Ed the 5065a manual does have the schematics. Its available online free. I think Diddiers site has it. There seemed to be at least 2 chips that were used. Bottom line is the data on how hp used and drove is available which is great news Paul WB8TSL
On Tue, Sep 27, 2011 at 1:54 PM, ed breya <[email protected]> wrote: > I am restarting an old project to transplant my HP Z3801A guts into a 5065A > carcass, and now designing the power system. I'd like to keep the original > LED clock function, but with all new power and interface. I traced out the > circuit partially a few years ago, and am going by the notes I made back > then. > > The clock IC is a 28 pin DIP, marked with the National Semiconductor logo, > and only the code "025B." I assume it is a standard clock IC of the era, > probably PMOS. Does anyone know the true part number? I have never seen a > 5065A schematic or parts list. The HP part number may help if it can be > cross-referenced. I have looked at data on a number of National and other > clock ICs from back then, and saw none that seem to match what's in there. > > Ed > > > ______________________________**_________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/** > mailman/listinfo/time-nuts<https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts> > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
