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Roland JX3P Faulty

Roland JX3P Faulty

2012-12-20 by Nick

Hello all, Im a newb here and have re-ignited my long since dormant love of synths & electronics, so finding this group is great! Id like to buy a faulty JX3P from ebay and need some advice on the problem & see if anyone can advise.

The fault is that only the first bank (bank A) of preset sound buttons work - it is not possible to select the second bank of preset buttons (bank B) or the bank of buttons (bank C/D) that control the various functions of the sound editor/mapper.

Should I purchase & indulge? I would say my knowledge is intermediate and I do not have a scope now as I sold it years ago, maybe time to get another one? .. are those cheap nano scopes any good?

Any info would be great.

Best regards & thanks,
Nick

Re: Roland JX3P Faulty

2012-12-20 by Nick

Oh, I will just add that apart from the aforementioned faults, the rest of the synth works fine - keyboard, audio etc. Thanks

--- In vintagesynthrepair@yahoogroups.com, "Nick" <mckenzie126@...> wrote:
Show quoted textHide quoted text
>
> Hello all, Im a newb here and have re-ignited my long since dormant love of synths & electronics, so finding this group is great! Id like to buy a faulty JX3P from ebay and need some advice on the problem & see if anyone can advise.
> 
> The fault is that only the first bank (bank A) of preset sound buttons work - it is not possible to select the second bank of preset buttons (bank B) or the bank of buttons (bank C/D) that control the various functions of the sound editor/mapper.
> 
> Should I purchase & indulge? I would say my knowledge is intermediate and I do not have a scope now as I sold it years ago, maybe time to get another one? .. are those cheap nano scopes any good?
> 
> Any info would be great.
> 
> Best regards & thanks,
> Nick
>

Re: [vintagesynthrepair] Re: Roland JX3P Faulty

2012-12-20 by Jez

I'd test it properly first before buying just to make sure it's not got anything else wrong with it - the bank switching issue may just be all the seller has managed to find wrong with it.

But it sounds OK, and it sounds like it just has a switch problem. If you can select all 8 patches in bank A, you should find you can select B to D via midi (I'd guess the midi implementation of a JX3P allows this, though it is an early MIDI implementation, and the MIDI is extremely limited)

So it should jusy be a matter of fixing the switches.

Mind you - programming it won't be possible unless you do.
Show quoted textHide quoted text
On Thu, Dec 20, 2012 at 3:41 PM, Nick <mckenzie126@...> wrote:
Oh, I will just add that apart from the aforementioned faults, the rest of the synth works fine - keyboard, audio etc. Thanks

--- In vintagesynthrepair@yahoogroups.com, "Nick" wrote:
>
> Hello all, Im a newb here and have re-ignited my long since dormant love of synths & electronics, so finding this group is great! Id like to buy a faulty JX3P from ebay and need some advice on the problem & see if anyone can advise.
>
> The fault is that only the first bank (bank A) of preset sound buttons work - it is not possible to select the second bank of preset buttons (bank B) or the bank of buttons (bank C/D) that control the various functions of the sound editor/mapper.
>
> Should I purchase & indulge? I would say my knowledge is intermediate and I do not have a scope now as I sold it years ago, maybe time to get another one? .. are those cheap nano scopes any good?
>
> Any info would be great.
>
> Best regards & thanks,
> Nick
>




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Re: Roland JX3P Faulty

2012-12-20 by Grant B

Probably crack on the board. Fixed lots of those, not too hard at all if 
you have a meter and some free time. Also could be a logic chip, should 
not be hard to replace.

