Title: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: WBear2GCR on April 29, 2017, 11:34:13 PM Ok, so this strapping supply followed me home.
Very low price, from NYS auctions. My tax $$ coming back. The main warehouse is 1/2mi from here. On occasion there is good stuff to be had. It takes 208vac single phase the entire box is rated at 30 amps! some of these PS units apparently powered up a 3CX3000 tube... no idea what this one was running. No solid documentation could be found online. Thermal Jarrell Ash is the mfr... never heard of them. ... of course I don't know what the HV voltage is, and will have to do an actual check of the iron and the B+ (if I can), the whole PS may have an enable link from the main unit. The cabinet is very well built, sitting on casters and made of what looks like 0.20" aluminum. It has a neat top/front cover, and a side that lifts out (shown removed in the pix). So, what to DO with this?? Title: Re: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: KD6VXI on April 30, 2017, 11:30:35 AM Bear,
I've not seen THAT one before, but they did power some largish tubes. 8877 power supply is 4kv at point 8 amps. 3k supply is 4kv at an amp I've seen plasma therm boxes with tens and fifteen as well. They are some of the bigger rf gennies. --Shane KD6VXI Title: Re: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: WA2SQQ on May 01, 2017, 08:35:54 AM One of my other pass times is stained glass. In the beginning I'd buy glass for a project. Now, I buy glass and decide what I can make with it. You have a great power supply - time to build an amp or at least a nice transmitter!
Title: Now what! Arrghh! Post by: WBear2GCR on May 01, 2017, 07:55:04 PM Got the spec from the xfmr mfr... ...not so good. Not bad, but not what I had hoped for. Specs: 3.2KVA Input: 200/208/220/240V Output: 1620V So, ~2290vdc with a full wave bridge, cap input. Probably could get ~>2500 by using the 200 tap on 240vac. But I had hoped for a higher B+, in the >3500 range, more like the mid 4kv... So, NOW WHAT?? _-_- Title: Re: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: Opcom on May 02, 2017, 12:12:05 AM five 3-500Z.
@400mA each. 500-600W each at 2000-2500V so. plate C might be a problem at some point but I saw an 11m amp with 10 of those tubes in it once so there is the 10M band in theory anyway. two 3-1000.. Title: Re: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: WBear2GCR on May 02, 2017, 08:17:50 AM I have never laid eyes on a 3-1000. Besides it would like more B+ to sing. 2500v is even low for 3-500s... :( Might be a nice bit of iron for a quad of 813s... ...but not what I had in mind when I saw it. Good thing is was cheap!!! :) _-_-bear Title: Re: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: W3RSW on May 02, 2017, 12:45:21 PM Perfect for a quad of 3CX800A7's if you can afford them. ;D
Or with a full wave voltage doubler and at 3.2kva you've got your B+ for an 8877 or a light 3CX3000A7. You know that the doubler only takes a couple of diode strings, don'cha? Title: Re: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: KB2WIG on May 02, 2017, 04:56:50 PM A few caps and diodes and you have a nice Jacob's Ladder It keeps most of the neighbors away. klc Title: Re: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: W2PFY on May 02, 2017, 05:50:07 PM Quote I have never laid eyes on a 3-1000. Besides it would like more B+ to sing. 3-1000's like 3 KV but would probably run on less and still do a good job. Just last week I saw two of them on eBay and they wanted about 3000 each fer them? You could run a big rig with eight 813's in push pull parallel 4 in the mod and four in the final? Now that the CB rules have changed you can now shoot skip on there. I didn't see anything about power rules on the FCC's latest change? Running eight 813's on the CB band would also be a good way to meet your neighbors as well? Title: Re: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: W2PFY on May 02, 2017, 05:54:51 PM Quote But I had hoped for a higher B+, in the >3500 range, more like the mid 4kv... Build an external PS with a bridge rectifier that would give you the 1000 volts you need in series with that unit? Title: Re: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: Opcom on May 02, 2017, 10:08:00 PM How about those Russian types? Any of them do well on 2000-2500V?
Question is, what tube if any did this beast power? I had no idea plasma spectrography required that much juice. learn something new every day. tabulated 3-500z data. just convenient.. Old from when re-doing Tucker's modulator. Title: Re: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: WBear2GCR on May 02, 2017, 10:31:29 PM I have no clue what THIS power supply actually ran as far as tubes...
I did see one example that used a single 3CX3000, but that's not this one, afaik. The doubler idea was mentioned to me by a non-ham friend. Good idea. Not sure how much umph it will deliver... but this is a 3200VA hunk-a-hunk of burnin' iron. So what are we talkin' here half? or 1500watts?? 813s are certainly possible. But it seems like a waste to use a 3.2kva iron to run 4 x 813s... I tend to not like to run modulators off the same iron as the RF, but I suppose that might be ok. But do I want an 813 rig? Looks like this one might be made into parts... :( Title: Re: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: KD6VXI on May 02, 2017, 11:33:36 PM In rf generators I've seen:
3cx1000 3cx1500 3cx3000 3cx10000 3cx15000 4-65 4-125 4-400 4-1000 5cx1500 Thats what was popular from Henry, and they made generators for a bunch of people (Anelva, Perkins Elmer, ETC) . BUT, being Henry is Los Angeles, we saw a TON more of them vs the other manufacturers come surplus time. The 3cx1000 likes 3kv.. And it has a bigger grid than the 8877. And it's rebuild able. And it's available surplus all around ebay, since it was used in TV translators. Hope that might help. And when going to a doubler, your KVA remains the same. Current drops by half. No free lunch, it's a legal limit plus us a little bit maybe, power supply. In the press release, you are still limited to 4 watts carrier and 12 pep on CB. The big change was the abolish meant of the 150 mile rule. --Shane KD6VXI Title: Re: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: KD6VXI on May 02, 2017, 11:38:47 PM The only Russian tubes you might want to explore (off the top of my head) would be the gi 46 and gi 7b. They really wake up between 2.5 and 3kv. Probably be ideal, honestly....
Close to the same tube electrically, the 46 has a newer style cooler, takes a real blower and has a bigger grid. Not so sure about sockets. I roll my own collets, etc. Amazing what you find in old fuse boxes, etc that can be repoirposed.... AC0C did a GI7 project out of an sb200. It's a screamer. --Shane KD6VXI --Shane KD6VXI Title: Re: Do WHAT with this Plasma Spectrogarph Power supply?? Post by: Opcom on May 02, 2017, 11:42:56 PM well besides the parts you got a nice case to build something in. The JAWS II 3CX3000 amp uses a similar power supply (http://amfone.net/Amforum/index.php?topic=16823.msg122645#msg122645) cabinet but lower KVA and a doubler and it's best for SSB use. I don't use that amp due to no AM-ready tuner at the moment. It would be OK on AM for legal limit having a 2.7KVA 18 Ohm secondary oil filled transformer but was built to do high PEP on SSB. I could join the slopbuckit army I guess! My point is that you could do AM with a doubler and 3CX3000 if you did not mind the voltage regulation issues compressing the signal a little. What is the DC resistance of the secondary of that transformer? Lots of options are open, don't give up on it yet! AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
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