top, the glowing M and T appear to be in chambers with pressures 100 times too high for a tradtional fusor that fuses. Reporter says: "When voltage is applied ions are drawn to the center, where they...