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Circuit/motherboard for vacuum tubes?

Last response: in CPUs
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July 5, 2010 3:05:37 AM

I want to test something that has to do with cpu design, and i need a very basic start for it. I know you can buy vacuum tubes, but i was wondering if theres a special circuit board to plug them into you can buy that is also programmable.
a c 131 à CPUs
a b V Motherboard
July 5, 2010 4:28:42 AM

programmable? Are you looking for a PIC? Because that's not the same as a circuit board.
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July 5, 2010 4:54:07 AM

You need to supply more information. What you are asking for is very unusual. Vacuum tubes are rare and expensive these days. Unless you are going retro or doing extreme high frequency or power there is not a need for them. You are probably looking at a lot of money or time building it yourself.
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July 5, 2010 8:25:03 AM

Yes... kind of like a PIC. But i need vacuum tubes because this thing im doing has to do with computer architecture at a very basic level. And im also going to be physically modifying the tubes. I want to know where to buy a board to plug the tubes into.
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a c 172 à CPUs
a c 156 V Motherboard
July 5, 2010 10:20:26 AM

This is the only time that I know that someone used a vacuum tube in a motherboard:
http://www.neoseeker.com/Articles/Hardware/Reviews/aope...

And what do you mean: "physically modifying the tubes"?

And last, if you want to something "very basic" with CPU design, I suggest SSI (Small Scale Integration) using 74XX series IC chips.
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a b à CPUs
July 5, 2010 2:27:39 PM

I once saw an AM car radio from the late '50s or maybe '60s that used miniature vacuum tubes with wire leads soldered to a chassis, along with various discrete resistors, capacitors, coils, etc. Dunno what kind of voltage they required but I'd bet more than the standard automotive 12V. Probably some kind of DC-DC converter since IIRC most vacuum tubes require a "plate" voltage of a couple hundred volts of well-filtered DC. Good way to electrocute yourself if you don't know what you're doing :p .

Also soldered connections don't make for a particularly programmable circuit board, unless you are very patient & skilled with a soldering gun :p .
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July 5, 2010 5:45:24 PM

jsc said:
And last, if you want to something "very basic" with CPU design, I suggest SSI (Small Scale Integration) using 74XX series IC chips.


No doubt, build a cpu one gate at a time.
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July 6, 2010 5:00:11 AM

I'm really curious now. If this isn't top secret would you explain more.
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Anonymous
a b à CPUs
July 6, 2010 12:54:34 PM

@jsc

man you come up with some real obscure links in your replies sometimes, where the heck does all this info come from you must have a head the size of a melon to hold all that info in your brain

Seriously +1 Respect...

OP, I am really curious, what exactly are you trying to create? heck if you want basic computing, why vacuum tubes, go all the way back and use punch cards!

If its cpu design, can you not look at software that would replicate what you are trying to do

http://www.educypedia.be/electronics/easoftsim.htm

Good place to look for Electrical CAD software

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July 6, 2010 3:36:46 PM

turk_1000 said:
I'm really curious now. If this isn't top secret would you explain more.


http://en.wikipedia.org/wiki/7400_series

All computers are a set of on/off switches. In it's most basic state the only answer a computer can give is either yes/on or no/off. There are many modifiers, (are you connected to the internet, yes, are you on the webpage I want, yes, is it on the screen now, yes, you get the idea...) but that's what it boils down to.

A logic gate performs a logical operation on one or more logic inputs and produces a single logic output. That output is yes/on/5v or no/off/0v. It would take millions of 7400 chips taking up probably an entire building to simulate a CPU chip.
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a c 131 à CPUs
a b V Motherboard
July 6, 2010 3:59:31 PM

The intel 4004 contained 2250 transistors. Already we are not in the millions. Now, each 7400 series chip contains 4 gates. Each gate contains at least 2 transistors (I am not sure the number, likely it is more) 2250/8= 282 chips.
Of course no one can reasonably simulate an i7, but older CPUs are more than possible. I believe you can actually get a kit to build your own (I think it was an 8086) about the size of a desktop cube. They even include adapters so if you have an old motherboard, you can plug it in. I want one of those, it would be cool.
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July 6, 2010 7:18:09 PM

Well are any of you familiar with those pretty large transistors that they use in college physics labs and some engineering labs? Well now im interested in those since they are large enough to be physically manipulated. Thats why i was interested in vacuum tubes. If anyone knows where to find such transistors and a basic board to plug them into (dont care if its only programmable by physically changing the board) i would be very appreciative. The budget shouldn't be a problem.

Also if you want to know what im doing just wait.
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