Fusor Forums

I bought some high voltage equipment from an auction.

Wow, that is a lot of heavy metal! Well, looks like you have both a complex but extremely interesting project getting that stuff working!

I'd really like to hear, as you progress, what you are doing to get the various components working; or if you will side step some of that and create a new pulse system for the x-former (maybe, if you know, some details on how that x-former works.)

That 130 kV x-former really looks like it can deliver the current along with those volts - that is one big monster.

So, do keep us posted on your work once things start to progress - that project really looks exciting and fascinating!

Also, thanks for posting the images.

Ooh! Ahh!

Those big caps are labeled 500 uufd. I think most manufacturers had switched from uufd to pf by some time in the 60's, so that's some pretty vintage stuff. Hope the internal magic hasn't evaporated.

I don't have any concrete plans for the spark gap xformer, I thought I might regret not getting it later and should rescue it from the metal scrapers who seem to be bidding on items like that. I haven't found any info on it yet, I'm not exactly sure how it works so I'll probable open it up and take a look.

It looks like it was a bunch of old equipment from the Los Alamos national lab. I also got 4 pwr supplies for Oscopes. Here's a youtube video of someone showing the insides.

I didn't even think about how old the caps were until few day's after I bid on them. I spent about $2 each so I think it's still worth the gamble.

I was told that the items in the pictures below were part of a nitrous system. So I got them too, just out of curiosity. One seems to be a pump or compressor and the other ended up having a large cap inside.

That's a hydrogen thyratron on the end of that one thing. Marked Res (reservoir) and HTR (Heater filament). Some sell for decent money on ebay.

That's great!
I assumed that the tubes meant it was some sort of pump but it must be for cooling the thyratron.

That 130 kV transformer looks fairly complete/turn key (except for the drum and oil.) I believe those horizontal stacks are the HV diodes. Does it indicate what voltage and frequency it needs in the primary in order for it to operate? Also, have you ohm tested the primary and secondaries to see if they are ok?

I had to leave on a business trip right after I got them so I didn't have time to checkout/test anything. It will be another whole week before I get back

I got two of them but only one had a label, which is faded. I'll check again when I get back to see if there's any other labels somewhere with those specs.

You might be interested to know that the original Farnsworth fusor team used a Universal Voltronics 150kv 50ma power supply in their work back in the 50's and 60's. According to Jean Meeks the supply was in a fiberglass drum larger than a 55 gal oil drum and with oil weighed in at over 1500lbs. Jean told me they had to move it twice and had to remove two doors to the lab to get a fork lift in the lab to move it each time.

Richard Hull

I checked for the input voltage specs on the 130KV Voltronics supplies but don't see any. I'll try my luck and try to contact the company and see if they'll give up and information on it.

The device with the thyratron also had a large capacitor in it.

While little can be determined from a single picture of wires going to a transformer - I would speculate (i.e. wild guess) that the two black wires feeding the main transformer could indicate single phase 120 Volt or maybe, 208 volt. Of course, those wires may be sense wires or something else entirely. Maybe more pictures of the transformer and its layout system and any other related lead attachment points might help others here make a more intelligent determination than my unsubstantiated guess.

That rather modern EG&G deuterium thyratron needs about 15 amps for the filament and can switch over 20,000 amps at 32,000 volts. A 640 megawatt peak pulse tube. A microsecond or so pulse, of course.

Try and switch that with silly-con! EG&G was bought out, it is now Perkin Elmer Corp. The tube still seems to be available. I have a large number of H2 and D2 thyratrons, having used a few in Tesla coils and a water arc gun to replace the spark gap.

Richard Hull

It's hard for me to even envision a 20,000 amp pulse. I wont be generating 20KA pulses anytime soon... or ever, but at least I'll have a thyratron with lots of 'headroom'.

In order to get some pictures of the transformer I tried taking the 130KV supply apart from the bottom so I wouldn't have to disassemble the whole thing. But of course there was a single rusted bolt keeping me from doing that so these pictures are the best I can do until I have time to dissemble it.

The best bet as you already mentioned, is call and talk to someone at a company that knows about this transformer. However, if the company is either no longer in business or no one still has knowledge of this system, then maybe testing is a possible method.

Certainly looks like it was rigged for a specific voltage output (at what frequency is a question I do not know how to address); one could test to see what the x-former does if a very low AC voltage is applied. Might need to be under oil, however, to protect the transformer. Not that I am saying these are the only courses of action. I am sure others will have more ideas.

Multi-kiloamp pulses are fairly easy to obtain and do not require much power input to produce, provided one knows what they are doing and has instruments in hand capable of measuring the pulse. The secret is in a low impedance source for voltage and ultra-low inductance in the circuit that the pulse occurs in.

It is all about watt-seconds (joules). If I charge a capacitor to 10kv and shunt it into a 10 ohm impeadance and that pulse produces 1,000 amps of peak measured current for 1 micro-second, then assuming the voltage stayed up throughout the pulse, (big assumption), the result is a 10 megawatt peak power blast. How many joules or watt-seconds is that? .......it is 10 real watts. Due to losses you might have had to put as much a 100 watts of real power into the capacitor. Thus, high currents that boggle the mind are easy to obtain with less than 100 watts of input. When I say easy, it is easy to folks who know about such things, just like fusion is easy to do by folks who know about such things.

I knew a fellow engineer who used to say that microwaves and pulsed power systems, at the engineering, level showed little differentiation between its successful implimentation and black magic.

Richard Hull

I think I actually have the correct transformer for that thyratron lying around someplace. You also need to supply power to the reservoir heater as well.

I pulled one out of an old excimer laser for LASIK.

I see what the 130 kV x-former can be used for, but what does one do with such a massive thyratron?!

One uses the thyratron to switch mega-watt pulses. Obviously critically needed in whatever this Universal Voltronics system was given birth to do.

Thyratrons of this ilk are built to "take it on the chin". No glass jaws here. If you go shopping for one of these, new, just the tube will be between 1 and 2 kilobucks. Be prepared for feed a reservoir voltage of 2-6 volts with 10 amps and a filament of 6-10 volts with ~20 amps. In smaller 500 kilo-watt, glass thyratrons, the reservoir was usually in parallel with the filament, needing only a single high current, low voltage Xfrmr.

Richard Hull

Am I wrong or that thyratron has a bent pin?

The HTR and RES pins were both a little bent. Luckily the vent port wasn't bent or the D2 magic could have leaked out. The device is heavy so I think people picking it up would end up pressing against the pins causing them to bend.

John

A crack in any of the ceramic-metal seals would impair the hermeticity.

That's good point. I was thinking along the lines of the vent tube being punctured/cracked.
The 'pins' you see are more of a terminal block that fit over the actual pin and have a set screw to attach to the pin. I'll remove it tonight and do a closer inspection.

The thyratron had a little ceramic chipped away by the pins but it doesn't look deep enough to be a problem.

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I got this Xray transformer earlier in the year off of Craigslist. The dentist even gave it to me for free when I told her it was for my electronics hobby.
I don't see any voltage/current specs. Does anyone have an educated guess in what they might be?

The inside of the spark gap transformer only had a transformer in it. It was already drained of oil.
I suppose the instructions on the case were for whatever system/unit it was part of.