tactile switch

dunno if this is redundant or helpful but i just wanted to post the part numbers for the three different types of tactile switches found in the MPC4000. all are made by ALPS (oem) and are currently available from mouser.

SKQEAD
SKHHAM
SKHHAL

and if you wanna do the work yourself some pertinent info from alps' website:

Manual Soldering

Items Condition
Soldering temperature 350℃ max.
Duration of soldering 3s max.
Capacity of soldering iron 60W max.

and finally: compared to the corresponding omron parts the alps have a much more positive "clicky" feel.

hope this helps.

- jim

Yeah, thanks mate this is good, as mine will need some tact switches in the near future.

These Alps versions appear to be rated to 10 million presses operational life so they should outlast the MPC... and probably me as well!

Sorry to be a pain Jim, but which of those tact switches/ part numbers are for which buttons on the MPC?

off the top of my head (and please correct me if i'm wrong):

SKQEAD - 12.0x12.0x4.3 - used for transport controls and maybe a few more things...i'm not in front of the machine right this second.

SKHHAM - 6.0x6.0x5.0 - this switch is the most prevalent. block cursor, numbers, etc. - most of them are this switch.

SKHHAL - 6.0x6.0x4.3 - used for pad banks and all the controls to the immediate left of the pads. conveniently enough the pcb tells you which ones are this switch.

it's kinda hard to confuse the 12mm with the two 6mm switches. the two 6mm switches are different heights which is pretty apparent once you get them removed. this was my first foray into replacing the switches and i thought i'd share what i learned. it is by no means comprehensive as far as what goes where but a quick look with the top cover removed should clear up any confusion you might have.

Cheers!

Jim, how tricky was it to remove the old switches and solder on the new ones? I'd really like to do this, but I don't have complete faith in my soldering skills so I'm thinking about buying the switches and taking it to a electronics repair specialist.

not tricky at all if you're experienced with a soldering iron. however, if you are unsure i'd recommend taking it somewhere. a little too much heat and you could cook a component or fry a trace and then you're screwed. you could always practice on some pawn shop piece of crap just to get good at soldering printed circuit boards. you'll need a decent (digital) iron and a solder sucker/wick/etc.

- jim

jimfowler wrote:not tricky at all if you're experienced with a soldering iron. however, if you are unsure i'd recommend taking it somewhere. a little too much heat and you could cook a component or fry a trace and then you're screwed. you could always practice on some pawn shop piece of **** just to get good at soldering printed circuit boards. you'll need a decent (digital) iron and a solder sucker/wick/etc.

- jim

Thanks Jim, I think I'll probably take it to an electronics repair specialist. I have a similar issue to you I think, buttons are totally functional but seem very worn and don't really have a great feel. I've tried switching around the less used buttons to more worn (i.e. Record) but it still feels weak so I figure it is the tactile switches that need changing.

I'm trying to weigh up the money it'll cost and how much of an impact it'll really have versus how much better it'll feel when the buttons click more than ache, so to speak. Sounds like you really noticed a difference which is encouraging.