Yes, this was Bletchley, too.
They even had it stolen a few years ago:
BBC News | ENGLAND | Paxman returns Enigma machine
Almost every year there is a fellow from New Jersey that collects enigma machines and shows them off at Dayton. Did you see him as you walked around? Can't remember his name (Tom?) but he has quite the collection of them. He makes trips to Germany just to find them.
Tectronix Type 585A;
1963 to 1972; weight: 37 Kg / 80 lbs; power consumption: 630 Watt.
Tube count: over 80; no less than 15 6DJ8's in the vertical amp, 85 MHz.
among them: 6AL5 6AU5 6AU6 6CL6 6CY5 6DJ8 6EW6 12AL5 12AU6 12AU7 12AX7 12B4 5651 5642 6080 7788.
Operational Amplifiers:
Long before the uA702 opamp IC, vacuum tube based op-amps were already used in the industry (and military) in analog computers and controls.
The Philbrick K2-W used two 12AX7 around 1953.
The later K2-XA had a 12AX7 / 7025 plus a 6BQ8A / 6CL8A (plus 2 neons plus a single npn transistor NS716)
1963 to 1972; weight: 37 Kg / 80 lbs; power consumption: 630 Watt.
Tube count: over 80; no less than 15 6DJ8's in the vertical amp, 85 MHz.
among them: 6AL5 6AU5 6AU6 6CL6 6CY5 6DJ8 6EW6 12AL5 12AU6 12AU7 12AX7 12B4 5651 5642 6080 7788.
Operational Amplifiers:
Long before the uA702 opamp IC, vacuum tube based op-amps were already used in the industry (and military) in analog computers and controls.
The Philbrick K2-W used two 12AX7 around 1953.
The later K2-XA had a 12AX7 / 7025 plus a 6BQ8A / 6CL8A (plus 2 neons plus a single npn transistor NS716)
That was a great scope in it's day. I have one resting comfortably in my basement along with a 547. They were my prized scopes back in the 70's and I paid a lot for them back then. Just can't get rid of these old pals.
The last two years I was selling stuff in the swap meet and didn't have time to wander around. Good thing since i have no place to keep "stuff" anymore.
Some used 8068's which seems to be a high priced 6CD6.
The 5 series used a "distributed amplifier". This is a pair of matching delay lines (the delrin rods with coils wound on them) with multiple taps and an amplifier stage wired between each pair of taps. All stages operate in parallel. This allows a wide bandwidth with equal delay characteristics for all frequencies. The same technology is used today in microwave IC design to make broad band RF power amp IC's. The Freescale MW7IC008NT1 is an example.
Heathkit made a HV Regulated power supply with 6L6s as regulator pass elements. I'm sure there were hundreds of similar designs in every electronics lab in the US, not to mention the rest of the world.
I once saw a HV power supply that used 2A3s as pass elements. I didn't think anything of it (back in the early 70s) as almost everything I saw surplus was tube based.
A Neon Sign company that I bought supplies to build a He-Ne laser from had an induction heater that they used to activate the getters in sign tubes with. I know it was tube based but I never looked close to see what was in it.
I once saw a HV power supply that used 2A3s as pass elements. I didn't think anything of it (back in the early 70s) as almost everything I saw surplus was tube based.
A Neon Sign company that I bought supplies to build a He-Ne laser from had an induction heater that they used to activate the getters in sign tubes with. I know it was tube based but I never looked close to see what was in it.
Every major test equipment company made one or two. They all used the same schematic. I had about 5 at one time. There are two kinds, one has two 6L6GC's and makes 100 mA, the other has 4 6L6GC's and makes 200 Ma. I kept a Knight KG664 (Allied Electronics) because it is the 4 tube variety.
I have a Fluke 407D which goes up to 555 volts at 300mA. I have had the meter pegged sucking about 500 mA out of this thing without complaint. It uses 5 X 807's for pass tubes.
View attachment 374465
There were very few if any power pentodes in the Enigma machine. The rectifiers would most likely have been mercury arc types. The pentodes it did have in it were almost all CV358s and the rebuild was done with mainly the civilian EF37A as a replacement.
I found one with damaged shielding and polished it up for a shot at the internal construction with a camera
I have a feeling that the guy may have been trawling for audio valves. This could be checked by looking at what other projects he has been working on.
There were very few if any power pentodes in the Enigma machine. The rectifiers would most likely have been mercury arc types. The pentodes it did have in it were almost all CV358s and the rebuild was done with mainly the civilian EF37A as a replacement.
I found one with damaged shielding and polished it up for a shot at the internal construction with a camera
I have a feeling that the guy may have been trawling for audio valves. This could be checked by looking at what other projects he has been working on.
Attachments
It is a 6DQ6-B beam tetrode and I have not bothered to trace out the circuit as it is very simple and would be easy to follow in the event of a fault.
Okay, so here is a long story that ties this tubes and industrial equipment and diyaudio to me personally. I have everyone here to thank for adding to my education and interests.
I recall back in my university days visiting my geeky girl friend's boyfriend in his physics lab and they had a small corner dedicated to older laser equipment. I am talking old stuff and this was in stark contrast to my Chemistry labs where everything that was new was there and anything remotely old was tossed***. I thought it was a mini-museum of sorts, but he said it was all functional and they used it when they needed something, otherwise it would just sit there. A lot of it looked custom made, but one thing struck me as interesting and funny looking.
