My MF-104z Delay will no longer self-oscillate

djhendrix · Post by **djhendrix** » Tue Mar 25, 2008 9:35 am

Hello,

I'm not sure what happened...but it seems like the feedback knob only has a limited effect when the loop is on Internal. I can have it turned all the way up and still only get a few repeats. I remember having to REALLY Watch It when I had Feedback turned up that high.

I still have to watch it and the Loop Gain when I have it set to External Loop. Any ideas? Seems like maybe it is broken? If so, that would suck...because it was $700 and I haven't even had it a year

Bryan T · Post by **Bryan T** » Tue Mar 25, 2008 12:23 pm

Mine did the same thing last year. I sent it back to Moog and they fixed it. It has been fine ever since.

Here's the thread: http://moogmusic.com/forum/viewtopic.ph ... ight=delay

Bryan

mimich · Post by **mimich** » Sat Jun 07, 2008 6:00 am

Hello,

Mine did the same too. I was thinking about power supply problem (because switching it off and on sometimes correct the problem) but after opening the Moogerfooger what a surprise !
A 3 pins jumper selector on the left of the pedal, mounted on a second circuit board, is close touching the metal frame of the MF 104 Z

When he touch the frame completly there is no more repeat !
I just bend the pins to avoid any mechanical contact and no more problem since ...
Very disappointing for a Moog product

c7sus · Post by **c7sus** » Sat Jun 07, 2008 11:05 am

Thanks for the tip, mimich.

I addressed the issue with a small piece of business card stock and some electrical tape to hold it in place. 2 of the 3 pins had worn the paint right down to bare metal!

I thought it was a power supply issue all this time as well.

Bryan T · Post by **Bryan T** » Sat Jun 07, 2008 11:23 am

Can you be a little more specific about what needs to be done? Where is the second circuit board? How do you get to it?

Thanks,
Bryan

mimich · Post by **mimich** » Sat Jun 07, 2008 12:57 pm

On the left side (circuit board view) or on right side of the pedal in normal position.
You can see an extra bord with jumper ...
Isolate the pins from the metal frame or bend them like on the photo

cl516 · Post by **cl516** » Sat Jun 07, 2008 1:05 pm

what's the official word on opening these up ourselves?
does it void any support?

is it simply as easy as 'bending' that piece?

thanks

mimich · Post by **mimich** » Sat Jun 07, 2008 1:19 pm

I suppose that officialy this void the waranty, and this is at your own risk, but you can just isolate the pins if you're affraid of bending the jumper.
4 screws to remove the right wood plate and an electrical tape ... or send back your moogerfooger to MoogMusic

latigid on · Post by **latigid on** » Sat Jun 07, 2008 4:51 pm

Well, you remove the sides to rackmount them, so hopefully it's still okay.

matt the fiddler · Post by **matt the fiddler** » Sat Jun 07, 2008 10:46 pm

a small post in note stuck to the medal on the inside is all it took for mine.. no lasting damage.. paper= excellent insulator

Bryan T · Post by **Bryan T** » Sun Jun 08, 2008 12:25 pm

It turns out that this is exactly what the problem with my delay has been. If the jumpers touch the casing, no delay. If they don't, it works as normal. I'll send a note to Ryan at Moog that this is what is going on. I'll see what he suggests as a fix.

Thanks for the thread!

Bryan

matt the fiddler · Post by **matt the fiddler** » Sun Jun 08, 2008 6:25 pm

I woudl not bend the pins BTW

Bryan T · Post by **Bryan T** » Sun Jun 08, 2008 7:22 pm

matt the fiddler wrote:I woudl not bend the pins BTW

Yeah, that seems like an accident waiting to happen. Either a broken solder joint, broken pin, or something else. I'll report back what Ryan suggests.

I'm just happy to be at the bottom of this, as the 104 is my favorite pedal. The intermittent problems were starting to sour my love for it.

Bryan

matt the fiddler · Post by **matt the fiddler** » Sun Jun 08, 2008 10:37 pm

IF I were a service tech, I would probably just Nip the Tip... You know about half off.

I wonder what function the jumper is playing.

Half of me wants to tweak the insides to mod them (I like turning and tweaking things, thus I like Moog Stuff).. but I dont' want to mess with the balance that is there on the internal pots...

While we are at it, any one know what each of the internal pots controls, or internal jumpers?

mimich · Post by **mimich** » Mon Jun 09, 2008 2:53 am

Hello,

The best solution is to use closed jumper caps (2 for hiding the 3 pins) like the blue one on the photo ...