D*A*M Forum

I had a tech take a look at my CE-2 and turns out it was a grounding issue with one of the pots that was killing the chorus fx.
A bit embarrassed I wasn't able to figure that out, but at least it's back in working condition. Thanks for all the troubleshooting suggestions.

hah! had that same sort of prob with a TS-9! but there the short took out one of the divider resistors in the power supply for the 4.5V bias supply...

...And i had it today in a Double sound wah, one of the wires to the pot was not cut at the lug, and touching the pot. Made it work backwards and other wierd stuff,
i was about to go batsh*t crazy before i figured out what was wrong .

Hagstrom71 wrote: ↑Sat May 04, 2019 6:29 pm I had a tech take a look at my CE-2 and turns out it was a grounding issue with one of the pots that was killing the chorus fx.
A bit embarrassed I wasn't able to figure that out, but at least it's back in working condition. Thanks for all the troubleshooting suggestions.

Don't be. I have an old analog delay that hasn't ever worked right. If I open it up, it works fine, but as soon as I put the case back together no delay.
It's been sitting in a box for years, but I took it out the other day to look at it and it turns out the input jack is grounding out on the case, Doh!

That's similar to what mine was doing! the pots were grounding out on the case.

Hi gang,

I have a japanese made flanger pedal that doesn't work. LED does light up but all I get is the bypass signal (zero effect whatsoever).
Should I measure the opamp voltage too? Does it include the MN300x chip voltage and MNxxxx clock driver?

Thanks very much!

OK so I went ahead a took some voltages on the RC4558P chip.
(EDIT: there's 2 of them but one is an LFO chip that seem to work ok, as pin 3 and 7 provide varying voltages from 2 to 7V)

Here's what I got on the "non LFO" 4558 chip:

Pin 1: can't get measurement, starts at around 3V then slowly goes down and stabilizes at around 0.4V
Pin 2: same
Pin 3: 4.9V
Pin 4: 0V
Pin 5: 4.9V
Pin 6: 8.9V
Pin 7: 8.7V
Pin 8: 8.9V

It looks fishy to me but I honestly don't know squat about ICs.
Is it good ?
Or should I replace it?
Or should I look for bad components next to it?
Or should I look elsewhere?

Thanks very much for the answer.

(BTW I wish I could open a new thread but as a new member I can not do that, so I'm hijacking this thread as the original poster asked about a solving problems on an old chorus which is quite similar to my old flanger).

Yup, that looks bad but do you have a name for this mystery flanger so I can see a schematic? Could be something around the chip causing it.

Thanks for the answer!
The Flanger in question is a "Guyatone PS004". Please let me know if you find something.