Welcome to
The next page of stuff.
I can only apologise for the main page fiasco. I had no idea that I would generate so much so called content
IBMs' network over CATV cable card interface for IBM PCs
What is this ?
This
is IBMs' network card from the early eighties for the original
IBM PC. I cannot imagine how much this card would have originally
cost. Judging by the cards complexity it would have cost more than the
PC. This card predates generic coaxial ethernet (IEEE CheaperNet) by a
number of years. The analog electronics on this card is a radio
modem that uses CATV cabling. IBM then saw that there allready existed
a large amount of CATV cabling in buildings. The cards radio could be
tuned to unoccupied chanels to establish a radio link. The radio modem
is made from high quality components and I suspect was capable of full
duplex operation at probably one or two megabits/second. The IC
under the heatsink at the left is a first generation Intel ethernet
controller chip. The square chip is an 80286 cpu. The network
controller had ten times the mippage of the PC into which it was
plugged. IBM thought CATV cabling was the way to go because the
technology was allready ubitquitous and there was a large pool of
technicians that could install and terminate CATV cabling and
accesories.
I found a large carton of these devices in a
dumpster and it was a lucky find indeed. There are many UHF large
signal bipolar transistors on this card adn they were very welcome for
my ham radio activities. I dont know what this card was called or what the original cost was.
The
AIRMEC type 871, ZD 00783 OSCILLATOR TEST No1 CT212
A very nice signal generator picked up at a hamfest for $10. Works, but
not very well, its a bit ill. I
would really appreciate a circuit
or manual.
Beautifully made, Larkspur like construction practices and very high
biuld quality. The paint color suggests it was made for Naval
use.
Internally a bit too compact to allow easy reverse engineering.
Internal components are very similar to things found inside a C42
The
Burroughs B7800 and my part in its maintenance.
Including
burroughs chip house codes to commercial equivalents
Larkspur Control Harness Project
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| controls for C13,C42 and C11 | my poor excuse of Larkspur quality! | C13,C42 and C11 |
inspired by the Black Dog
