They were whisker types - not PN junctions. Ge had most - as it was high frequency and Si wasn't.
Yes there were PN diodes but mostly whisker - in the late 50's. Limited use and not for high rel at all.
C> >
Si-diodes in Second World War radar & Communication equipment
Apr 12, 2008
164 Replies
Every one forgets the Cold war. B-36's and B-52's and such were all vacuum tubes. EMP and radiation didn't wipe them out as semiconductor was. Transistors were in the 40's post war at Bell Labs. Nobel time.
I looked over my MIL books and didn't find a semi in power supplies or in radios or detectors...
I think MIT and Bell Labs were experimenting with the new stuff as a sight into the future.
Diodes - point and semi were in use but radios were miniature vacuum tubes and turned transistor in 57.
TV sets used selenium rectifiers stacks for years before Semiconductor were able to make ends meet. I think the big break for them - the electronic terminal and smart printer in the 70's and 80's.
Mart> >
The EMP became an issue in the 1960's after the nuclear test above the Pacific, so it could not have influenced the much earlier B36/47/52 designs.
Apparently the semiconductor diode reliability was not very good since some early computers had a lot of problems with semiconductor diode reliability. For instance ENIAC had nearly 18000 tubes but only 7000 semiconductor diodes. If I had to design a computer with tubes and diodes today, the amount of diodes would be at least ten times the amount of tubes.
For microwave receiver applications, if you do not have a good low noise RF amplifier, a point contact diode mixer is a reasonable alternative (often driven by a LO frequency multiplying chain) to get a reasonable system noise figure/temperature.
Paul
That\'s kind of ambiguous, but since I\'ve proved you wrong before, I
guess you\'re talking about the killing thing, in which case why should I
worry???
BTW, how tall are you?
JF
Not tall, not short... close to 1.0 SPunits, or roughly 0.9 PHs. Just about right for the business I'm in and the women I like.
But, given the choice, I'd rather be a bantam rooster than two big old hens.
Done any interesting electronics lately?
John
Hmm...
"Which is why you remind me so much of Miss Denton, my matronly 6th
grade teacher."
"I\'d rather be a bantam rooster than two big old hens."
Interesting how you try to belittle your opponents by feminizing them,
and it sure speaks volumes about how you think of women...
Anyway, 6\' 160 pounds is hardly a "big old hen".
I love women, in all sorts of ways. All my best friends and all of my business partners have been women. All of my wives, daughters, and sisters, come to think of it.
But if critters peck like hens and cluck like hens, they're probably hens.
Stewer.
John
I know for a fact the B36 and 52 were tube models.
Later when the 52 got cruse missiles - anything goes. It had to. I trained the designers of the F-111 and prior to it, they made B52's. I took them from R/C/Tubes to Solid state and digital. Op amp as well.
Bikini wasn't the first bomb and Electronics was in tubes then. Computers were tube as well.
Mart> >
So say tou, and yet you try to use the image of them as being inferior
to further your own ends?
You're babbling again. I made no negative comments about women, and I have no ends other than to share knowledge and amuse myself.
I do think that barnyard roosters and hens are both silly animals, but that you and JT act more like hens.
Now who is debasing women?
No, I just had breakfast with my beautiful, smart, skinny wife. Now I'm thinking about electronics [1]. You should try it some time, and take your mind off gossiping and clucking and various fantasies about other peoples' personal lives.
John
[1] I'm trying to design a 16-bit, 500 KHz ADC with a really good PGA front-end, 15 volts of 120 dB CMRR, ranges from 20 mV to 12 volts, low noise and drift. Nobody makes 16-bit SAR ADCs with PGAs, and no commercial PGAs can do what I need. So it will have to be made from parts... not too many parts, since I need 16 channels on a VME board.Or maybe I'll just pick blackberries and make a batch of bread pudding.
Until Starfish Prime July 62 EMP was not appreciated as being as destructive as it is. It was at 248 miles up. Ground burst and other atmospheric detonations do not create EMP.
Eric
Paul -
I know what was on the B-36 and B-52 - Radar and radio.
Tube tube and tube. I trained the F-111 designers for the first solid state plane. It had a lot of firsts - swing wing... Fast and slow.
I used to have tens of thousands of tubes. Mil spec. They would use them for 100 hours and replace them.
Bikini - used to live hundreds of miles from it - wasn't the first at all - nor was those in Japan.
The bomb was tested in the states long before anywhere else. Knowledge was gained on a number of fronts.
Mart> >
But theory and Science knows more than you. Much more was known long before as the bomb was known before they figured how to make one.
Mart> Mart>> I know for a fact the B36 and 52 were tube models.
What?
About 5'6". I met John at one of those trade shows in LA, and got about a half-dozen of his refrigerator magnet logo thingies. Apparently I voided the warranty when I stuck them to my file cabinet. ;-)
He's adorable, like a friendly leprechaun. :-)
His face wouldn't frighten children the way yours and mine do. ;-D
Hope This Helps! Rich
PKB, methinks.
What you should try sometime is growing up and owning up to a mistake
like a man instead of always starting a childish row to divert attention
away from the fact that you made a mistake.
JF
Yeah, it does.
Thanks! :-)
JF
Around Christmas time, in the grocery store, little kids point at me and say, "Ho! Ho! Ho!" ;-)
And I've never seen a kid yet that I couldn't get to smile.
...Jim Thompson
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Which mistake are you referring to?
Do you keep a scrapbook of my mistakes? I'm flattered.
John
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