interviews

The flip-plane feature?

It's not always trivial on an analog computer. There is only so much dynamic range to piss away.

There are all sorts of them on Android.

Yes, I'm quite sure the early TI calculators were PMOS.

My HP-35 has a chip labelled AMI so I guess not just Mostek fab. I always assumed p-mos technology was used, n-mos was more prominent from mid-late 1970s. There's a bjt blocking oscillator producing bias rails. Power consumption is 500 mega watts (if label is to be believed):)

piglet

I had that problem once, when verifying the math libraries of Fortran on a special-purpose computer. The programmers claimed that the floating-point hardware was broken.

My solution was to do the multiplication problem out manually, on a large piece of gridded paper, in hex, using the long multiplication algorithm we all learned in grade school. The only concession to modernity was to use a hex calculator (TI something) as a base hex

Turns out that it was the programmers that were broken.

Joe Gwinn

A few years ago I was designing FPGAs with 2-D filters for a military project, requiring a lot of binary arithmetic. I found out just how rare calculators are that will do something as simple as fractional binary arithmetic, were. I found only one app for Palm that would do it, and it wasn't RPN. :-(

To no one's surprise, other than perhaps the guilty programmers.

IBM started out with NMOS and were somewhat surprised when they found that everyone else went down the PMOS path. There was a big study to determine whether they had made a big mistake. No, the conclusion was that everyone else had. ;-)

"500MW"?

The HP35 may be pmos, which was common then. It wasn't cmos.

Everything was resistor load or depletion load, essentially RTL. Not very reliable.

The 6800 uP, just a couple of years later, was nmos, resistor load and maybe later depletion load. They worked pretty well.

They were right!

Not sure why you say MOS isn't reliable. It worked well enough.

PMOS was cheaper but, of course, NMOS was significantly faster.

You should not question the self-pronounced expert on Silicon, MOS or substrate diodes... he will shout you down ;-)

All a matter of starting material. The venerable MC1524 Audio Power Amplifier was actually three chips, two with P-type starting material, one with N-type. ...Jim Thompson

The only calculator I ever found that would do fractional math in hex was the original hex calculator from TI.

My first job out of college was at the FCC in Washington, DC. I read in Computerworld an ad from TI for their new hex calculator, for $300 or so (in 1972 or so). I hand-walked a Purchase Order through the gauntlet that day, trying to buy it sight unseen.

Turns out that TI didn't yet make it, and were testing the waters, and had been deluged with preemptive POs. A year later, I had my calculator. It worked very well.

In my prior career as a programmer, in exactly one case it really was the hardware.

Joe Gwinn

We accept that blindly, yet no two have ever been measured the same.

Cheers

By that reasoning, you should also query the interviewee about design of electron microscopes and beta decay.

"Many"??? A few I think. Even buying a tube is an exercise in difficult procurement.

Basics is fine.. for current electronics, but why require them to know about largely obsolete electronics of a day gone by?

Yes, everyone knows baseball is the national pastime here... NOT!

Now you are getting into areas where you know even less...

Yes, no one else in the world ever trades off lives vs. profit... unless it is babies (I guess they don't count as people, no?) and formula profit in China. Where are you from again? No commercial negligence there?

Now you are just off on a rant...

A radio to pick up the none existent signals from all the transmitters using absolutely no semiconductors... right?

Wow. I've seen you post some real nonsense over the years, but this is a new standard. I guess we all need to prepare for Armageddon. Plenty in this country agree with you and are stockpiling food, water and ammo. Is that where your rant is heading... or will you be content to starve while fiddling with your home brew radio?

I don't even know what that means??? Exactly what property do you use to distinguish electrons?

It's kind of difficult to see how they could have intrinsic differences, without some kind of internal sub-structure to allow them to have individual differences.

If you accept the idea of fundamental particles, you are stuck with having them being completely identical, give or take the spin orientation.

Yeah, hardly blindly. You've got the exchange interaction for one.

George H.

It's not intended entirely seriously, but no two measurements of mass, charge, whatever, give the same result, yet we accept that all electrons are the same and the variations must be experimental error.

While the assumption is certainly very useful, it is surely at least possible that it is incorrect. Most things in this field have been incorrect so far, in that new science replaces or modifies old science.

Cheers

The hard part, is why when lots of them are in a pack, they can think.

Kevin Aylward B.Sc.