A few days ago I bought a Roland D-5 synthesizer that’s in desperate need of some TLC. It looked VERY dirty and most screws from the bottom plate where missing but the guy said it sort of worked and it was cheap so I bought it 🙂
It came out in 1989 and back then it was the cheapest multitimbral synthesizer on the market. It has the sounds of the D-10 and D-20 but no effects or sequencer. Editing sound is done via the menu and some buttons but you can also connect a PG-10 programmer to it to make editing easier.
At home I plugged it in to see what was working and what not. I was surprised to find out that all the keys worked just fine. Especially when I later found out how dirty it was inside and that it has the same keybed construction as the U-20, D-70 and JD-800. Keybeds that are somewhat notorious for, well, not working 🙂
I took the thing apart and this is what it looked like:
The red stuff is melted candle I think..
I also discovered that most of the buttons didn’t work. On the inside it looked like the world supply of WD-40 or something like it was sprayed on the PCB that contains the buttons.. That apparently didn’t work so I’ll be replacing all 38 tact switches in order to fix that.
In the meantime I’ve cleaned the keybed and reassembled it:
It looks and feels brand new 🙂
When reassembling the keybed take note that the C and F keys are identical as are the E and B keys. See the inscription on the keys:
The number behind it is just a mold number. So CF12 is identical to CF13 or CF14. The black keys are all identical.
If you ever take apart a D-5, U-20, D-70, JD-800 of KR-xx model and you see this connector:
DO NOT SEPARATE OR TAKE APART IN ANYWAY! Those parts are glued of heat pressed together. Separating them will destroy the traces and basically ruin the keyboard. I’ve (succesfully) fixed this on a D-70 once and I hope I never have to do it again 🙂
Next thing to fix are the buttons that don’t work. I bought 100 tact switches online and found out that they don’t fit because I need 2 pin switches instead of 4 pin. The 2 pin variant is a lot harder to get. The only place that sells them online seems to be AliExpress.. delivery time 15 to 60 days 😦 I send a couple e-mails to Dutch shops to see if they can deliver the 2 pins but I think I’m going to order them in China tomorrow.
In the meanwhile: I have a lead on a XP-80 and a XP-50 that both produce no sound. I little Googling tells me that XP’s have the tendency to self-destruct after 20 years of service. A lot of these instruments suffer from leaking capacitors and those will need to be replaced. No guarantee that it’ll work because the acid from the leaking capacitors could have wreaked havoc on the mainboard. I’ve never replaced bad capacitors before but I’m always in for a project 🙂 Lets see if I can buy them cheap.
Update feb 4 2015:
I found the tact switches in a Dutch online shop and they’ll arrive tomorrow! I also bought the XP-50 today and I’m going to pick it up saturday. Still negotiating with the XP-80 owner..
Update feb 8 2015:
Today I replaced all the tact switches. Here the old ones:
And all desoldered:
I just grabbed the back of the tact switch with my finger nails and with my other hand used the soldering iron the heat up the solder. I could pull them right off. Very easy. With 4 pen tact switches instead of 2 pin it probably would have been harder.
And the new ones in place:
Afterwards I clipped of the excess pens you see sticking out in the pictures above.
Then I cleaned the last few gallons of WD-40 from the insides of the synth and put the whole thing back together. Powered it up and everything works like new! I’m able to select all patches and all the other buttons work fine too. All 38 of them 🙂 Beer!
I’ll play around with the synth the next couple of weeks and find out if it sounds cool too.