DDM stands for "Digital Drum Machine"- this is Latino ethic version of Korg DDM 110 drum machine (here free samples) , a bit the kind of TR727 and TR707 from Roland. It features a basic sync system (no midi) a sequencer and a bunch of sampled sounds: Hi Conga, Lo Conga, Timbale, Wood Block, Cowbell, Hi Agogo, Lo Agogo, Cabasa, Tambourine (it can be used and external +5V Trigger for some simmons stuff).
Following previous Roland MC303 entry: the DDM220 was bundled with the techno Japanese Groovebox. I already have one of this. Even if not really considered as a Linn DRUMM (the sound is not the best of the world) or a Tr-909, I think this are fun especially for sync function to mix with other modular sequencer. Finllay I read somewhere for a separate output for this model and its brother DDM110. Maybelater (if you have info, please contact me but NO circuit bending :)
Well, it's disgustingly dirt and the push buttons, pads are not working at all, no wonder with all that dusts it took. I tried to power it on, and it seems to work pushing really hard the pads (not really good for the board). Fun enougj, some messy symbol appeared on the screen at beginning that gone after a couple of reset.
So let's open it this incredible poor's man Tr727.
UPPER Really a pleasure to open with only 5 screws on the rear side. The battery slot is quite in order, that's quite surprising.
UPPER - Second step is to remove the 2 screws on the card protector, and remove the ones that retain the switch board. Just two ribbons to remove, quite easy, but don't bend the pins.
UPPER now THAT was gross: a lot of dirt inside , I wonder what happened to this drum in the last 40 years around. But nothing a good soaping water could remove, after many brushing.
Now back to the circuit.
A lot of dirt also around the pots that became sticky probably someone sprayed some deoxit without prior cleaning. That usually creates a kind of gum. Qtips is your friend.
Also a quick inspection does not reveal any oxidation in any part of the board, I appreciate that.
UPPER: Keep your Qtips around and some Isopropyl Alcohol. GENTLY open the buttons, prying the 2 the plastic protections, the upper part should pop up without too many pressure. Disassemble the button but DON'T break nor bend the plastic parts. Clean the 2 golden contact with you qtips, and also to the rubber conductive part. Repeat for all buttons (a loooong job).
Ok just a few screws and you're there. Ok, seems to be working.
If you need it, here's the english user manual and here the SERVICE MANUAL (also for DDM110)
Mobirise web page software - Click here