D17B Control Panel Binary Clock

Sometime in 1999, Tom Jennings gave me a register display from an old Autonetics D17B Minuteman I Missile Guidance Computer (circa 1961).

I have been working on converting it to a binary clock. Perhaps some day I'll explain why. In the meantime, don't worry, I'm not making any physical changes to the unit, so it will be fully capable of being re-married with a D17B system in the future in order to help guide minutemen missiles at whatever.

Progress:

Last night I tested the main relay board, which has been sitting for at least a year and a half. It works. I also discovered that I had already started on the second board, and had finished the relay part of that board. For inspiration I wired up the first four digits of the display (what will become the hour) to see what it'll look like, and took a few pics. As you can see, it was 11 o'clock.

2002-01-01

I have the schematic finished. It uses an 8bit PIC microcontroller. I haven't written the software yet. I've done a few little test circuits, to make sure the components will work together correctly.

I have purchased all of the components (MCU, bulbs, relays, transistors). I removed the old bulbs, and have put in more standard 12V bulbs that have a flattened end, so it focuses the light for this application better than the old bulbs. The display is now much brighter. I had to de-solder 120 connections from the back of the display. That took a while.

To the left is one half of the circuit, and it's been tested. I have to do the second board (the MCU board), which is the same size as the one pictured. When it's finished, they'll both be stacked together. After I finish the second board, I'll have to hook them together, and then hook the dual board to the back of the D17B display (lights) and the time setting switches. I also have to super glue a piece of plastic that broke off the back.

2000-03-19

v0.0.1 of the binary clock code. I tested this on a breadboard with LEDs to simulate the display. It counts; it's not a clock.

Documents:

More Photos:

Related Links:

D17B Computer Information

A lot of information about the D17B Guidance Computer

Jason Harper's Nixie & Dekatron Clocks

Has a small bit about rear projection incandescent displays half way down the page, saying, "Of all the antique display technologies I've played with, this is perhaps the highest quality one" There are also some ideas about converting old displays into clocks.

Counting & Display Tubes

This survey of old display technologies has a brief mention of rear projection displays.

Tom Jennings