[Coco] Selling my 512k Coco-3 and related items
SFischer1 at Mindspring.com
Fri Dec 7 20:19:10 EST 2018
Well after a nap I realized that the first ICs I got were RTL, Resister
Transistor Logic. I have a book full of them and about 75 Gold plated
ICs in my parts bin.
Then there was the Transistor Transistor Logic, a book for T squared
Logic with ~ 100 - 200 ICs of then of various types and then came MOS,
CMOS, with lots more books and then Linear.
I ordered about 9 books from National and got about four. I drove over
and was directed to the right building where the lady at the desk told
me to go through a door which I did. I was then at ground level
overlooking a huge building that went down about four floors and was
able almost to allow several 747s to take off at the same time next to
each other. I got my books but was totally amazed as it was ALL BOOKS.
What totally amazes me is what I used narrow tape laid down on bare
copper boards to make PCs the experts today are using their computers to
design CoCos on a chip or other circuits, ordering PC boards to add IC's
without legs or even getting fully ready to use boards from China in a
I remember the first IC a Professor was so proud of as he had put in in
a circuit with some switches and lights that demonstrated that it was a
working AND gate. That was the one and only IC at that time in the
entire Electrical Engineering department of the University of Wisconsin.
On 12/7/2018 3:45 PM, Bill Gunshannon wrote:
> On 12/7/18 4:54 PM, Stephen Fischer wrote:
>> Tie Sync together??????
> That's what I thought, too. But the picture states that he has HS and
> VS tied
> together run through a resistor connected to the Sync line of an RGBS
> He has pictures that seem to show it working, but I don't know how.
>> The only way is to use an NOR chip, 74??00 if I remember the number
>> correctly. Then if needed to invert the polarity another NOR gate is
>> available on the IC.
> He has an example of such a combiner but claims he didn't need the
> complexity and just used the cable.
> I admit to being baffled.
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