Vintage Synth Repair

Hello!

I just bought a Roland Alpha Juno 2 and noticed that the backlit of display
is not working. Actually I just noticed that the display was supposed to
have backlit when the keyboard was in the very dark because there is still
some weak light.

I've found a message in Analogue Heaven about this but no answer. Does
anybody knows how to fix it?

Thanks!
Arnaldo.

Hi Arnaldo,

> I just bought a Roland Alpha Juno 2 and noticed that the backlit
> of display
> is not working. Actually I just noticed that the display was supposed to
> have backlit when the keyboard was in the very dark because there is still
> some weak light.
>
> I've found a message in Analogue Heaven about this but no answer. Does
> anybody knows how to fix it?

There's an EL foil behind the display glass that's failing. They fade out
over time (10 years or so) but can normally be replaced without fully
disassembling the display. It normally has 2 contacts and operates on high
AC voltage, >= 100V / 400Hz or so. This can be replaced today.

Don't know about neither Brazil nor the Alpha Juno 2, but if you desolder &
remove & measure the old foil, there are places that can provide a
compatible replacement. Even in various colours... unfortunately, I know
only European sources. You might try

  http://members.aon.at/virtual-music/e_products.htm

Alexander's continually searching for new displays, so he might be
interested in cooperating with you on that. Then there's

  http://www.midi-rakete.de

with some details on the theme who can provide custom-size foils at decent
prices. They look slightly "homemade", though :-). As another source,
there's

  http://www.backlights.co.uk/

but their prices are way higher.

Of course, there's my own page about adding/replacing backlight in my PPG
Waves at

  http://www.hermannseib.com/english/synths/ppg/wavedis.htm
  http://www.hermannseib.com/english/synths/ppg/wavediso.htm

but that's highly specific and surely doesn't match your Roland.

Don't know about the Americas, as said, but if you go on the hunt with
keywords like "EL foil replacement" or "electroluminescent" or whatever
that's in your native language, you might find something nearer to you.

Of course, nobody says you can't replace the complete display, but that's
normally overkill...

Bye,

  Hermann