It was a mix of components on a flat open metal chassis with one large grayed out old tube connected by a socketed plug to another equally old metal chassis with a large new electrolytic can cap, a bunch of vacuum tubes, wires criss-crossing here and there, an overly large inductor taking up most of the space (it was labelled, "CAUTION -- INDUCTOR" for some reason), mounted with a mix of old and new screws, old square(!) and new hex nuts, switches, and fabric insulated wiring. It looked like it was cobbled together and to make it look like it was serious, there were a multitude of stickers warning of laser radiation. I thought it was a joke of some sorts, so naturally I asked about it.
Turns out it wasn't a joke at all, but a powerful but small Argon laser that would have been very expensive if bought new. Story was one of the dead professors had brought this with him when he was poached to work at the university long ago and it remained there ever since, as a work horse. This thing had been fixed many times (most recently by my friend's boyfriend who had replaced the can capacitor) and used many, many times.
Talking about it, he said he wasn't sure about the circuit ("but it works great!"), there was no documentation only notes from previous grad students and profs, but knew that the vacuum tubes were there to start the whole gas ionization/excitement of the Argon in the long gray tube. It required kid gloves because of the lack of documentation, no replacement for the original vacuum tubes (they were not sure what tubes they were since the numbers were all rubbed out and even if knew the tube number, they were not sure if there were any more tubes available as this was back in 1991, so kind of infancy of the internet).
At the time, to me it was dangerous because the laser power source was all very cool but very dangerous because it still had the original two pronged plug (no ground? what kind of sorcery is this?).
But only now after being part of the diyaudio tube community do I now realize the true danger of that laser set-up... the power source referenced the AC outlet directly because there was no transformer at all.
They sure did build equipment differently back then.
*** the amount of stuff that had vacuum tubes that was labelled free after the "garage sale" of equipment in the summer (why the heck would they hold summer garage sales when students were far and few between?) was huge. If I had any brains there at the end of the sale, my father's van would be filled with vacuum tube stuff, old scopes, hp voltmeters/timers/boxes with rectangle buttons, and heavy old chassis's that I never would ever use or thought as "junk".
I recall back in my university days visiting my geeky girl friend's boyfriend in his physics lab and they had a small corner dedicated to older laser equipment. I am talking old stuff and this was in stark contrast to my Chemistry labs where everything that was new was there and anything remotely old was tossed***. I thought it was a mini-museum of sorts, but he said it was all functional and they used it when they needed something, otherwise it would just sit there. A lot of it looked custom made, but one thing struck me as interesting and funny looking.
It was a mix of components on a flat open metal chassis with one large grayed out old tube connected by a socketed plug to another equally old metal chassis with a large new electrolytic can cap, a bunch of vacuum tubes, wires criss-crossing here and there, an overly large inductor taking up most of the space (it was labelled, "CAUTION -- INDUCTOR" for some reason), mounted with a mix of old and new screws, old square(!) and new hex nuts, switches, and fabric insulated wiring. It looked like it was cobbled together and to make it look like it was serious, there were a multitude of stickers warning of laser radiation. I thought it was a joke of some sorts, so naturally I asked about it.
Turns out it wasn't a joke at all, but a powerful but small Argon laser that would have been very expensive if bought new. Story was one of the dead professors had brought this with him when he was poached to work at the university long ago and it remained there ever since, as a work horse. This thing had been fixed many times (most recently by my friend's boyfriend who had replaced the can capacitor) and used many, many times.
Talking about it, he said he wasn't sure about the circuit ("but it works great!"), there was no documentation only notes from previous grad students and profs, but knew that the vacuum tubes were there to start the whole gas ionization/excitement of the Argon in the long gray tube. It required kid gloves because of the lack of documentation, no replacement for the original vacuum tubes (they were not sure what tubes they were since the numbers were all rubbed out and even if knew the tube number, they were not sure if there were any more tubes available as this was back in 1991, so kind of infancy of the internet).
At the time, to me it was dangerous because the laser power source was all very cool but very dangerous because it still had the original two pronged plug (no ground? what kind of sorcery is this?).
But only now after being part of the diyaudio tube community do I now realize the true danger of that laser set-up... the power source referenced the AC outlet directly because there was no transformer at all.
They sure did build equipment differently back then.
*** the amount of stuff that had vacuum tubes that was labelled free after the "garage sale" of equipment in the summer (why the heck would they hold summer garage sales when students were far and few between?) was huge. If I had any brains there at the end of the sale, my father's van would be filled with vacuum tube stuff, old scopes, hp voltmeters/timers/boxes with rectangle buttons, and heavy old chassis's that I never would ever use or thought as "junk".
At the risk of exposing myself as a silly old fart, I still think it is instructive to remind people that the transistor was invented in 1948 - that is, the ganky, lashed-up point contact POS that demonstrated the concept. The real deal (as usual) took 5-10 years to emerge, even in its original cranky. creaky, leaky Ge incarnation. If you wanted to lash circuits together in the 30's, 40's and 50's, and early 60's, the bits you lashed together were made of glass and glowed.
The first ones were so hideous that they included access holes so's you could wiggle the point contacts around just to get the things working. By letting in dust and moisture, any surviving examples probably don't work at all.
It's miraculous that they didn't just figure "T'hellwiddit! No future for this".
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