RF interference--I swear I can hear radio Tokyo!

[acidblue]

I have a couple of fuzz/distortion circuits on breadboard that when I tested them I can hear a radio show in the background
pretty darn clearly I  might add and yes it sounds like Japanese.

Is this pretty normal for a bread boarded circuit?
I assume the RF interference will go away when I put them into a metal enclosure.
Should I take any precautions other than grounding the enclosure?


Just thought I should ask.

[jasperoosthoek]

Sumimasen

No actually that's very normal. My old tube amp picked up radio signals all the time. Same for my Fuzz Face. With my separated power supply and all effects in metal boxes I never hear radio anymore. It did sounded like German btw . Start considering grounding if it doesn't go away when you put it in a box.

[chi_boy]

I'm playing with a white noise project on the breadboard and I could swear I hear a guy talking behind the noise. I find it creepy and it makes the hair on the back of my neck stand up.

[petemoore]

  The Fuzzface has the ability to tune to a different time dimension.
  Radio voice-narrative so profoundly anti-commie and racist it had to be from the 60's.
  It had the perfect timing to fit the record I was making and the 'radio-fade-in' effect matched the placement-times of the song, really helped out the intro...kept, brought up in the mix.
  Australia and what sounds like SSB was also available, I used Q2base as antenna base, other points worked well also, 6'' wire worked fine [this was was a FF on the testjig. 
  Amazing reception ability, just kinda wide on the reception band is all [it's like auto-control/outta control other than the antenna 'fix. 

[Philippe]

The Fuzzface has the ability to tune to a different time dimension.

Decades ago, an acquaintance swore that he heard the Hindenburg zeppelin/crash being broadcast live over the radio while he was playing his old Arbiter FF through a Plexi...he also mentioned that this experience was preceeded by some really good 'shrooms' + a 5th of Mescal.

[jasperoosthoek]

I'm desinging a Fuzz around Soviet tunnel diodes. The type number is in cyrillic... (The old Russian ones are relatively cheap, that's why I use em ).

Do I have to expect commie radio interference? Comrades! (what was that?)

[rousejeremy]

Every Fuzz circuit I have built here in Toronto picks up Chinese radio before I wire it into an enclosure, and all without a Burst Button. It's basically a sign that it works.

[acidblue]

Decades ago, an acquaintance swore that he heard the Hindenburg zeppelin/crash being broadcast live over the radio while he was playing his old Arbiter FF through a Plexi...he also mentioned that this experience was preceeded by some really good 'shrooms' + a 5th of Mescal.

Ahh yes I remember 'shrooms.
Thanks for the input guys.

I Just don't have any enclosures ATM so I'm gonna have to play over the Japanese voices.
Japan Town isn't too far from where I am, So it's probably some local radio show.
I doubt I'm picking up short wave from Tokyo, although you never know  

[jasperoosthoek]

Where do you live if I may ask? The direct flight from SF to Tokyo I took earlier this year was 11 hours.

[soupbone]

I don't know if this will work for what you've got,but I was having radio signals coming through my Digitech Whammy Pedal.I called Digitech and they said to use a 220pf cap from the input jack to ground.I don't know if that helps

[davidallancole]

I don't know if that size is correct or not, probably is if Digitech said to do it, but it will filter out the rf signals that the guitar/cable combination can pick up.  I once picked up a short wave radio station on my guitar.  I live in Saskatchean Canada and the station was in Michigan.

For an open house at school one time, I was going to build an AM demodulator because my buddy was building an AM modulator.  I could never get it to work, so I decided to built a distortion pedal instead.  Low and behold, when I fired it up and stopped playing, I could hear my buddys AM radio perfectly clear through my little distortion pedal.  I built two things in one!

The long and short is yes you can pick up radio signals in your guitar equipment and yes I wouldn't be surprised if you picked something up from Japan.  Thats just me, but the ham guys always surprise me with what they can pickup.

[PRR]

> I assume the RF interference will go away when I put them into a metal enclosure.

Find a car with a radio. Put it on a weak station.

Drive it under or through a bridge, or a heavy-metal parking garage. Depending how "enclosed" you get, the radio signal will fade.

Tin-foiling 99% of a cardboard box will knockdown radio pretty good. (Usually to the point that RF coming in the in/out jacks is the next problem.)

I've used cookie-sheets and cake pans around breadboards as a quick-check to whether it was the exposed circuits or stuff coming in the in/out leads. You do have to get a 90+% enclosure to do much good.

Guitar inputs are classic RF detectors. Use Fender's plan: a 34K series resistor to a 100pFd shunt cap to ground. (Fender used the 100pFd input of a 12AX7 tube.) This passes audio fine but puts the AM band way down.

You don't have to cut RF to zero: typically there's a diode threshold like 0.6V. A 0.9V RF signal will spew 0.3V of audio, which is pretty loud. A 0.4V RF signal is below threshold and no audio comes out.