HP-75C with 82169A Interface |
HP-9825A |
HP-9915A |
For the technically minded ...
This setup was created by linking an HP-9915B to two HP 59306A Relay Actuators. Each 59306A has 6 relays that can switch 28 Vdc or 115 Vac at 0.5 amps. A separate string of decoration lights was connected to each relay. The decoration lights are set up to remain always on, so we can turn them on or off via the appropriate 59306A relay. A total of 12 strings of lights were connected to the two 59306As, one per relay.
A program running on the 9915B turns each relay on, or off randomly. At the same time the 9915B display LEDs are used to display the sequence number (in binary).
The "blinkenlichts" program has been ported (with minor modifications) to a number of other systems including the ones shown below:
|
HP-75C with 82169A Interface |
HP-9825A |
HP-9915A |