pulse width limiter

Even cheap scopes usually do signal averaging these days.

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John Larkin         Highland Technology, Inc 

lunatic fringe electronics

Poor man's spectrum analyzer; Normal trigger at the top (~5%) of your noise waveform. Average for max number, adjust time base, press FFT function.

(Does anyone beside me do this?)

George H.

Sure. Been doing it for forty years, with a few more twists, even.

Scope FFTs in 1977? Do tell.

Cheers

Phil Hobbs

Tektronix Signal Processing System. The Tek SPS system I was using in '77 (bought a couple more in another position in the early '80s) had a

7704A/DPO, a couple of R7912 transient digitizers (amazing beasts), and a PDP-11/35 to do the number crunching.

You youngsters might not believe me, but HP and Tek used to charge

*extra* for things like signal averaging and FFT. Really!

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John Larkin         Highland Technology, Inc 

lunatic fringe electronics

Yeah, about a quarter megabuck. ;-)

Or $500 for a little plug-in eprom stick that enabled FFTs. When other people started including that for free, they had to go along.

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John Larkin         Highland Technology, Inc 

lunatic fringe electronics

I don't recall "little plug-in eprom sticks" in 1977. Did we even have PC's?

n

Yah. Not exactly a scope FFT.

I used VAXen in the mid '80s at grad school.

Cheers

Phil Hobbs

Sure it was. Just took a lot more real estate. ;-)

It did have a programming language (Tek BASIC) but FFT (and RFFT, INT, DIFF) were waveform primitives, pretty much like buttons on a scope.

We had Vaxen, too, but they were pretty much just hosted text editing and acted as file servers for other test equipment.

Not in '77. ;-)

I didn't say that the scope FFT plugins happened in '77.

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John Larkin         Highland Technology, Inc 

lunatic fringe electronics

The first EPROM, Intel's 1702 got US patent 3660819 in 1972.

The first IBM PC (5150) came in 1981, using the brand-new Intel 8088 CPU.

Before the IBM PC, there were some computers for personal use, like Commodore PET in 1977, but they were of little use in professional use. The professional computin used mini-computers, such as DIgital PDP-8 and PDP-11, DG Nova and Eclipse, HP

21 series (2116, 21MX ...)

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-TV

The first machine I recall that had a socket for accessory plug-in ROM was the Tandy 100 (1983). That was how you could install a program without using a tape drive.