Sent: Tuesday, August 9, 2016 5:50 PM
So,
patience never being my strong suit, and because really, I should be working, I
have done more work on my ‘retirement project’ with no actual retirement in
sight.
So I
decided to buy some chips from China, because I couldn’t find them here. I can
get most 74XX series stuff, but one part was proving difficult.
A
74LS182. It is the fast look ahead carry generator which helps speed up an ADD
in the adder chip (74LS181) I am planning for the heart of my arithmetic unit.
I think most of the rest of my machine will be 74HCTxx chips for lower power
drain, but it didn’t seem like they ever made these adders in that lower power
technology.
Anyway
I signed up on Alibaba (the Chinese Amazon) and bought these things in Shenzhen, China. So then I said, shit I better get some test equipment so I can
find out if they are selling me rocks or actual working chips.
Completely
amazing how cheap this stuff is, now that it’s prehistoric. I used to have
about $50k worth of test equipment on my bench at Fermi Lab. I think I can get
just about everything for about $500. I saw on eBay an HP freq. counter that I
had to write a ‘sole source justification’ for. It was $5k when I bought it
back then. I saw one on eBay for $150.00. And newer better ones for less than
that.
PS
There
is more to a KI than one might have remembered.
PPS
I have
this nice JPEG of the front panel which nicely fits on my touchscreen monitor.
This may turn into a touch screen version of the front panel, instead of
building one.
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