[time-nuts] Fixing broken HP5065A LED clock

Poul-Henning Kamp phk at phk.freebsd.dk
Wed Jan 13 08:38:08 UTC 2016

In message <CAD2JfAjn8OnYpmA0S7rsFo0c4Cw7TgkHxVRoGsGTcUquKijFAQ at mail.gmail.com>, paul swed writes:

>Poul-Henning is that just the back board of the clock?
>I guess I did not realize there were actually 2 boards.

There are 3 and 2 board versions of the LED clock.  Mine is the 2-board

See the section about MM5313 here:


I think you can use my PCB to make the 3-board a 2-board
but you'd have to change some constants in the firmware to send out
50Hz rather than 1Hz.

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

More information about the Time-nuts_lists.febo.com mailing list