Help needed to solve why speakers click when the electric heater goes on

[Jon Bridges]

Can anyone tell me why they think the electric ignition from a heater being turned on could cause a click in nearby speakers, and even better how it can be prevented. They are about a meter apart and the speakers are on stands resting on a polyester carpet. It happens on speakers in 2 separate rooms with the nearby heaters.

Any thoughts gratefully received.

Thanks
Jon

 

[ashrow]

i had a issue with a stat on a fire(back boiler) causing the same with the TV's in a whole house, replaced the stat and all was ok
When you say a ignition on a heater can you be more specific, ie what type or heater etc etc please

 

[ackbarthestar]

Radio frequency sparking (interference) caused by poor EMC at the switch. A small, radio frequency suppression 100pf - 100nF capacitor (must be 350-500V) across the terminals of the heater switch should kill it.

Although I'm amazed that this preventive method wasn't already included by the heater manufacturer.

 

[telectrix]

get the same thing with fish tank light switching on/off causes computer speakers to click. ( about 3ft. away )

 

[Jon Bridges]

It was just something a customer asked me and I didnt really have any answer. The heaters are gas fired convector heaters, about 25 years old.

 

[Edd]

as above this is an EMF caused when any switch is operated,,, great fun to get a file and run a 9 v battery down it, most radios will start clicking, its a wide band transmitter,,, add a cap and inductor the you have a transmitter

 

[Jon Bridges]

However you get your kicks Edd ;-)

 

[ackbarthestar]

Yes, every file should have a tuned circuit attached.... There must be something the Chinese could come up with and sell in a pound shop !

 

[Darkwood]

When you say electric ignition are they mains powered, battery or piezo crystal ignitions..... are your speaker wires run close to power cables, are your speakers cheap...all these will have a bearing on how the speakers are picking up the RFI or induced EMF problems and come with their own solutions but as already mentioned a suppressor may be a good starting point but its possible the spark itself is been picked up as it gives of an electro - magnetic pulse through the air.

 

[telectrix]

"something in the air" -- thunderclap newman , 1969.

 

[Marvo]

Try replacing you speaker wires with CAT5 cable. Ground the sheath to the chassis of the Hi Fi and it should prevent RF interference. It's cheap and it's also got surprisingly good frequency handling, depending on the power of the speakers you can double-up, triple-up or even use four of the wires together as a single conductor.

 

[grantr37]

25 years old, have they been checked out by a Gas installer to make sure the burners are ok and the hoses etc are not leaking?.......the click on the speakers is being picked up by the circuit of the stereo/TV/Computer and a supressor at the switch/contact should help to cancel that out..,,,if its the ignitor itself, where the spark jumps the gap, then this can't be cancelled out and will always be there..not too sure if a Gas convector is still a safe bet these days, probably don't make them anymore do they?

 

[Darkwood]

You could always bye a thick jumper, this will have the benefit of saving on gas bills too and interference free easy listening .....
BTW i give these helpful tips absolutely free

 

[ackbarthestar]

"something in the air" -- thunderclap newman , 1969.

Nothing like being old is there? ..........

 

[ackbarthestar]

Try replacing you speaker wires with CAT5 cable. Ground the sheath to the chassis of the Hi Fi and it should prevent RF interference. It's cheap and it's also got surprisingly good frequency handling, depending on the power of the speakers you can double-up, triple-up or even use four of the wires together as a single conductor.

It doesn't help in most situations, better to use a good quality pre-amp with FET inputs that will provide a good common mode rejection ratio and allow the CAT5/6 to carry the common signal.