This section is *not* finished yet.

The logic for the TTLDrum is fairly straightforward, internally it uses 5v TTL levels to communicate and the PSU is any switcher really that can supply ~1A.

Stability has been a problem previously, but after sprinkling the board with 100nF caps at every VCC this problem (seems to) have vanished.

The voiceboard is a DR110 clone which is not even near perfect. No real effort has been made to resemble the DR110 and the sounds are currently quite weak. This doesn't outdo the idea of the TTLDrum since the goal was only to build the sequencer. Also, internally the trigger outputs are separated so that the lower voiceboard can be tossed and a new one inserted.

There's no denying that this project was kind of stupid from the beginning, i would definitley not recommend anyone to try and build this unit due to the many inconsistencies and design flaws. The schematics are only to be used as a inspiration to other, better, projects.

Some day, in the future, i will try and put up ALL schematics, but for now, this is it: