Single coil pickups interfering with a CRT Television?

Red Sleeping Beauty

I haven't played my Strat in a good while and I plugged it in there last night after changing the strings. Usually I play with the TV on in the background and the telly's a few years old so it's been grand. But then last night after playing (I was only playing for about a half hour at low volume) the TV's picture started to warp and bend and "wobble/ripple".

Has anyone ever noticed this or heard of it before ?
Strangely enough when I turned it back on there this morning it was rippling a bit but now it seems to have stopped

It's a standard Mexican strat, a few years old with a Dimarzio Hot Rail in the bridge.

I really wasn't playing for that long or for that loud but I May have knelt down next to the telly a few times with it. Bloody strong pickups eh ?

Dord

It's usually the other way around... :pac:

The TV is putting out RF Interferance which is picked up by singlecoil pickups. Turn it off and you should notice the noiselevels drop. It's the same with lightbulbs, if I position myself a certain way in my room while playing guitar the hum goes down. I could just turn it off and play in the dark but thats not too good.

Red Sleeping Beauty

Ah yeah definitely , I always notice any electrical appliance gives me loads of hum. The hot rail is of course ok and the hum is less in the 2,4 position what with them being out of phase (I think?).

Dord

Alan Rouge wrote: »

Ah yeah definitely , I always notice any electrical appliance gives me loads of hum. The hot rail is of course ok and the hum is less in the 2,4 position what with them being out of phase (I think?).

In position 2 and 4 the pickups are working in series together and "buck the hum".

Red Sleeping Beauty

Cheers, I wasn't on top of the telly but I'm in a box room so I would've knelt down or stood in front of it...

Interesting that the humbuckers (which are in my other guitars) didn't do anything...

Ross Mc

em thats cause they are humbuckers

Red Sleeping Beauty

Oh,
I was working off of the assumption that this happened cause the pickup is a magnet and magnets break tellys

Ross Mc

Alan Rouge wrote: »

Oh,
I was working off of the assumption that this happened cause the pickup is a magnet and magnets break tellys

humbuckers are made so they aren't as load as single coils, it's the same putting your single coils into position 2 or 4

L.R. Weizel

I get a lot of hum from my laptop, which is annoying because of how I record. That said as much as people complain about it, if you use a noise gate on the recording nobody's going to notice the noise mixed in that much, especially when distorted(which is when you hear most of the noise anyway).

Red Sleeping Beauty

Yep I get laptop hum as well but hopefully the magnets can't harm the aul laptop.

Just about anything can set off single coils from what I can guess. I suppose wax potting them and making sure the inside of the guitar is shielded would help...

Paolo_M

Humbuckers actually work by amplifying the difference between the signals on each coil. Because electrical noise and interference is coupled equally to both coils the sum of the different signals = 0, and 0 noise output.
The signal is coupled opposite but equal in each coil and therefore get's amplified and puts out more signal (usually) than a single coil.

Poisitions 2 and 4 on a strat work in a similar fashion though not quite as well because they are further apart and the noise may not coupled exactly equally to both.

As an example; say you're playing next a lamp and picking up noise. A humbucker might pick up 15mV of noise. Because of the humbucker design this will be coupled pretty much exactly to both coils. The noise output will be the sum of the difference, 15mV + (-15mV) = 0mV.
The 2 and 4 poisiton might go 15mV + (-12mV) = 3mV. This is 'cos one pick up is bound to be a bit further from the noise source.
Normal single coils just picks up the 15mV noise and sends it along with the signal.

Hope that makes sense.


Alan, I doubt very much that your pick ups were interfering with the telly. The magnetic field from a pick up isn't that strong, nor is any electro static field they might create.
Did you have your amp on? What kind? Are you using an aeriel or piped TV?
The only thing I can think of is RF interference from your amps power supply or maybe positive feedback from your single coils picking up TV noise, amplifying it and messing again with the TV, but I dunno...
Properly shielding the guitar will make a big difference.

Red Sleeping Beauty

The amp was on, it's a 100Watt Marshall Valvestate and it's at the other side of the room (the box room that is, so telly's in one corner/amp in the other). I think at the time I had on the normal piped telly but I've got that going into a video machine which is conntected to the TV via scart.

L.R. Weizel

Paolo_M wrote: »

Humbuckers actually work by amplifying the difference between the signals on each coil. Because electrical noise and interference is coupled equally to both coils the sum of the different signals = 0, and 0 noise output.
The signal is coupled opposite but equal in each coil and therefore get's amplified and puts out more signal (usually) than a single coil.

Poisitions 2 and 4 on a strat work in a similar fashion though not quite as well because they are further apart and the noise may not coupled exactly equally to both.

As an example; say you're playing next a lamp and picking up noise. A humbucker might pick up 15mV of noise. Because of the humbucker design this will be coupled pretty much exactly to both coils. The noise output will be the sum of the difference, 15mV + (-15mV) = 0mV.
The 2 and 4 poisiton might go 15mV + (-12mV) = 3mV. This is 'cos one pick up is bound to be a bit further from the noise source.
Normal single coils just picks up the 15mV noise and sends it along with the signal.

Hope that makes sense.


Alan, I doubt very much that your pick ups were interfering with the telly. The magnetic field from a pick up isn't that strong, nor is any electro static field they might create.
Did you have your amp on? What kind? Are you using an aeriel or piped TV?
The only thing I can think of is RF interference from your amps power supply or maybe positive feedback from your single coils picking up TV noise, amplifying it and messing again with the TV, but I dunno...
Properly shielding the guitar will make a big difference.

Yeah, especially since most pickups are passive electromagnets they're not going to do all that much.

I know Fuzz pedals can pick up radio stations though...