Vintage Synth Repair

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

From: Quazimodo

To: vintagesynthrepair@yahoogroups.com

Sent: Monday, July 16, 2012 7:53 PM

Subject: [vintagesynthrepair] Re: Backlight Revisited...

I was told that you cannot/should not measure the voltage with a meter... but to use an a/c checker, like the neon screwdriver, which does light! As the neon lights I can hear the transformer start to buzz.

There is one small transistor assocated with the transformer. Haven't checked it's temperature - should it be getting warm?

Also what should the frequency of the a/c output be?

Thanks for the suggestions guys.
TOM

--- In vintagesynthrepair@yahoogroups.com, NoëlBuhagiar wrote:
>
> Hi,
>
> You could have low voltage at step-up transformer output.
> Transformer could have developed shorted turns.
>
> Do the oscillator transistors get hot?
>
> Good luck,
> Noel
>
>
> From: Quazimodo
> Sent: Monday, July 16, 2012 6:52 PM
> To: vintagesynthrepair@yahoogroups.com
> Subject: [vintagesynthrepair] Backlight Revisited...
>
>
> Hi folks,
>
> I wonder if anyone has any ideas about this one.
>
> I bought a new backlight for this Korg Wavestation EX... it didn't work. I checked the pins on the power supply feeding it... and it lit up one of those neon A/C test screwdrivers.
>
> So I assumed the light was faulty and got a replacememt. Today I wired up the new backlight - on a loose wire, just to make sure it works and... nothing!
>
> I am getting power on the connector... and I have two backlights that don't light on it.
>
> Any ideas/suggestions please...?
> Cheers,
> TOM
>