Saturn-5 LVDC Module Clock

Description

Some time ago, I was very lucky to get an original module from the Saturn 5 rocket - which was used in the Apollo program to take the first humans to the moon.
Other modules have been taken apart by FranLab and EEVblog, but they have already been in a bad condition, so it was not blasphemy to take them apart :-)
I learned a lot from their videos, but (un)fortunately my module is in a perfect condition, so I will not crack it open. But I also don´t want it to be just sitting on the shelf, so I started to reverse engineer it non-destructively by just measuring from the outside.
I could not find a matching connector, but the pins are flat and the row pitch is 1.5mm, same as a standard PCB, so I made an interface out of a PCB.

I already made some progress and will start posting updates soon.

The plan is to make a digital 7-segment watch which reuses a bit of the module´s internal logic - before the date of the 50th Apollo 11 anniversary.

Project Logs

Collapse

Casing and finished product
Paul Kocyla • 02/21/2019 at 16:07 • 3 comments

Here is the finalized product. Better than just standing in the shelf.
And it feels good to know that the module is powered up and playing a role in the clock.
Board working
Paul Kocyla • 02/16/2019 at 13:13 • 1 comment

The Saturn-V LVDC clock is working.
I ordered an acrylic window which will fit over the display. The one I have is too small. It will make the numbers look better.
I´ll put the clock into a wooden case so it can be hung on the wall.
Clock Board
Paul Kocyla • 02/07/2019 at 12:01 • 0 comments

Here´s the PCB layout of the clock with the interface to the LVDC module:
The parts are mounted behind the 1-inch 7-segment displays.
The circuit is based on the schematic by danyk666, it´s a classical counter circuit which uses counters 4060 and 4026. It doesn´t need BCD to 7-segment decoders, as the ICs do the job already. A quick design here, not the most beautiful routing, but will do the job.
Anyway, it´s a quick build.
Reverse Engineering
Paul Kocyla • 02/07/2019 at 11:52 • 0 comments

With a multimeter and and some time I was able to find the following structure:

It looks like a gigantic Diode-AND gate. The diodes have a common anode. I couldn´t find any isolated diodes or transistors.

What else could it be? Maybe a clock distribution circuit where the clock is decoupled by diodes? Or was it used for driving core memory? I don´t know.

However, I will stop the reverse engineering here, as it´s already enough in the circuit to be used in the clock. I will use the AND structure to flip the clock from 59 to 00.