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Todays surplus gloat!

PostPosted: Sat Sep 11, 2010 8:09 pm
by Jerry
Went down to R5-D3 surplus here in Portland. Hadnt been down there in a few months and was looking for a couple odd ball connectors. Well, he didnt have them, but I found other goodies!

Sargent Welch Bench lamp working torch, $5
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Sargent welch torch by macona, on Flickr
X-ray bridge rectifier, 19 H463 diodes in series each side and some nice teflon core rg-142 coax, that stuff will handle at least 2kw at lower freqs. The diodes are good for at least 7kv each at 220ma, possibly 9kv but there is no -3 or -5 to tell which. Now I just need a tank of oil! Paid $5 for all of it.

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X-ray bridge rectifier by macona, on Flickr

Last but not least, a bunch of nixies and a couple dekatrons. 28 of the larger NL-846 and 8 smaller Wang 140-0011. All appear to be brand new. Also two Sylvania 6802 Dekatrons. I smell a nixie clock! ;) Also got, not pictured was a little 1c21 gas discharge triode and a couple pairs of plato electronics dikes. $20 for all of that.

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Nixie tubes and dekatrons by macona, on Flickr

Re: Todays surplus gloat!

PostPosted: Sat Sep 11, 2010 9:39 pm
by Doug Coulter
Great score! Bill had gotten us a very similar torch, but with no labeling, and I never got around to firing it -- so that pic is useful, thanks -- now I know how to hook it up (if I can find it again).
And that it's meant for oxygen...I've had bad experience with using pure O2 in things that aren't meant for that...(too much mixed volume == boom!)

We've had good luck using plain old mineral oil (got ours from McMaster) for things like that bridge. At least it starts out clean...

Joe Sousa would probably have some interesting words about those nixies and dekatrons -- right up his alley. I'll send him a link and see if he'll respond here.
You should check out http://www.coultersmithing.com/data/DataSheets/Neon/ ... the two books by Baum and Phillips cover some very cool tricks with these things.

Re: Todays surplus gloat!

PostPosted: Sun Sep 12, 2010 9:56 pm
by Joe Sousa
At least some of the nixies look like they came from equipment. Perhaps they were salvaged from the trash heap.

A few years ago I built a voltage clock and a resistance clock.

That is, the voltage clock puts out a voltage that will look like time when read by a voltmeter. For example at 12:30, 12.3V is fed to the voltmeter, which is set for a scale that shows two decimal places. This was built with CD4000 logic a DAC and and opamps. The down-side of this design is that it burns more power than button cells can provide for a long time.

The Resistance clock puts out a variable resistance that is scaled to read 12.3KOhms at 12:30. The reading ohm-meter is set to a fixed KOhm scale with two decimal places. This design also uses CD4000 logic and a binarily weighed string of resistors that is shorted selectively, according to the desired output resistance/time. This design only draws power into the CD4000 logic so it runs for about a year on two lithium button cells.

The whole reason for these clocks is to encourage the preservation of the nixies in their original Voltmeter or Ohm-meter application. These are also easier to build because you don't need a fancy display case.

I managed to convince my coworker Bill Walter to make a PIC version of the resistance clock and one that is a frequency clock. The Frequency clock is meant to show the time on conventional frequency counters. He made some very nicely laid out PCB's and even tested them out among friends. He meant to put these on the market, but has not gotten around to it yet. Bill's designs can be built in an evening because there are few parts. These clocks run off batteries. Hopefully, Bill will put these on the market soon.

I haven't played with nixies or neon in a while. Have been having a lot of fun with old tube radios, and designing tube radio circuits. The one neon project that has been shelved is an all-neon clock with just two-legged neons, R's C's. No diodes. I designed and built a robust binary counter and figured out how to turn 60Hz into a 1s timebase. Maybe when I run out of tube radio circuit designs.
-Joe

Re: Todays surplus gloat!

PostPosted: Mon Sep 13, 2010 5:29 am
by Jerry
Best I can tell all the nixies are new. The smaller ones have never been soldered to a board and there is no marks on the pins from a socket. Also none of the tube have any of the sputtering or discoloration I have seen in used nixies. They are all perfect and identical. It would not surprise me that the place I got them from had some new tubes found someplace. A good chunk of his sales is tubes and even though he does not have an internet presence he does good sales.

There have been a lot of guys turning old electronic equipment into clocks lately. A lot of people are using arduinos since they are so easy to program. One guy even makes a nixie shield board that will drive up to 80 elements multiplexed off one board. It looks like they use the 74141 driver which are all over ebay, although from russia.

Thinking 6 of the larger tube for time, 6 smaller for date, and a dekatron spinning for seconds. But who knows when I will get to that. I still got to work on my laser cutter, which I am making progress on the boards for.