Original Alps momentary switch for Roland TR-808 Start/Stop or Tap functions. I have a Limited number of these switches available - removed from a spare MC-4 key panel. Alps part number KEH10903 - these switches were used in the MC-4B MicroComposer and I've seen them in later versions of the TR-808. Originally 808s used part number KED10903 which is functionally identical, the difference being that the earlier switches have white stems and are sealed which makes cleaning & repairing them quite tricky. This later style switch is a big improvement and can be taken apart for cleaning should it become necessary in the future. These switches are a drop-in replacement, no problem with fitting the original key caps and they sit at the correct height.
They have seen little use and are in excellent working condition- all have been cleaned and tested in a working TR-808. It’s almost impossible to find these switches “new” today, so if keeping your gear as original as possible is important to you they may be of interest - but be quick, I don’t know if I will have any more once these are gone. *LAST FEW*
Alternatively, if you’re not concerned with total originality, I have replacement switch assemblies available here. These use new Futaba key switches and are a less expensive option.
Only attempt switch replacement if you are confident you have the skills to do so. If in doubt ask a synth tech to do it for you - it’s all too easy to damage the circuit board if you’re inexperienced with soldering/desoldering.
Note: These switches are also compatible with the MC-4 MicroComposer, Boss DR-55 & similar rhythm machines and possibly other Roland equipment of the same period that uses this type of momentary switch. Check your service manual for part number.
*IMPORTANT* If you are ordering from outside the U.K please select “International Shipping” during the PayPal checkout.
Tech Tip: If you would like to repair your own switches take a look at Robin Whittle's excellent TR-808 info page where he details the various types of switch used in the 808. The original white stem Alps switches are fairly tricky to repair - they are sealed and have to be dealt with carefully. These switches lose their conductivity through use, time, build up of oxidization etc and will stop responding, usually when their resistance exceeds 10k ohms. Carefully cleaning the contacts is usually enough to reduce the resistance significantly - often down to tens of ohms - obviously the lower the better but anything less than 1k ohms is fine and should be achievable by cleaning. For longevity it's obviously better to replace the switches, either with the later Alps switches (as shown above) or with new replacements such as the Futaba key switches that I have available Here.