Re: Roland JX3P Faulty

2012-12-21 by Nick

Thanks for the advice. The seller added that now no preset/bank buttons work at all after he tested it again.
--- In vintagesynthrepair@...m, Jez <jezosaurus@...> wrote:
Show quoted textHide quoted text
>
> I'd test it properly first before buying just to make sure it's not got
> anything else wrong with it - the bank switching issue may just be all the
> seller has managed to find wrong with it.
> 
> But it sounds OK, and it sounds like it just has a switch problem. If you
> can select all 8 patches in bank A, you should find you can select B to D
> via midi (I'd guess the midi implementation of a JX3P allows this, though
> it is an early MIDI implementation, and the MIDI is extremely limited)
> 
> So it should jusy be a matter of fixing the switches.
> 
> Mind you - programming it won't be possible unless you do.
> 
> 
> 
> On Thu, Dec 20, 2012 at 3:41 PM, Nick <mckenzie126@...> wrote:
> 
> > Oh, I will just add that apart from the aforementioned faults, the rest of
> > the synth works fine - keyboard, audio etc. Thanks
> >
> > --- In vintagesynthrepair@yahoogroups.com, "Nick" <mckenzie126@> wrote:
> > >
> > > Hello all, Im a newb here and have re-ignited my long since dormant love
> > of synths & electronics, so finding this group is great! Id like to buy a
> > faulty JX3P from ebay and need some advice on the problem & see if anyone
> > can advise.
> > >
> > > The fault is that only the first bank (bank A) of preset sound buttons
> > work - it is not possible to select the second bank of preset buttons (bank
> > B) or the bank of buttons (bank C/D) that control the various functions of
> > the sound editor/mapper.
> > >
> > > Should I purchase & indulge? I would say my knowledge is intermediate
> > and I do not have a scope now as I sold it years ago, maybe time to get
> > another one? .. are those cheap nano scopes any good?
> > >
> > > Any info would be great.
> > >
> > > Best regards & thanks,
> > > Nick
> > >
> >
> >
> >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
>

Re: Roland JX3P Faulty

2012-12-21 by Nick

I think the switching matrix goes straight to the IC-1 cpu.

--- In vintagesynthrepair@yahoogroups.com, "Nick" <mckenzie126@...> wrote:
Show quoted textHide quoted text
>
> Thanks for the advice. The seller added that now no preset/bank buttons work at all after he tested it again.
> --- In vintagesynthrepair@yahoogroups.com, Jez <jezosaurus@> wrote:
> >
> > I'd test it properly first before buying just to make sure it's not got
> > anything else wrong with it - the bank switching issue may just be all the
> > seller has managed to find wrong with it.
> > 
> > But it sounds OK, and it sounds like it just has a switch problem. If you
> > can select all 8 patches in bank A, you should find you can select B to D
> > via midi (I'd guess the midi implementation of a JX3P allows this, though
> > it is an early MIDI implementation, and the MIDI is extremely limited)
> > 
> > So it should jusy be a matter of fixing the switches.
> > 
> > Mind you - programming it won't be possible unless you do.
> > 
> > 
> > 
> > On Thu, Dec 20, 2012 at 3:41 PM, Nick <mckenzie126@> wrote:
> > 
> > > Oh, I will just add that apart from the aforementioned faults, the rest of
> > > the synth works fine - keyboard, audio etc. Thanks
> > >
> > > --- In vintagesynthrepair@yahoogroups.com, "Nick" <mckenzie126@> wrote:
> > > >
> > > > Hello all, Im a newb here and have re-ignited my long since dormant love
> > > of synths & electronics, so finding this group is great! Id like to buy a
> > > faulty JX3P from ebay and need some advice on the problem & see if anyone
> > > can advise.
> > > >
> > > > The fault is that only the first bank (bank A) of preset sound buttons
> > > work - it is not possible to select the second bank of preset buttons (bank
> > > B) or the bank of buttons (bank C/D) that control the various functions of
> > > the sound editor/mapper.
> > > >
> > > > Should I purchase & indulge? I would say my knowledge is intermediate
> > > and I do not have a scope now as I sold it years ago, maybe time to get
> > > another one? .. are those cheap nano scopes any good?
> > > >
> > > > Any info would be great.
> > > >
> > > > Best regards & thanks,
> > > > Nick
> > > >
> > >
> > >
> > >
> > >
> > > ------------------------------------
> > >
> > > Yahoo! Groups Links
> > >
> > >
> > >
> > >
> >
>

Re: [vintagesynthrepair] Re: Roland JX3P Faulty

2012-12-22 by Paul Cunningham

Could be. Definitely worth checking for cracks in the pc boards on those. They are common and can cause all kinds of sporadic problems. It must be something to do with how they are mounted to the case that causes them to get cracked then they keyboard is dropped. -pc
Show quoted textHide quoted text
On Dec 21, 2012, at 11:10 AM, Nick wrote:

