MF103 vs audio interference/noise

Pewt · Post by **Pewt** » Mon May 18, 2009 2:13 pm

My MF-103 seems to pick up a lot of radio interference, and at certain points (esp. when drive is around 3 o clock or lower but output is up) it seems to have a lot of noise as well. I think it might be where I live (I do sometimes pick up radio on guitar amps as well), but my Little Phatty sits right next to the Fooger and is rock solid- any ideas?

CTRLSHFT · Post by **CTRLSHFT** » Mon May 18, 2009 6:28 pm

Pewt wrote:My MF-103 seems to pick up a lot of radio interference, and at certain points (esp. when drive is around 3 o clock or lower but output is up) it seems to have a lot of noise as well. I think it might be where I live (I do sometimes pick up radio on guitar amps as well), but my Little Phatty sits right next to the Fooger and is rock solid- any ideas?

are you using the same cable between the two of em? maybe try TRS, or shortening the length of your TS cable. could just be the area you live in too if the signal passing through is extremely strong. i'd say also try swapping the cable out for a different one if anything. could be a shielding issue.

DontBelievetheHype · Post by **DontBelievetheHype** » Tue May 19, 2009 8:44 am

Moogerfoogers are prone to various causes of noise. Mine stay in a bypass looper, so when they're noisy it's only a minor issue since they're out of the chain when not engaged. I live in an underpowered old house with noisy wiring.

If you're experiencing rf interference, I'd recommend shielding the inner panels. I've read of other people having good results from copper shielding the inside of their 'foogers, and Im pretty sure you can pick copper foil up from most hardware stores relatively cheap.

Zeta Madness · Post by **Zeta Madness** » Tue Jun 23, 2009 10:01 pm

I just shielded my MF-103 with copper tape, plugged it in, an got an oldies station when I put my hand close to the panel... I turned it into a radio! The fix was simple, just soldered in a 1uF cap between the shield and any connection to the minus rail in the pedal. That "grounds out" only the high frequency stuff (ie. radio waves).

Incidentally, I discovered my MF-101 had a ground wire at the footswitch connecting the minus rail to the panel, which I also replaced with a cap. It seemed to clear up some of the ground loop-sounding hum that was driving me nuts. I've read others have had hum probs with that pedal, maybe they can have a look if the panel is likewise connected to the rail... Grounding and shielding is a black art...

Next one I shield, I'll post some pics if people are interested.

brain_11 · Post by **brain_11** » Wed Jun 24, 2009 6:09 pm

Yes, please post some pics!

screamingstrings76 · Post by **screamingstrings76** » Wed Jul 01, 2009 12:21 pm

yes please pictures! ive got 3 foogers and they seem to get noise from time to time in the house (not so much at the practice space). it would be awesome to make them quiet!

mgrfgrmadness · Post by **mgrfgrmadness** » Wed Jul 01, 2009 3:06 pm

i live in an old house with bad wiring and i live right near a christian rock radio station (it's torture when i'm recording), but it's my 101 that picks up most of the radio, so i put tin foil on the output cable and that stops it

Zeta Madness · Post by **Zeta Madness** » Thu Jul 09, 2009 8:59 pm

http://s556.photobucket.com/albums/ss2/ ... =slideshow

hope the photobucket links works

Zeta Madness · Post by **Zeta Madness** » Thu Jul 09, 2009 9:16 pm

I've also had back luck with hum and noise if I used anything other than the cheapie wall warts. Forget about daisy chaining moogers together on one supply! Check this article out on ground loops...

http://www.geofex.com/Article_Folders/Spyder/spyder.htm

I tried some inexpensive "one spot" - type switching regulator wall warts, and that gave me noise too. I'll have to open one up, but I suspect there is no isolation between the 120 VAC and the DC output, so I was getting that ground loop again from the supply.

I'm going to build a 4 output individually-isolated power supply with some toroidal transformers and 7812 voltage regs and see how that works! Isn't analog fun!!!

Voltor07 · Post by **Voltor07** » Thu Jul 09, 2009 10:42 pm

Zeta Madness wrote:I've also had back luck with hum and noise if I used anything other than the cheapie wall warts. Forget about daisy chaining moogers together on one supply! Check this article out on ground loops...

http://www.geofex.com/Article_Folders/Spyder/spyder.htm

I tried some inexpensive "one spot" - type switching regulator wall warts, and that gave me noise too. I'll have to open one up, but I suspect there is no isolation between the 120 VAC and the DC output, so I was getting that ground loop again from the supply.

I'm going to build a 4 output individually-isolated power supply with some toroidal transformers and 7812 voltage regs and see how that works! Isn't analog fun!!!

Very nice project! Good luck with that. I may try building one someday...when I can justify it.

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MF103 vs audio interference/noise

MF103 vs audio interference/noise

Re: MF103 vs audio interference/noise

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