Why TV Reception Does Not Get Disturb With Thundering

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saeedakhan

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Dear Forum Members,

Why TV Reception Does Not Get Disturb With Thundering?

Saeed A Khan
 

If the signal ia sppressed carrier AM modulated IT is affected by lightnings ( some white and black dots or lines ). If the mains is absent for some time the most evident signal is the screen all black.
If it is a digital transmission, being phase modulated and with some error correction alghortims, the worst effect is the freezing of the image for 1/10 sec or so.

Mandi
 

Old analog television broadcast is vestigal sideband AM. The modulation polarity is inverted, so impulse noise tends to cause dark speckles instead of bright speckles. That hides the noise pretty well.
 

There is also the frequency content of the radiation. It is a pulse with relatively slow rise and fall times and long pulse width. This puts the majority of the energy below 1 MHz.

This is the reason for the tropical AM broadcast band in some parts of the world. At 3 MHz or so the lightning energy is much lower.
 

perhaps thundering's spectrum is not following into

the spectrum of tv.


best regards





saeedakhan said:
Dear Forum Members,

Why TV Reception Does Not Get Disturb With Thundering?

Saeed A Khan
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