On Fri, 01 Feb 2013 18:53:59 GMT, the renowned Jan Panteltje
wrote:


In the late sixties or maybe very early seventies I build a frequency counter
with 4790 decade counters, and 7475 latches,

7490.. one of the TTL chips with power pins not in the corners.

cannot remember the number of the nixie driver chips, also TTL.

7441 or 74141

It had a 100 kHz crystal as reference, 5 digits, counted up to about 30 MHz,
as that was the maximum where the TTL would still work.


Best regards,
Spehro Pefhany
--
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