Reverse-Engineered! - Elka S2555-6 and Elka S2556-6
Mar 8, 2025
What is it
The Elka S2555-6 and S2556-6 are frequency dividers.
Those dividers were used in the Elka Capriccio 33/OL to generate the square wave for all the notes of the instrument.
First, the clock from the master oscillator is divided into the different frequencies for the highest notes of each octave by the S2555 and S2556 dividers made by A.M.I. (American Microsystems Inc.) After that, the notes are further divided into all the activities by 12 pieces of AY-6721-6 made by G.I.E.
Why do I have it and where did I get it from
This PCB is one of many analog synthesizers and organ parts I acquired at an auction about 15 years ago.
PCB
Schematic
