[vcf-midatlantic] Hayes 300bps SmartModem for museum exhbit?

Herb Johnson hjohnson at retrotechnology.info
Sun Feb 2 14:23:40 EST 2020

> Was it the Hayes (internal S100) listed below? Seuss himself just 
> mentions a "Hayes 300 baud modem card" at:
> https://www.chinet.com/html/cbbs.html

I know plenty about S-100. I'm pleased to see an opportunity to show in 
the 21st century that S-100 was (again) a trailblazer in personal computing.

The discussion at the linked Web page seems clear to me, that the card 
referenced was a S-100 product. The people in discussion state that 
testing was "very early in Feb" of 1978. One can research to see what 
Hayes products were available on that date. But one Hayes S-100 card I 
saw today says on the card "1977-1978"

The linked discussion is from Randy Suess and - not mentioned here - 
Ward Christensen. Ward developed a number of early - I'd call legendary 
- programs which were distributed later by CPMUG and SIG/M in their 
diskette libraries. Don't forget him.


shows a Hayes 80-103A modem card and discusses some of its history. The 
site also shows a Hayes Micromodem-100 and claims it was "second". 
Another S-100 modem brand was PMMI; the MM-103 is also shown at 
s100computers.com. Note John Monahan mentioned the Hayes card needed a 
PMMI coupler. There were probably other brands of S-100 card modems.

These cards for various reasons, did not include a "coupler", the device 
that physically connected to the telephone. That's for historic reasons; 
look it up.

There were several key technologies needed to produce a modem; and a 
little bit of regulated commerce was involved. They all came together at 
the time to enable such a product to arise. Of course: the 
microprocessor computer with mass storage created a need. Yes, there 
were remote terminals in use and that was a market, but most terminals 
were wired in or used leased lines. There's other considerations I'm not 
putting into this simple post; go research late-1970's computing. I was 
a BSEE and minicomputer system manager at the time, I experienced some 
of this stuff, and so I'm simply commenting from memory.

I find that modern people looking back, think that modems were "natural" 
even obvious. No, they weren't, they occurred at a point in time for 
historic reasons. I've suggested a few. It's entirely up to the 
exhibitors to decide, whether or not to portray that background in their 

Herb Johnson

Herbert R. Johnson, New Jersey in the USA
http://www.retrotechnology.com OR .net
preserve, recover, restore 1970's computing
email: hjohnson AT retrotechnology DOT com
or try later herbjohnson AT retrotechnology DOT info

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