EEVblog Electronics Community Forum

General => General Chat => Topic started by: Sionyn on May 23, 2012, 09:29:56 pm

Title: Return of the Vacuum Tube
Post by: Sionyn on May 23, 2012, 09:29:56 pm
is this thing serious i mean sure they have their uses but a return so how i don't think so
i'll never forget my grandad's reaction when even i mentioned vales 'damn valves'
http://news.sciencemag.org/sciencenow/2012/05/return-of-the-vacuum-tube.html?ref=hp (http://news.sciencemag.org/sciencenow/2012/05/return-of-the-vacuum-tube.html?ref=hp)
Title: Re: Return of the Vacuum Tube
Post by: PA0PBZ on May 23, 2012, 10:02:58 pm
Well, it's not really a vacuum tube is it? It has no vacuum and it has no glass. The only thing simular to a vacuum tube I can see is that the electrons travel freely, not in silicon or some other material. And yes, radiation resistance is a good thing to have, so it looks serious to me.
Title: Re: Return of the Vacuum Tube
Post by: Time on May 23, 2012, 11:27:37 pm
Boasting operating frequencies of .46 THz I would say its pretty serious.  Its nano sized in a substrate.  I would say this is nothing like grandpas old valves.
Title: Re: Return of the Vacuum Tube
Post by: kaptain_zero on May 23, 2012, 11:45:50 pm
I've always felt that, much like "smokeless gunpowder", solid state electronics were but a passing fad. Even today, without the nano stuff entering into the picture... when you want REAL rf power, it's glow in the dark technology to the rescue.

Regards

Kaptain "RetroGrouch" Zero 
Title: Re: Return of the Vacuum Tube
Post by: vk6zgo on May 24, 2012, 12:22:36 am
I too, like "FETs with a fire in 'em"---but it looks like they've taken the "fire" away with these new "nano" thingys! ;D
Title: Re: Return of the Vacuum Tube
Post by: codeboy2k on May 24, 2012, 01:19:19 am
something like this is very useful, although at 150nm it's large compared to today's features at 22nm and upcoming 16nm.

The article quotes an engineer stating that it's not compatible with today's voltages, and that's true, but I don't see that as a problem. In the past we had 5V, 3.3V, 1.8V, and now 1.2V tech, and even 0.8V; the only reasons we keep lowering the voltages is to allow the gates to switch faster and to reduce the heat generated due to resistive losses in the silicon.  At 10V and crossing a 160nm gap, this technology doesn't have much resistance in air, and so I think very little heat would be generated due to resistive losses.  And if they can improve the technology to reduce the gap size, then the voltages needed to cross that gap can be reduced, and resistance would be reduced even further still.

If this tech goes mainstream, we would just move back to a higher voltage supply, but the advantage would be way faster computing at .46THz (460Ghz).  That's 2 orders of magnitude faster than we can currently achieve with silicon.





Title: Re: Return of the Vacuum Tube
Post by: CyberWalker on May 24, 2012, 10:36:45 am
I agree with kaptain_zero!   ::)
Title: Re: Return of the Vacuum Tube
Post by: ejeffrey on May 24, 2012, 02:38:34 pm
Well, it's not really a vacuum tube is it? It has no vacuum and it has no glass. The only thing simular to a vacuum tube I can see is that the electrons travel freely, not in silicon or some other material.

It pretty much is exactly a vacuum tube.  Actually, it has roughly the same amount of air as a traditional vacuum tube -- just in a volume 15 orders of magnitude smaller.
Title: Re: Return of the Vacuum Tube
Post by: PA0PBZ on May 24, 2012, 11:02:10 pm
It pretty much is exactly a vacuum tube.  Actually, it has roughly the same amount of air as a traditional vacuum tube -- just in a volume 15 orders of magnitude smaller.

Ok, can't argue with that  8)
Title: Re: Return of the Vacuum Tube
Post by: obiwanjacobi on May 25, 2012, 01:37:34 pm
What a wonderful development! Who cares how it works or what its called, as long as it works and at 460 Ghz I would say it is very useful.

I'm also thinking hybrids: pieces of a die based on current technology (16nm you say! wowzers) and parts of the die working at this new technology. I mean, the rest of the PC is not going to get near that speed anyway (although memory with a 460 Ghz bus would be awesome).
Title: Re: Return of the Vacuum Tube
Post by: Simon on May 25, 2012, 01:46:48 pm
I think you meant GHz where you put MHz  ;D. I'm not sure of the claim about a valve computer being faster though. As each valve is a huge switch and you need billions of switches to make a processor that makes for a huge device and lots of long connections with bye bye to the speed. Obviously these things will have their uses.
Title: Re: Return of the Vacuum Tube
Post by: obiwanjacobi on May 25, 2012, 02:18:46 pm
I think you meant GHz where you put MHz  ;D.

Hi hi, yes. I changed it now.
Title: Re: Return of the Vacuum Tube
Post by: T4P on May 25, 2012, 02:46:20 pm
No, Just no.

(http://alltheragefaces.com/img/faces/jpg/angry-no.jpg)
Title: Re: Return of the Vacuum Tube
Post by: Ed.Kloonk on May 25, 2012, 02:49:35 pm
I have to say when I saw the new nutter making those x-ray tubes, my appreacitaion of tubes has changed. To see someone construct a tube with more or less tools I have here makes me more interested than a boring old silicone diode I wouldn't know where to start on how to construct.

