Yahoo Groups archive

Emax

Index last updated: 2026-04-28 23:23 UTC

Message

Re: Five top keys fault

2012-07-10 by jaumemod

REPAIRED!

I was the bad solder point at G#5 contact board.

Thx a lot Jose and Jammie.


--- In emax@yahoogroups.com, "jaumemod" <jaumemod@...> wrote:
>
> 
> The bad solder point corresponds to G#5... I'll tell you something...
> --- In emax@yahoogroups.com, "jammie" <jammie.emma@> wrote:
> >
> > yes a cold solder joint will do it as they are done in banks if one goes the whole octave will go
> > 
> > if it was just one key then i would of said dirt on the spring contact or the spring has snpped or fallen ot which also does happen
> >   ----- Original Message ----- 
> >   From: jaumemod 
> >   To: emax@yahoogroups.com 
> >   Sent: Monday, July 09, 2012 11:14 PM
> >   Subject: [emax] Re: Five top keys fault
> > 
> > 
> >     
> >   The maneuver I performed for it working again was to raise the contact spring with a nylon stick while pressing one of five keys on the MIDI master keyboard. Then everything was returning to work.
> > 
> >   This must create a bridge between contacts or something similar
> > 
> >   Ouuuuk! For the moment I traced the contact ways to contact key and I find a bad solder point....perhaps it's the cause which when I turn upright sampler all faults again.
> > 
> >   Tomorrow I ll put a bit solder....I'll tell you something...
> > 
> >   THX a lot
> > 
> >   --- In emax@yahoogroups.com, "jammie" <jammie.emma@> wrote:
> >   >
> >   > i agree i recon its a diode or the return circuit to the scanner cpu
> >   > 
> >   > the scanner cpu gets pulse signals from when a key is pressed0volts to 5volts to zero volts like a half square wave cycle
> >   > 
> >   > he says he is getting voltage across the diode 5v when key is pressed
> >   > 
> >   > so to me the keys is making a circuit as tested but that siganl is not getting back to the cpu scanner
> >   > 
> >   > now its either the wire for that octave is damaged or there is a broken track 
> >   > 
> >   > he needs to trace the tracks from that octave and see if he is getting continuity to the header cable if he is then its at the mother board end 
> >   > 
> >   > as the scanner cpu is not recieving the trigger pulses for that octave
> >   > ----- Original Message ----- 
> >   > From: emax_dx5 
> >   > To: emax@yahoogroups.com 
> >   > Sent: Monday, July 09, 2012 6:09 PM
> >   > Subject: [emax] Re: Five top keys fault
> >   > 
> >   > 
> >   > 
> >   > 
> >   > Yeah I don't discard it at all, but three 1125's I had to deal with were completely dead when failing. Talking about a failing octave (just that) I would go for traces or diodes (appart from all suggested above). Those keyb pcbs are prone to crack traces . 
> >   > 
> >   > --- In emax@yahoogroups.com, "jammie" <jammie.emma@> wrote:
> >   > >
> >   > > actually i can be the scanner chip iv had it when you can play notes on kewyboard but when pressing buttons its arratic and jumps allover the place
> >   > > ----- Original Message ----- 
> >   > > From: emax_dx5 
> >   > > To: emax@yahoogroups.com 
> >   > > Sent: Monday, July 09, 2012 2:59 PM
> >   > > Subject: [emax] Re: Five top keys fault
> >   > > 
> >   > > 
> >   > > 
> >   > > I won't go for the MPU Scanner (IM386). When it fails, no button or key usually work.
> >   > > 
> >   > > You said you sent midi to the Emax and it made sound. Did you check the MIDI OUT commands the emax is sending? you can do it both with a Midi analyzer on your computer or using the function MIDI Scope. Check if it sends Key ON and OFF commands or not. If any of those cases:
> >   > > 
> >   > > Go to the keyboard Printed Circuit Board. ONce you already checked diodes, Check continuity on the traces involved with those keys (a multimeter will do the job). If a common ground trace is open, this fault uses to happen.
> >   > > 
> >   > > hope it helps.
> >   > > 
> >   > > Best.
> >   > > Jose
> >   > > 
> >   > > 
> >   > > 
> >   > > 
> >   > > 
> >   > > [Non-text portions of this message have been removed]
> >   > >
> >   > 
> >   > 
> >   > 
> >   > 
> >   > 
> >   > [Non-text portions of this message have been removed]
> >   >
> > 
> > 
> > 
> >   
> > 
> > [Non-text portions of this message have been removed]
> >
>

Attachments

Move to quarantaine

This moves the raw source file on disk only. The archive index is not changed automatically, so you still need to run a manual refresh afterward.