Say you had just 3 layers: front, middle, back. Vertical tracks on front, horizontal on back. So any crossing point can be uniquely "addressed". On the middle layer you have a solid "groundplane" sort of thing with *optional gaps* at the crossing points.
The addressed vertical "force" track has a high amplitude high frequency signal on it. The horizontal track is a "sense" track going to an amplifier.
If there is a gap in the groundplane at the crossing point, there will be "crosstalk" - a signal current will flow through the capacitance between the force track and the sense track. If the groundplane is solid there then there will be no signal.
Yes! That is one way to do it.
John Devereux
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dagmargoodboat
The Google spam is pretty minimal these days.
not
ple
What's amazing is that, despite a generation of schools failing to teach kids about America, and despite being constantly inundated with misinformation and misled by such people as the press and the President, that the people still have such good instincts, still want to be free.
That's not to say that enough propaganda isn't harmful. It is. But, spending time with liberal neighbors, they too sense something's not right, they too want it better. They're groping in the dark, not seeing. It only needs explaining.
-- Cheers, James Arthur
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dagmargoodboat
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l
The ROM is described on pg. 12 as the a 16-layer PCB. When driven, data and reference lines couple inductively into orthogonally arranged sense lines, constructively or destructively, producing '1' or '0' on the sense lines.
Ingenious.
-- Cheers, James Arthur
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Tom Del Rosso
No pics of the boards?
You could ask some students if they'd like to reverse engineer sections of it. Make it a hiring test.
It's an incredible machine. How many transistors?
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krw
Until you turn them on.
Capacitors work.
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Tom Del Rosso
After the warm up time. :)
Then, once it gets going, the old tube set locks on to every frequency so fast you can spin the channel selector faster than you're supposed to, and you can briefly see every channel as you pass them. When I first got a digital tuner I hated waiting for it to lock on.
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John Devereux
Yes it is clever. I was thinking capacitance, but works in similar way.
John Devereux
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Jan Panteltje
On a sunny day (Thu, 26 Jan 2012 07:07:32 -0800 (PST)) it happened snipped-for-privacy@yahoo.com wrote in :
In a way that money is very relative, look how fast the printing presses roll. That *should* cause inflation, or at least lower the value of the dollar versus all other currencies, but massive demon-rattic speculation against other currencies with as tool gov controlled rating agencies keep the dollar BUBBLE full. Who is gone pinch the bubble? It is all hot air in there so to speak. George Soros, in his book, is describing the 'boom bust' scenario to make money, when will he go short on the US dollar? He also describes the relationship between politics and currencies. So from his POV I'd think that if a republican is elected as president he will go short... and the dollar will then fall to an all time low. Count the days,
We fought Spain for 80 years (the eighty years war), and kicked them out, Imagine you get born in a war and all your life there is war
But this is not about that, it is about seeing the relativity of things, There are plenty in YOUR republican party who employ 'illegal' immigrants, on the farms in the south it is normal. These people work for low wages and often do work that the legal Americans do not want to do, you buy their products maybe even without knowing, Reagan. IIRC, did a general pardon, the idea being that once legal these people will pay taxes, and he needed the cash,,, Europe, my country is flooded every day with immigrants who then apply for visa, those procedures can last years, and in the meantime are supported.
No way, I got kicked out once when I over stayed, IIRC I got 14 days to leave and a stamp in my passport. Later I came back in, they issued a new visa after I promised to be a good guy :-)
mmm I thought you was a republican? Or has that fallen apart in tea and coffee parts?
I dunno, oil companies want profit for their share holders, Saudis, maybe Chinese, may be some Americans, for them if America exists or not is irrelevant, money is power, they may just relocate the headquarters somewhere else, do they care about killed Iraqis? etc etc, just grab the resources, an other reason why the US falls apart, same as happened in Iraq will happen to you.
Right, here I agree.
Sure, what do you do in an earthquake? Run outside, and live. Picture taking for history. I am insured.
I was in Vegas once, and threw in a metal disk, set of all sorts of alarms. (confession).
Old steam generator perhaps, burn some wood. :-)
J
Jan Panteltje
On a sunny day (Fri, 27 Jan 2012 01:14:07 -0500) it happened "Tom Del Rosso" wrote in :
My 46 inch Samsung LCD has 30 seconds 'warm up time', perhaps boots windows...
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Jan Panteltje
On a sunny day (Thu, 26 Jan 2012 08:17:58 -0800) it happened John Larkin wrote in :
Did not some body build a mechanical Turing machine?
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Jan Panteltje
On a sunny day (Thu, 26 Jan 2012 07:14:28 -0800) it happened John Larkin wrote in :
There is not much inflation NOW. But there should be.
Or you will just become Chinese province :-) And the US former president will be unwelcome in China as the Dala lama or whatever his name is.
J
John Larkin
It has, I think, 40 flipflops, in little glopped SIP packages. Plus some drivers and sense amps, deflection stuff, power supplies, like that. Rough guess 150 maybe?
John
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dagmargoodboat
of
The HP Journal article brags about burning in the individual transistors. They also say the circuits are designed for 3MHz, but are only clocked at 1.2MHz. Time for overclocking, eh? HP-9100, Extreme Edition (FPGA, 1GHz).
James
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Tom Del Rosso
An integrated solution would need more than 150 transistors for the keyboard or display.
A JK only needs 2 or 3? I thought more.
Now I'm even more eager to see close-ups of the boards.
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John Larkin
It was common to do a JK with two transistors and maybe some steering diodes.
John
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hamilton
formatting link
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Michael A. Terrell
I used to connect the 'Video output' on my old Polarad spectrum analyzer to a video monitor, and set the end points to cover all the TV channels, and scan them about one per second. It confused the crap out of the local know it alls. ;-)
You can't have a sense of humor, if you have no sense.
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krw
"Locks onto every frequency"? Where are you getting these analog signals for your POS antique?
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Jan Panteltje
On a sunny day (Sat, 28 Jan 2012 11:35:29 -0500) it happened " snipped-for-privacy@att.bizzzzzzzzzzzz" wrote in :
Old VCR with TV analog out will do.
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Tom Del Rosso
Past tense intended.
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