[time-nuts] HP internal part numbers.

Rex rexa at sonic.net
Sun Jun 18 01:33:34 EDT 2006

On Sat, 17 Jun 2006 22:08:19 -0700, Rex <rexa at sonic.net> wrote:

>I'm trying to figure out the basics of some circuits in my HP Z3816A
>timing receiver.
>There are two chips in it marked with this HP part number:
>They are 14-pin DIP chips and seem to be made by National Semi.
>Does anyone have a reference list or link that might cross-reference the
>HP part number to a standard part number or description?
>From the context of the board, I am guessing they could possibly be PLL
>chips. If no one can look up the numbers, can anyone suggest National
>PLL chips in 14-pin dip that might have been used by HP around 1996? I
>could try some guess work.
>Thanks for any help.

I think I answered my own question. Found a big cross-ref list here:

Looks like 1820-5950 is a 74AC04SC

Much less complicated chip than I had guessed.

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