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Vintage Synth Repair

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roland U20

roland U20

2011-08-08 by colinbutterfield@ymail.com

Hi, I have an old Roland U20 keyboard,when powered up,only the bottom and the top keys on the keyboard work,all in between do not produce a note.Everything else seems fine,any ideas?? Cheers Colin

Re: [vintagesynthrepair] roland U20

2011-08-08 by Noel Buhagiar

Hi Colin,
You could try and connect it to another synth using MIDI IN-OUT and see if it plays ok.
If it does, problem could be a bad keyboard and then you’ll take it from there.
Old U-20s were known for the sticky-keys problem; are the keys free when played?
Hope that helps & keep us posted
Regards,
Noel

  
Hi, I have an old Roland U20 keyboard,when powered up,only the bottom and the top keys on the keyboard work,all in between do not produce a note.Everything else seems fine,any ideas?? Cheers Colin

Re: [vintagesynthrepair] roland U20

2011-08-09 by colin butterfield

Hi Noel,connected it via midi to my yamaha and the yammy will play the U20 but U20 won't play the Yam,just top & bottom note so seems like the keyboard.All the keys play freely.I can understand all octaves of certain notes not playing as keyboards  are usually addressed as a matrix,but all notes in between has me stumped.Any other ideas gratefully accepted.Colin.
Show quoted textHide quoted text
  ----- Original Message ----- 
  From: Noel Buhagiar 
  To: vintagesynthrepair@yahoogroups.com 
  Sent: Monday, August 08, 2011 10:31 PM
  Subject: Re: [vintagesynthrepair] roland U20


    



  Hi Colin,
  You could try and connect it to another synth using MIDI IN-OUT and see if it plays ok.
  If it does, problem could be a bad keyboard and then you’ll take it from there.
  Old U-20s were known for the sticky-keys problem; are the keys free when played?
  Hope that helps & keep us posted
  Regards,
  Noel

    
  Hi, I have an old Roland U20 keyboard,when powered up,only the bottom and the top keys on the keyboard work,all in between do not produce a note.Everything else seems fine,any ideas?? Cheers Colin

Re: roland U20

2011-08-09 by narfman96

I don't believe the U-20 is powerful enough to to have key assignments that will exclude certain zones of the keyboard. You might try a removing the battery for an hour (there is no ROM reset) or so but I still don't think that will help.

First I would check the key contact rubbers under the keys in the keyboard first. They are subject to years of dust and anything that may get spilled on the keys. They are also known to fail. Look around on the web and see if you can find some pics or maybe even a procedure detailing the ins and outs of removing the keys and fixing the contacts. Any D-10, D-20, D-50 even the newer PCR-30 or 50 should be very similar.

I recently rebuilt an Edirol PCR-30 from parts I ordered from Roland US so there is hope for parts if you need them. If you need more help tell us what you found and we will be glad to glad to help if we can.
 
Good luck,  Fran  (and no not the little mouse in my pocket... the rest of the members here at VSR.) 

--- In vintagesynthrepair@yahoogroups.com, "colin butterfield" <cjbutterfield@...> wrote:
Show quoted textHide quoted text
>
> Hi Noel,connected it via midi to my yamaha and the yammy will play the U20 but U20 won't play the Yam,just top & bottom note so seems like the keyboard.All the keys play freely.I can understand all octaves of certain notes not playing as keyboards  are usually addressed as a matrix,but all notes in between has me stumped.Any other ideas gratefully accepted.Colin.
>   ----- Original Message ----- 
>   From: Noel Buhagiar 
>   To: vintagesynthrepair@yahoogroups.com 
>   Sent: Monday, August 08, 2011 10:31 PM
>   Subject: Re: [vintagesynthrepair] roland U20
> 
> 
>     
> 
> 
> 
>   Hi Colin,
>   You could try and connect it to another synth using MIDI IN-OUT and see if it plays ok.
>   If it does, problem could be a bad keyboard and then you’ll take it from there.
>   Old U-20s were known for the sticky-keys problem; are the keys free when played?
>   Hope that helps & keep us posted
>   Regards,
>   Noel
> 
>     
>   Hi, I have an old Roland U20 keyboard,when powered up,only the bottom and the top keys on the keyboard work,all in between do not produce a note.Everything else seems fine,any ideas?? Cheers Colin
>

Re: [vintagesynthrepair] Re: roland U20

2011-08-09 by Daniel Forró

Some instruments could do such strange split when Hi Note was set  
UNDER Lo Note. But this is not U20 case.

First I would try patch initialization as described on page 147 of  
Owner's Manual:

Initialize ALL

Then try to play again.

If it doesn't help, you can try test and memory initialize  
procedures. You will find them in Service Notes downloadable from  
this web page:

http://digilander.libero.it/solurghhomestudioext/manuals.htm

And if this doesn't help. you can try to open the instrument, check  
if all cables are properly connected, eventually to reseat all IC's  
in sockets, disconnect and again connect all connectors. Be careful  
not to destroy anything. If you haven't enough experience with such  
repairs leave it to specialist.

If this doesn't help then there's bigger problem which should be  
repaired by specialist. Maybe some IC is dead...

Daniel Forro
Show quoted textHide quoted text
On Aug 9, 2011, at 9:30 PM, narfman96 wrote:

> I don't believe the U-20 is powerful enough to to have key  
> assignments that will exclude certain zones of the keyboard. You  
> might try a removing the battery for an hour (there is no ROM  
> reset) or so but I still don't think that will help.
>
> First I would check the key contact rubbers under the keys in the  
> keyboard first. They are subject to years of dust and anything that  
> may get spilled on the keys. They are also known to fail. Look  
> around on the web and see if you can find some pics or maybe even a  
> procedure detailing the ins and outs of removing the keys and  
> fixing the contacts. Any D-10, D-20, D-50 even the newer PCR-30 or  
> 50 should be very similar.
>
> I recently rebuilt an Edirol PCR-30 from parts I ordered from  
> Roland US so there is hope for parts if you need them. If you need  
> more help tell us what you found and we will be glad to glad to  
> help if we can.
>
> Good luck,  Fran  (and no not the little mouse in my pocket... the  
> rest of the members here at VSR.)
>
> --- In vintagesynthrepair@yahoogroups.com, "colin butterfield"  
> <cjbutterfield@...> wrote:
>>
>> Hi Noel,connected it via midi to my yamaha and the yammy will play  
>> the U20 but U20 won't play the Yam,just top & bottom note so seems  
>> like the keyboard.All the keys play freely.I can understand all  
>> octaves of certain notes not playing as keyboards  are usually  
>> addressed as a matrix,but all notes in between has me stumped.Any  
>> other ideas gratefully accepted.Colin.
>>   ----- Original Message -----
>>   From: Noel Buhagiar
>>   To: vintagesynthrepair@yahoogroups.com
>>   Sent: Monday, August 08, 2011 10:31 PM
>>   Subject: Re: [vintagesynthrepair] roland U20
>>
>>
>>
>>
>>
>>
>>   Hi Colin,
>>   You could try and connect it to another synth using MIDI IN-OUT  
>> and see if it plays ok.
>>   If it does, problem could be a bad keyboard and then you’ll  
>> take it from there.
>>   Old U-20s were known for the sticky-keys problem; are the keys  
>> free when played?
>>   Hope that helps & keep us posted
>>   Regards,
>>   Noel
>>
>>
>>   Hi, I have an old Roland U20 keyboard,when powered up,only the  
>> bottom and the top keys on the keyboard work,all in between do not  
>> produce a note.Everything else seems fine,any ideas?? Cheers Colin
>>
>
>
>
>
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