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problem with JP-8000, pitchbend /lfo 2 section.

problem with JP-8000, pitchbend /lfo 2 section.

2010-10-04 by Bakis Sirros

hi lists,

i recently got a 'battery low' message in my jp8000, so, today, i changed the battery (with the correct type of course). it was an easy process and was careful not to touch other electronics inside the machine. i also used midi-ox to dump all the sounds and after replacing the battery i reloaded all info in the machine with no problem.
but, now, the pitchbend does not work (it works, but has a very limited range of less than a semitone) plus the 'lfo 2' section does not work (the 'lfo 2' does not affect pitch or filter or amp), and the ribbon controller affects parameters but is only sensitive to tough (like an on-off switch) but not position as it also was...

i suspect something from the controller section left of the keyboard is damaged or disconnected... (i did the mistake and put the upside-down jp800 in a hard surcface when i was changing the battery...)

any further ideas / help please?

many thanks in advance,

best regards,   :-)
Bakis.


Bakis Sirros - Parallel Worlds / Interconnected / Memory Geist
[Doepfer_a100] group owner
www. parallel - worlds - music. com
www. myspace. com/ parallelworldsmusic
www. myspace. com/ interconnectedmusic
www. myspace. com/ memorygeist
www. DiN. org. uk
www. musicamaximamagnetica. com
www. vu-us. com

Re: [vintagesynthrepair] problem with JP-8000, pitchbend /lfo 2 section.

2010-10-04 by Daniel Forró

Kali mera,

it looks really like problem with some connector, or short circuit on  
some cable (maybe cabel is pressed somewhere). So I would check once  
more everything inside.

If it is not hardware problem, it can be software problem, but  
objectively there's no reason for such behavior if you didn't make  
some fatal mistake during changing the battery.  One never knows,  
maybe there are CMOS chips, and statics is dangerous...

Anyway, 30 seconds of googling revealed to me how to enter  
diagnostics mode, you can try calibration routine for pitch bend and  
mod:

******************
1. Turn the Power on While holding down [OSC2 SYNC] [-12dB/-24dB] and  
[FILTER TYPE]
2. Test mode is now in operation and the memory test begins.

The Tests are as follows

1. Memory Test
2. [1] MIDI Test
3. [2] Switch and LED test
4. [3] Adjusting Bender and MOD
5. [4] Adjusting Ribbon sensor
6. [5] A/D test
7. [6] Hold pedal test
8. [7] LCD test
9. [8] Sound Test

Exiting a test

Press the number button to quit the current test and start another test.
For the SW&LED test press the number button while holding down The  
[WRITE] button.

Exiting the test mode

(When the test is SW&LED, exit it)
Press [SHIFT/EXIT], Then "Are you sure?' is displayed.
Press [WRITE] to exit the test mode, then factory data will be loaded.



4. Adjusting Bender & Mod
On the Display you will have "[3] Bend Mod ??? ???"
(where ??? is the Hex value of the bender and mod)
Push the bender lever left fully and gradually return it to the  
original position.
Press the [LOWER] button.
Push the bender lever rightward fully and then gradually return it to  
the original position.
Press the [UPPER] button.
Push the bender lever to the MOD position and then gradually return  
it to the original position.
Press the [KEY MODE] button
Then an '*' appears press the [UP] button then the '*' changes to a  
'<->' mark

Moving the bender you should get these readings, left -256 center 0  
right 255
Moving the bender into the MOD position it should go up to 127 and  
then return to 0.
Now if the above things doesn?t happen, press the [3] button and  
readjust, if still not correct, take the keyboard to Roland service,  
as there could be a problem with either the bender unit itself, or  
some of the IC's could need to be replaced.
******************

And this is Factory reset:

***********************
Make sure the unit is on
Hold down [SHIFT] [EXIT] and press [INIT/UTIL] (7). The indicator  
will light
Press [INIT/UTIL] severval times to access the "Initialize [WRITE]" page
Use [DOWN/UP] to select the type of data to be initialized ("FACTORY  
PRESET" for everything)
Press [WRITE]

Result: All user patches, user performances, patterns, motion  
control, and system settings will be returned to their factory settings.

