Close

IBM Federal Systems Division Oscillator/Audio Module

A project log for Avionics + mil-spec teardowns

Reverse-engineering (mostly-)cheap eBay finds

don-straneyDon Straney 11/01/2025 at 17:140 Comments

Here's an interesting module that generates an (audio?) waveform from a ROM, at a programmable frequency, using some fun symmetry tricks to reduce the memory needed: https://www.eevblog.com/forum/projects/reverse-engineering-two-70s-military-digital-logic-boards/

Discussions