Title: Re: Return of the Vacuum Tube
Post by: Dawn on May 29, 2012, 10:55:08 pm
I never heard of the manufacturer, but I wonder about the company's origin. Many years ago I read about a Soviet era MIG teardown that had been conveniently delivered by a defector. One of the surprising finds was the extensive use of what was referred to as miniature, low voltage, vaccum tubes that apparently were a very small, board mounted component. Resistance to EMP and ruggedness was cited at the most probable reason that they chose to use them in a relatively new 80's design. I wonder if these are the outgrowth of that technology?
Title: Re: Return of the Vacuum Tube
Post by: tom66 on May 29, 2012, 11:18:42 pm
Looks interesting, but the 460 GHz is only theoretical. If they can produce a practical device capable of even a tenth of that I will be impressed. I also wonder what power consumption is. With a typical vacuum tube it's pretty high because the filament must be kept warm all the time (constant stream of electrons); does this device require a constant stream of electrons to work?
Title: Re: Return of the Vacuum Tube
Post by: NiHaoMike on May 30, 2012, 02:22:10 am
Looks interesting, but the 460 GHz is only theoretical. If they can produce a practical device capable of even a tenth of that I will be impressed. I also wonder what power consumption is. With a typical vacuum tube it's pretty high because the filament must be kept warm all the time (constant stream of electrons); does this device require a constant stream of electrons to work?
It uses field emission or something like that. I can see those nanoscale vacuum tubes being quite useful for RF and communications circuits.

BTW, tubes are still in common use. A lot of modern automobile dashboards are plasma displays. I'm guessing it has to do with plasma displays being far more tolerant of extreme temperatures, but LCDs are also very common in cars, so I'm not so sure on that. Even stranger is that while my new car (a 2011 Prius) uses plasma for the dashboard, the radio and A/C both use LCDs.
Title: Re: Return of the Vacuum Tube
Post by: T4P on May 30, 2012, 03:47:59 am
But those aren't tubes okay  :)
Title: Re: Return of the Vacuum Tube
Post by: tom66 on May 30, 2012, 12:31:24 pm
Looks interesting, but the 460 GHz is only theoretical. If they can produce a practical device capable of even a tenth of that I will be impressed. I also wonder what power consumption is. With a typical vacuum tube it's pretty high because the filament must be kept warm all the time (constant stream of electrons); does this device require a constant stream of electrons to work?
It uses field emission or something like that. I can see those nanoscale vacuum tubes being quite useful for RF and communications circuits.

BTW, tubes are still in common use. A lot of modern automobile dashboards are plasma displays. I'm guessing it has to do with plasma displays being far more tolerant of extreme temperatures, but LCDs are also very common in cars, so I'm not so sure on that. Even stranger is that while my new car (a 2011 Prius) uses plasma for the dashboard, the radio and A/C both use LCDs.

They're probably VFD displays, not plasma displays. VFD works on lower voltages (~10V); plasma displays require complex sustain/address waveforms and 60V/200V supplies.
Title: Re: Return of the Vacuum Tube
Post by: SeanB on May 30, 2012, 03:28:32 pm
VFD units are true vacuum tubes. Directly heated cathode, control grid in the electron flow and a segmented anode complete with electron activated phosphor as a display medium. I think you could use one as a triode with a little care in design.
Title: Re: Return of the Vacuum Tube
Post by: free_electron on May 30, 2012, 03:42:26 pm
vacuum tubes (thermionic valves) sound really good ... especially when you hit them with a hammer and they go pling , kling , plong , klak.
Title: Re: Return of the Vacuum Tube
Post by: T4P on May 30, 2012, 03:52:23 pm
vacuum tubes (thermionic valves) sound really good ... especially when you hit them with a hammer and they go pling , kling , plong , klak.

free_electron, small wonder why you are my god here, i entirely agree with you on every single level
Title: Re: Return of the Vacuum Tube
Post by: G7PSK on May 30, 2012, 04:26:15 pm
vacuum tubes (thermionic valves) sound really good ... especially when you hit them with a hammer and they go pling , kling , plong , klak.

Not when you have stainless steel ones.
Title: Re: Return of the Vacuum Tube
Post by: free_electron on May 30, 2012, 04:37:41 pm
for steel ones : use bigger hammer
Title: Re: Return of the Vacuum Tube
Post by: SeanB on May 30, 2012, 06:01:03 pm
Ok, we will take the nice digital camera, and have them running in a high radiation area ( 100 G/H) along with a Vidicon and valve based camera. Which one will still be working in 5 minutes without any problems, and which one will still be running a year later.

Now guess why there are no nuclear clean-up robots.
Title: Re: Return of the Vacuum Tube
Post by: T4P on May 30, 2012, 06:11:24 pm
Ok, we will take the nice digital camera, and have them running in a high radiation area ( 100 G/H) along with a Vidicon and valve based camera. Which one will still be working in 5 minutes without any problems, and which one will still be running a year later.

Now guess why there are no nuclear clean-up robots.

Oh, a 100sqfm relics of a dinosaur age camera you mean ?
Title: Re: Return of the Vacuum Tube
Post by: SeanB on May 30, 2012, 08:54:48 pm
With these it will be smaller, like a computer is smaller once the transistors were connected together by silicon instead of copper.