Roland Fr3xb problem

[Pipemajor]

I have a Roland Fr3xb.
The other day I had been playing for about 20 minutes when the G4 button became silent. The tune I was playing at the time (Alpine Slopes) has multiple G triplets and it was only when I started playing this tune that the problem appeared. All the other notes worked fine. I tried selecting a different octave for the G4 button but none worked which would suggest it was a problem with the button itself.
After about 5 minutes the note the re-appeared and worked fine until I tried playing repeated Gs when it went again. This continued until I finally gave up and stopped playing.
I was unable to play it for the next couple of days but last night I tried again and started with "Alpine Slopes" and it worked properly I continued playing and again after about 20 minutes the G4 button fell silent, repeating the same results as last time, coming back after about 5 minutes then going again.
I haven't tried the midi out yet, so I can't totally rule out an electronic problem .
I would be grateful for any comments/advice from the experts here but I think I'm going to have to see if there is a Roland service centre near here.

 

[Ventura]

you are correct to proceed with testing the G4 as a MIDI out event
the next time it happens, then you will know if it is a software glitch
of the internal sound module, or an intermittent physical/software problem
of the entire system

 

[Pipemajor]

Thanks Ventura, I checked it using the Midi out and got the same problem although it now seems to be happening quicker, so I would think this would point to switch problem.

 

[Ventura]

i do not know exactly the physical switching system used on the
button treble version, but the keyboard versions used the rubbery top-hat style
"switches" on the long circuitboard under the keys

they tested them on machines a million strokes
BUT
tested them lying flat

we play them up and down,

and so they never noticed that the top-hats distended their base a
tiny bit, just enough to allow cat hairs and such to slip under the
edges (fed by gravity) and eventually interfere with switching integrity

i do not know if they ever corrected this, or if your 3x would have a similar
weakness in the design, but it is worth a look if you can dis-assemble it
just enough to look under the keyboard and check under that switch for dirt/dust/etc.

 

[pentaprism]

this would point to switch problem.

Bummer!

they tested them on machines a million strokes
BUT
tested them lying flat

we play them up and down,

I don't think it has to do with testing flat and playing up and down. On my wife's Roland KR-107 piano, when it was about 12 yrs old, some of the keys had uncontrollable volume (each switch under the key has 2 contacts for velocity sensitivity). I ended up replacing the switches under the keys (all 88 of them). I think Roland must have tested the switches laying flat a million strokes. But I don't think my wife had hit the keys a million times in 12 years and I know she hadn't played them up and down.

On something like the Roland KR-107, cleaning the contacts can fix the problem. But I don't know if there is a way to access the contacts on a V-accordion.

 

[Pipemajor]

One thing I neglected to test was the 5th row G button.
I tried this evening and found that the 5th row G does indeed sound when the 2nd row G is silent.
I think this would point to the switch being the problem.
Just need to find out how to remove the buttons and the keyboard case to check the switch.

 

[davidplaysaccordion]

Systems with a lot of contacts often use a multiplexed array to reduce the number of wires needed. Each switch is a row and column on a grid pattern array which the electronics polls in turn. There would be a diode across each junction to prevent back flow to other nodes on the same row/column so it is possible that the diode at that junction (assuming it uses this system) is going out.

 

[Pipemajor]

Just a quick update. I've found a Roland accredited repairer (EMS) in Southend on Sea which is not too far from me who is confident he can fix it so it is now with him and he expects I can have it back in about 3/4 weeks.

 

[JerryPH]

That is indeed good news!