*****************

You can try it. After this reload again your data.

Good luck!

Daniel Forro
Show quoted textHide quoted text
On 4 Oct 2010, at 11:57 PM, Bakis Sirros wrote:

> hi lists,
>
> i recently got a 'battery low' message in my jp8000, so, today, i  
> changed the battery (with the correct type of course). it was an  
> easy process and was careful not to touch other electronics inside  
> the machine. i also used midi-ox to dump all the sounds and after  
> replacing the battery i reloaded all info in the machine with no  
> problem.
> but, now, the pitchbend does not work (it works, but has a very  
> limited range of less than a semitone) plus the 'lfo 2' section  
> does not work (the 'lfo 2' does not affect pitch or filter or amp),  
> and the ribbon controller affects parameters but is only sensitive  
> to tough (like an on-off switch) but not position as it also was...
>
> i suspect something from the controller section left of the  
> keyboard is damaged or disconnected... (i did the mistake and put  
> the upside-down jp800 in a hard surcface when i was changing the  
> battery...)
>
> any further ideas / help please?
>
> many thanks in advance,
>
> best regards,   :-)
> Bakis.
>
>
> Bakis Sirros - Parallel Worlds / Interconnected / Memory Geist
> [Doepfer_a100] group owner
> www. parallel - worlds - music. com
> www. myspace. com/ parallelworldsmusic
> www. myspace. com/ interconnectedmusic
> www. myspace. com/ memorygeist
> www. DiN. org. uk
> www. musicamaximamagnetica. com
> www. vu-us. com

Re: problem with JP-8000, pitchbend /lfo 2 section.

2010-10-04 by Bakis Sirros

ok, problem solved.

it just needed the test and set procedure for the bender and ribbon controller, described in the service manual.


Bakis Sirros - Parallel Worlds / Interconnected / Memory Geist
[Doepfer_a100] group owner
www. parallel - worlds - music. com
www. myspace. com/ parallelworldsmusic
www. myspace. com/ interconnectedmusic
www. myspace. com/ memorygeist
www. DiN. org. uk
www. musicamaximamagnetica. com
www. vu-us. com


--- On Mon, 10/4/10, Bakis Sirros <synth_freak_2000@...> wrote:
Show quoted textHide quoted text
> From: Bakis Sirros <synth_freak_2000@...>
> Subject: problem with JP-8000, pitchbend /lfo 2 section.
> To: "vintagesynthrepair" <vintagesynthrepair@yahoogroups.com>, jp8000@yahoogroups.com
> Date: Monday, October 4, 2010, 5:57 PM
> hi lists,
> 
> i recently got a 'battery low' message in my jp8000, so,
> today, i changed the battery (with the correct type of
> course). it was an easy process and was careful not to touch
> other electronics inside the machine. i also used midi-ox to
> dump all the sounds and after replacing the battery i
> reloaded all info in the machine with no problem.
> but, now, the pitchbend does not work (it works, but has a
> very limited range of less than a semitone) plus the 'lfo 2'
> section does not work (the 'lfo 2' does not affect pitch or
> filter or amp), and the ribbon controller affects parameters
> but is only sensitive to tough (like an on-off switch) but
> not position as it also was...
> 
> i suspect something from the controller section left of the
> keyboard is damaged or disconnected... (i did the mistake
> and put the upside-down jp800 in a hard surcface when i was
> changing the battery...)
> 
> any further ideas / help please?
> 
> many thanks in advance,
> 
> best regards,   :-)
> Bakis.
> 
> 
> Bakis Sirros - Parallel Worlds / Interconnected / Memory
> Geist
> [Doepfer_a100] group owner
> www. parallel - worlds - music. com
> www. myspace. com/ parallelworldsmusic
> www. myspace. com/ interconnectedmusic
> www. myspace. com/ memorygeist
> www. DiN. org. uk
> www. musicamaximamagnetica. com
> www. vu-us. com
> 
> 
>       
>

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