Picking up radio signals.

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fretwire3d

New member
I live in a house built in 1910's, and the wiring isn't great. I keep on picking up radio signals on my guitar/effect/amp, and i didn't mind it for some tracks, but now my entire album has some radio signals. I have a stupid Signal Flex power supply for my effects and i've been blaming it for the radio signals. The radio signal really gets loud when i put on my dyna comp and reasonably wild when i put on the old big muff.

Where does the radio signal come from? (guitar, amp, grounds, effects...ect)
How do i correct it?
Would putting the amps through a power conditioner help?
 
fretwire3d said:
I live in a house built in 1910's, and the wiring isn't great. I keep on picking up radio signals on my guitar/effect/amp, and i didn't mind it for some tracks, but now my entire album has some radio signals. I have a stupid Signal Flex power supply for my effects and i've been blaming it for the radio signals. The radio signal really gets loud when i put on my dyna comp and reasonably wild when i put on the old big muff.

Where does the radio signal come from? (guitar, amp, grounds, effects...ect)
How do i correct it?
Would putting the amps through a power conditioner help?
Click to expand...

Probably not; the RF is probably not coming through your house wiring. It's probably due to faulty shielding in your guitar, one/some of your cables, or your amp.
 
It's not bad shielding, actually nothing is wrong with your gear, it happens with top of the line stuff too. Your guitar is basically a giant antena so if it's pluged into a speaker, you pretty much have a home made radio. If you're close enough to a transmitter you're going to pick it up, I sat in on a studio session in a well built studio using pro gear and it still happened.
 
Its always the same old timey station, probably AM, with constant ads for branson, missouri.

i have nice planet waves cables, but then i have cheap ones on my floorboard, would getting better cables help? my signal is noiser than i would like, either way. So if i get a new power supply, new floor board cables, and put more shielding in my gutiars, would i eliminate it?
 
ScreamingHead69 said:
It's not bad shielding, actually nothing is wrong with your gear, it happens with top of the line stuff too. Your guitar is basically a giant antena so if it's pluged into a speaker, you pretty much have a home made radio. If you're close enough to a transmitter you're going to pick it up, I sat in on a studio session in a well built studio using pro gear and it still happened.
Click to expand...

But it could be. I had a bad shield on a guitar input a few months ago that did they very thing he is talking about. I fixed it and it the radio station bleed went away. That's not to say that it can't happen even when everything is shielded up tight, but a bad shield can make it happen where it wouldn't otherwise be a prob.
 
fretwire3d said:
Its always the same old timey station, probably AM, with constant ads for branson, missouri.

i have nice planet waves cables, but then i have cheap ones on my floorboard, would getting better cables help? my signal is noiser than i would like, either way. So if i get a new power supply, new floor board cables, and put more shielding in my gutiars, would i eliminate it?
Click to expand...

Unfortunately, the answer to your question is "who knows?" It's probably not coming over the power lines, though. Is this something you've always had, or is it a new development? If it's new, what else changed at about the same time it started? That might give you a clue as to what to look for. Ferreting out noise probs can be a frustrating task.
 
the same thing happens every time my band practices...... we usually have our pretty little death metal songs inturrupted be sermons... >.<
 
BlackHawk2029 said:
the same thing happens every time my band practices...... we usually have our pretty little death metal songs inturrupted be sermons... >.<
Click to expand...

Ah, a conspiracy. I hope you are all wearing your tin foil hats... ;^)

Where does the radio noise come from? Your guitar amp, did you say? If you fire up your amp with everything else powered down, do you hear it? Are you running any cables from your amp to the PA? If you plug straight into the amp do you hear it? If not, add your stompboxes to your signal chain one at a time; is there one box in particular that is the culprit? It could be something as simple as a loose nut on an input jack.

My advice is to do some extensive troubleshooting to find out if there is a particular cable, box, guitar, etc. that brings in the noise before you go throwing money at the prob and hoping you'll solve it. There's no telling where the gremlin could be. I chased a 60 Hz hum for hours once, and it turned out to be a ground loop caused by the lack of insulating washers on the screws that hold my EQ onto the metal rails on my FX rack. That took some detective work.
 
BlackHawk2029 said:
the same thing happens every time my band practices...... we usually have our pretty little death metal songs inturrupted be sermons... >.<
Click to expand...


it's divine intervention! :eek:
 
fretwire3d said:
Its always the same old timey station, probably AM, with constant ads for branson, missouri.QUOTE]
Actually AM signals reach further then FM signals and bounce more, in which case a shit ton of wiring in your house would probabaly target everything straight at your rig.
Click to expand...
 
I'm guessing this'd be more of a problem in bigger cities, with more radio stations competing for that bigger market? When I used to live in Indianapolis, I'd pick up a radio station through my Vox T25 bass combo. Been living in Connersville, IN again, for the past 6 years, and haven't even picked up the local AM or FM station.

Matt
 
Some already valid thoughts;

Wires/cables are antennas nothing you can do to stop that but you can do a few things to help minimize the effect. Excessively long cables tune to lower frequencies in the A.M. band, big coils make it worse. The idea is to detune your gear to be less receptive. You can try those snap-on ferrite chokes to help keep some of the signal level down before it enters your gear but I've only seen this to be marginally successful. Sometimes simply moving one piece of gear a little this way or that will upset the signal orientation and minimize the effect. You've probably already noticed that it seems to get worse at night. That's because the stations typically are allowed to reorient their antenna patterns.

It could be your gear...some gear simply isn't designed as well as others when it comes to RFI rejection. This could get extreme but if you've got a strong electronics background, you could break out the o-scope and start chasing the A.M. signal to the point where it's being rectified. Sometimes the signal is hitting a single circuit with a PN (transistors and diodes) type junction and bammo...instant A.M. detector. Installing a bypass capacitor across that junction could be the fix.

Could be the utility source. I'd have a long hard look at the outlets, the utility panel and the grounds. In some areas, it's permissible to use the conduit as the ground path and not requiring a dedicated ground conductor. Conduit connections aren't as good as a contiguous piece of cable. The joints are sometimes loose and can be less than optimal. Also in some cases, even if there is a ground wire, it could be daisy chained through each of the outlets on the way back to the utility panel. If one of the cross-connects is open, no ground...and, again, open ended (and yes shorted wire...I'm not gonna get into an RF propogation and coupling discussion) can act as an antenna. For this, you really should hire a professional to test/check/verify. NEVER, add a ground to your studio! The ground source should come from a single point located at the utility panel. This is an area for an experienced electrician.

Bottom line, clean up the cables, try to get everything plugged into the same utility source with a known common ground point (if you've lopped off the 3rd prong of the power cords...shame on you). After that, unless you've got some RF and electronics background, you're shooting in the dark. A.M. + anything amplifier = pain in the butt.

Good luck
 
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