Ethernet 1973/1974

Al Kossow aek at
Wed May 17 11:55:39 CDT 2017

This is an early version. They made some changes like adding a protection diode and resistor on the coax input
after a nearby lightning strike at PARC wiped out a bunch of them. I guess I should pull apart the original Xerox
10 meg one which was designed by the same guy to see how similar they were.

I've been having lots of problems with shorted 10uF rat turd tantalums in the 3 meg ones as I've been bringing up
the net to interconnect the restored Altos at CHM.

On 5/16/17 8:47 PM, Shoppa, Tim via cctalk wrote:
> Al just recently put this up on Bitsavers, November 1974 drawings for the first 2.94MHz Ethernet transceiver:
> Neat to see the 15 pin AUI to Thicknet transceiver (well, a lower bandwidth version of the 10MHz ones I grew up with) drawn out so clearly. Also shows something I've never seen in real life, an "Ethernet Dummy Transceiver" which is, I guess, something like a two-port DELNI ? (obviously showing my DEC introduction to AUI Ethernet there.)
> Tim

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