Vintage Synth Explorer Forums

bbspring wrote:None of the diagnostics involve the power supply, however. I think I may just take this instrument to a synth repair technician when I have the opportunity. I'll keep everyone posted.

Do you have a multimeter? If so, might as well take a gander yourself. If nothing else, it'll be a learning experience.

Yes check the PSU at least with a DMM (scope would be better to see if filter is working right), it's no harm to replace the filter cap there it's likely to be drying out at this stage. Don't worry about the diagnostics either. Those sockets you mentioned need repair/ replacement anyway.

I think if both of those repairs should be done anyway, and if you're lucky it will sort the crackling problem.

PS the PSU filter is a completely different thing to the audio filter

bbspring wrote:Rasputin, I checked under the synth for an external switch, and lo and behold there was one under the jack. As with the RZ-1, I used a screwdriver to switch the voltage to 120V. Thanks for the tip! That's one less thing to worry about.
Of course, I'm still having the crackly sound problem. It sounds like you and madtheory may be correct that the power supply is the problem. Also it does seem sensible to run the calibration procedure before doing anything else. Unfortunately, the service manual doesn't have any information about a calibration procedure. There are diagnostics procedures, some involving a floppy disk that I don't have. None of the diagnostics involve the power supply, however. I think I may just take this instrument to a synth repair technician when I have the opportunity. I'll keep everyone posted.

Hey bbspring,

Did you make any progress on this? Think I'm having the same problem, (actually on two different Fz-1's.)

I think I'm gonna replace my filter caps and go from there. Maybe rebuild my entire PSU while I'm down there.

Anybody see it wise to replace all the electrolytic caps while it's open? Any other ideas?

On another note, with some help from gmeredith I just cannibalized an iphone 4 to replace my LCD backlight with. Went pretty well. Big thanks to the Tasmanian.

morning guts wrote:
On another note, with some help from gmeredith I just cannibalized an iphone 4 to replace my LCD backlight with. Went pretty well. Big thanks to the Tasmanian.

No trouble getting the old EL panel out and replace it with the IPhone 4 backlight?

Changing a FZ-10m EL panel for a IPhone backlight is quite straight forward but with the FZ-1 I had to be very careful.

viewtopic.php?f=3&t=44276&start=90

Hi everyone, sorry I didn't see this post - I realize its very old, so forgive me.

All of the CZ/VZ/FZ series instruments have an anti-thump power-on circuit on the output - it's basically a relay that mutes the audio out when it gets switched on for a second or two, to stop a loud pop or thud destroying your mixing desk or amplifier.

My CZ101 had a nasty distortion sound coming from it one day, with crackles. It made it sound like a bad guitar cable was the culprit, which I tried fixing so many times until I found out that it was the relay. The contacts get dirty or wear out, and make a distorted sound, especially on lower frequencies. Makes it sound like a distortion pedal a little bit - an annoying fuzz in the background.

Try tapping the relay with a screwdriver while playing a note and see if it changes the sound. If it does, you should be able to get an easy replacement, they're a 12V or 5V relay

Hi,
It's 5VDC signal relay relay, I think.