> I think the switching matrix goes straight to the IC-1 cpu.
> 
> --- In vintagesynthrepair@yahoogroups.com, "Nick" <mckenzie126@...> wrote:
>> 
>> Thanks for the advice. The seller added that now no preset/bank buttons work at all after he tested it again.
>> --- In vintagesynthrepair@yahoogroups.com, Jez <jezosaurus@> wrote:
>>> 
>>> I'd test it properly first before buying just to make sure it's not got
>>> anything else wrong with it - the bank switching issue may just be all the
>>> seller has managed to find wrong with it.
>>> 
>>> But it sounds OK, and it sounds like it just has a switch problem. If you
>>> can select all 8 patches in bank A, you should find you can select B to D
>>> via midi (I'd guess the midi implementation of a JX3P allows this, though
>>> it is an early MIDI implementation, and the MIDI is extremely limited)
>>> 
>>> So it should jusy be a matter of fixing the switches.
>>> 
>>> Mind you - programming it won't be possible unless you do.
>>> 
>>> 
>>> 
>>> On Thu, Dec 20, 2012 at 3:41 PM, Nick <mckenzie126@> wrote:
>>> 
>>>> Oh, I will just add that apart from the aforementioned faults, the rest of
>>>> the synth works fine - keyboard, audio etc. Thanks
>>>> 
>>>> --- In vintagesynthrepair@yahoogroups.com, "Nick" <mckenzie126@> wrote:
>>>>> 
>>>>> Hello all, Im a newb here and have re-ignited my long since dormant love
>>>> of synths & electronics, so finding this group is great! Id like to buy a
>>>> faulty JX3P from ebay and need some advice on the problem & see if anyone
>>>> can advise.
>>>>> 
>>>>> The fault is that only the first bank (bank A) of preset sound buttons
>>>> work - it is not possible to select the second bank of preset buttons (bank
>>>> B) or the bank of buttons (bank C/D) that control the various functions of
>>>> the sound editor/mapper.
>>>>> 
>>>>> Should I purchase & indulge? I would say my knowledge is intermediate
>>>> and I do not have a scope now as I sold it years ago, maybe time to get
>>>> another one? .. are those cheap nano scopes any good?
>>>>> 
>>>>> Any info would be great.
>>>>> 
>>>>> Best regards & thanks,
>>>>> Nick
>>>>> 
>>>> 
>>>> 
>>>> 
>>>> 
>>>> ------------------------------------
>>>> 
>>>> Yahoo! Groups Links
>>>> 
>>>> 
>>>> 
>>>> 
>>> 
>> 
> 
> 
> 
> 
> ------------------------------------
> 
> Yahoo! Groups Links
> 
> 
>

Re: Roland JX3P Faulty

2012-12-22 by Grant B

Fri Dec 21, 2012 8:10 am (PST) . Posted by: "Nick" mckenzie126

> I think the switching matrix goes straight to the IC-1 cpu.

No way. There is a ton of logic in those old things for the I/O. Anyway, most of the logic chips are pretty common. I'm still betting on a cracked panel board.

Re: Roland JX3P Faulty

2012-12-22 by Nick Bell

Oh, I've quite possibly overlooked something on the schematics then? If you have time the service manual is here: http://fa.utfs.org/diy/jx3p/jx3p_schem.htm

Re: [vintagesynthrepair] Re: Roland JX3P Faulty

2012-12-22 by Peter Mörck

Suspect IC34 near CN6 on the mainboard (upper right part of the schematic).
Possibly IC46 near CN9 and CN10, but then it looks like you'd have keyboard problems too.
IC53 (only individual gates visible on schematic) also involved.

Or, perhaps simply a bad connector.

BR,
Peter
Show quoted textHide quoted text
  ----- Original Message ----- 
  From: Nick Bell 
  To: vintagesynthrepair@yahoogroups.com 
  Sent: Saturday, December 22, 2012 5:12 PM
  Subject: [vintagesynthrepair] Re: Roland JX3P Faulty


    

  Oh, I've quite possibly overlooked something on the schematics then? If you have time the service manual is here: http://fa.utfs.org/diy/jx3p/jx3p_schem.htm

Re: Roland JX3P Faulty

2013-01-06 by Nick

Hello all. Yep there were multiple hairline cracks, all fixed now with all control restored.

I do however need to replace the (Sharp)IR94558 op amp in the mixer section (IC1) as it's crackling. I can get a new Sharp IC but it's rather expensive. I'm inclined to stick with sharp but would anyone perhaps suggest using the cheaper JRC or the like?

Thx

--- In vintagesynthrepair@yahoogroups.com, Nick Bell  wrote:
Show quoted textHide quoted text
>
> Thanks all for your input, really helpful & appreciated. Will report back with any successful/unsuccessful repairs.
>

Re: [vintagesynthrepair] Re: Roland JX3P Faulty

2013-01-06 by jammie

the 4558 op is a very noisy opamp
you can change them for the tlo8/7 series dual opamps
is it a dip or a ziff 9pin ic
as in the korg dss1 they are ziff 9 pins
i exchanged mine for the ones used in the korg trinity the
UPC4570HA made by nec
jrc are a good make if you can source them
the 4558 has a very rubbish slew rate and are noisy
but becuase of this they make great fx pedals as fast transients can distort
Show quoted textHide quoted text
----- Original Message -----
From: Nick
Sent: Sunday, January 06, 2013 3:49 PM
Subject: [vintagesynthrepair] Re: Roland JX3P Faulty

Hello all. Yep there were multiple hairline cracks, all fixed now with all control restored.

