Share your knowledge on these two classic MPCs
By mg73 Tue Nov 19, 2019 9:21 pm
Bought an MPC with a broken encoder according the previous owner
bought a new one same problem then got an replacement from the seller, same problem.

So I suspect that the MPC is not register the encoder correct
I tried with a encoder with less detents and that worked
so I reckon that MPC is sensitive to how narrow the pulse width is from the encoder,
not sure i'm definitely not an switch encoder-pro.

Any idea where to start to look?
the 5v is good, and both legs on the encoder have it thru the 4k7 resistors
User avatar
By JUKE 179r Wed Nov 20, 2019 2:08 pm
Where did you get the encoder from? got a website?
try cleaning the encoder internally with Deoxit (not WD40!)?
User avatar
By JUKE 179r Wed Nov 20, 2019 10:59 pm
Jazzcat knows his sh!t so I’d trust him.
By mg73 Fri Nov 29, 2019 8:45 am
It was the encoder,both I got sent!

Borrowed a friends MPC3000 and they didn't work there either.
But the encoder from my friends MPC worked in mine also.

So lesson learned.
Now I just have to found a working encoder...
By mg73 Mon Dec 02, 2019 6:45 am
vout wrote:You probably bought the wrong encoders, there are different types.


According to the seller Jazzcat it was supposed to be MPC3000 Encoders
and it surely looked the same as the original.
By mg73 Mon Dec 02, 2019 6:46 am
mr_debauch wrote:if your friend has a working original encoder, can't you check the model number out and find the values for the part?


The model number isn't a secret but they are not made anymore.
User avatar
By JUKE 179r Tue Dec 03, 2019 11:09 am
The old rotary encoder part number from the MPC3000 service manual is ES-414627J "SW.ROTARY EC24850D0" and yes they aren't made anymore.
Did you try taking your encoder apart and internally clean it? It could be worth a try.
User avatar
By JUKE 179r Tue Dec 03, 2019 1:47 pm
Exactly! Sellers are tight lipped about their MPC3000 suitable substitute encoders. I'm sure Mouser sells one for dirt cheap and not for $70.
By mg73 Tue Dec 03, 2019 7:06 pm
JUKE 179r wrote:The old rotary encoder part number from the MPC3000 service manual is ES-414627J "SW.ROTARY EC24850D0" and yes they aren't made anymore.
Did you try taking your encoder apart and internally clean it? It could be worth a try.


Yes , no luck.
By richie Tue Dec 03, 2019 10:26 pm
JUKE 179r wrote:Exactly! Sellers are tight lipped about their MPC3000 suitable substitute encoders. I'm sure Mouser sells one for dirt cheap and not for $70.


Mouser does not have the part. ALPS made it in very limited numbers back in the 80's and were mainly used by some TV sets.

After a lot of research and reaching out to ALPS direct and other parts suppliers in Asia, I managed to find someone that had a few but wanted $80 each. I found a variant from ALPS that had the same amount of indents however there would be no simple way to wire it in to the control board.

It would be easier to have the control board remade, similar to the 1000/2500 pcb board with conversion in mind for the new encoder than it would be to source the original encoder for the 3000.