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Interruption while using telephones and Mobile

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Junior Member level 1
Jun 3, 2005
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When speaking in telephone and at the same while my mobile receives any message or call, there is a disturbance in the telephone.

What causes this interruption and is there any chance for eliminating this noise...

Arun Nandha Kumar

This efect is very normal in GSM. GSM transmit burst of RF at 400 Hz (aprox), peak of 1W or more, those burst are abruts, and the speaker coil can receive the envelope and generate low frecuencies (400 Hz)

You will cannot eliminate it. Only separate the cellular from the hook of phone.

Do you think about, what will happens in your head when you are talking by cellular?, your ear is touching the cellular phone........

You hav to go inside your phone and find where interference signals comes into the telephone. When those found : put chokes and about 100 pf capacitors (bigger val;lues do not help due to high self inductance) in worst case shielding to the affected circuits to suppress the noise . but it could be the case that you wont able to eliminate it at all.

If only it were that easy to shiled our brains <G>

i would like to add up with arunnandhakumar's question
when i use the cell phone near a monitor, the screen scrambles for few seconds.

will the screen lose any of its property on continuous exposure?

and will the tft (lcd) screen will also get affected in any way.

If the equipment survives after you remove the cell phone, there is a very little chance to observe side effects, or property changes. However, if you keep the cell phone near the area where the main power supply or other power circuits are installed, you may blow them, especially if they are not shielded (mostly in new monitors). The effect on other low power circuits is only temporary, it may disrupt their functionality, but after a reset or power cycle, everything should be fine.


Interruption is caused because of the electromagetic sigal ( eg. incoming call) being received bya mobile to the electrons generated in the Electron tube of a Television set.

I have another questions which has the same effect, but I can't explain it in a good way, why when I open my PC's case or any metallic part and touch it with my hand or with a screw driver I hear this low noise sound?
Try it... :)

This could be because of an electrostatic current which flows over the surface of conductors.

See, there it is again.....that nasty EMI.

Have you tried aluminum foil?

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