I do however need to replace the (Sharp)IR94558 op amp in the mixer section (IC1) as it's crackling. I can get a new Sharp IC but it's rather expensive. I'm inclined to stick with sharp but would anyone perhaps suggest using the cheaper JRC or the like?

Thx

--- In vintagesynthrepair@yahoogroups.com, Nick Bell wrote:
>
> Thanks all for your input, really helpful & appreciated. Will report back with any successful/unsuccessful repairs.
>

RE: [vintagesynthrepair] Re: Roland JX3P Faulty

2013-01-06 by John Rose

I have just had a quick look in my box of opamps and have both the RC4558
and the MC1458 which are equivalent and I can get hold of these still for
pennies, but the suggestion that you look at the Ti TL opamps is worth
considering as they are not much more expensive and do have lower noise, I
used to reduce the noise in some of the old mixing desks.

 

Many thanks

 

John Rose

 

(www.astrodevelopments.com)
Show quoted textHide quoted text
From: vintagesynthrepair@yahoogroups.com
[mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of jammie
Sent: 06 January 2013 17:19
To: vintagesynthrepair@yahoogroups.com
Subject: Re: [vintagesynthrepair] Re: Roland JX3P Faulty

 

  

the 4558 op is a very noisy opamp

 

you can change them for the tlo8/7 series dual opamps

 

is it a dip or a ziff 9pin ic

 

as in the korg dss1 they are ziff 9 pins 

 

i exchanged mine for the ones used in the korg trinity the 

 


UPC4570HA made by nec


jrc are a good make if you can source them

 

the 4558 has a very rubbish slew rate and are noisy

 

but becuase of this they make great fx pedals as fast transients can distort


----- Original Message ----- 

From: Nick <mailto:mckenzie126@...>  

To: vintagesynthrepair@yahoogroups.com 

Sent: Sunday, January 06, 2013 3:49 PM

Subject: [vintagesynthrepair] Re: Roland JX3P Faulty

 

  

Hello all. Yep there were multiple hairline cracks, all fixed now with all
control restored.

I do however need to replace the (Sharp)IR94558 op amp in the mixer section
(IC1) as it's crackling. I can get a new Sharp IC but it's rather expensive.
I'm inclined to stick with sharp but would anyone perhaps suggest using the
cheaper JRC or the like?

Thx

--- In vintagesynthrepair@yahoogroups.com
<mailto:vintagesynthrepair%40yahoogroups.com> , Nick Bell wrote:
>
> Thanks all for your input, really helpful & appreciated. Will report back
with any successful/unsuccessful repairs.
>

RE: [vintagesynthrepair] Re: Roland JX3P Faulty

2013-01-06 by John Rose

If you have a problem getting them let me know as I can get hold of most items and am in the UK

 

Many thanks

 

John Rose

 

(www.astrodevelopments.com)
Show quoted textHide quoted text
From: vintagesynthrepair@yahoogroups.com [mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of Nick Bell
Sent: 06 January 2013 23:48
To: vintagesynthrepair@yahoogroups.com
Subject: RE: [vintagesynthrepair] Re: Roland JX3P Faulty

 

  

Thanks both - it's a dip, will prob try the TL's

best
Nick

Re: [vintagesynthrepair] Re: Roland JX3P Faulty

2013-01-07 by Nick Bell

Thanks John, that's really good to know. I found a few TLO72's on ebay.

Best
Nick




________________________________
Show quoted textHide quoted text
 From: John Rose <johnhenryrose@...>
To: vintagesynthrepair@yahoogroups.com 
Sent: Sunday, 6 January 2013, 23:59
Subject: RE: [vintagesynthrepair] Re: Roland JX3P Faulty
 

  
If you have a problem getting them let me know as I can get hold of most items and am in the UK
 
Many thanks
 
John Rose
 
(www.astrodevelopments.com)
 
From:vintagesynthrepair@yahoogroups.com [mailto:vintagesynthrepair@yahoogroups.com] On Behalf Of Nick Bell
Sent: 06 January 2013 23:48
To: vintagesynthrepair@yahoogroups.com
Subject: RE: [vintagesynthrepair] Re: Roland JX3P Faulty
 
  
Thanks both - it's a dip, will prob try the TL's

best
Nick

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