DIY alternative to Quazar ZXTT module for Ed Brindley’s YM2149 Sound Card (rev. 5)

[Massimo]

Since I couldn't find a 35.469MHz quartz/oscillator to replicate the Quazar ZXTT module (even if it was in stock I would never buy a purple PCB) I built my own alternate version using a 74LS90 in the bi-quinary configuration to divide by then a 17.7344MHz oscillator.

This still provides the 1.77344MHz clock to the sound chip to match the ZX Spectrum.

I got the schematic from here: https://incbtech.com/circuit-bench/829-frequency-divide-by-10-ttl-circuit-using-the-7490-cb253e.html

Here's my module (16MHz for testing, the proper oscillator hasn't arrived yet):