Casio CZ/ VZ/ FZ - Pro Series

Hi all,

I recently got a CZ-101 for 200 euros from someone who was the first 
owner. Everything was suppose to be work, but of course the line select 
#1 light was dead, the volume slider causes cracking in the sound, it 
sometimes needs to be pushed down to hear something coming out and the 
display still stays on after switching it off.

I don't really mind about the dead line select light and the noisy 
volume slider but I am worried about the LCD that won't shutdown. At 
first, I thought it was normal, before adding 6 D batteries to preserve 
patches as I only had to disconnect the power supply but now I need to 
leave it connected or else it will drain the batteries.

I searched everywhere about this issue, I found other users who had this 
problem but I couldn't find any solution. Does anyone already 
experienced this issue ? Is there any known fix ? If not, do you think 
installing a backlit display could fix this power problem ?

Thanks in advance for any advice. I am really desperate to fix this 
little synth...

-- 
J\ufffdr\ufffdme

On 30/09/12 10:33, Jerome St-Pierre wrote:

> I searched everywhere about this issue, I found other users who had this
> problem but I couldn't find any solution. Does anyone already
> experienced this issue ? Is there any known fix ? If not, do you think
> installing a backlit display could fix this power problem ?

Must be some sort of power supply problem.  At a guess I'd say there's a 
switching transistor that has failed shorted.  Grab the service manual 
and check around the power switching circuitry.  There's all sorts of 
weirdassery going there involving flipflops and timing circuits.

When you turn the power on and off you should hear the output muting 
relay click on and off.  That indicated that the on/off latch and reset 
timer is *probably* okay.

-- 
Gordon JC Pearce MM0YEQ