🚀 go-pugleaf

In article <etxansk.715946468@garbod20> etxansk@garbo.ericsson.se writes:
>
> I'm wondering where the snowy screen information comes from, on a TV
>set that isn't receiving any real RF video signal.
>
> Is the snow "in the air" or does it only exist in the TV's tuner?
>

Most of it is generated by the active devices in the front-end amplifier
of the tuner (shot-noise, thermal noise etc..), some is just the accumulated
background noise from all the man made sources (finite probability that
a photon from even the weakest transmitter will reach your set), and a
few percent is the remnents of the big-bang. (4K background radiation)
(probably many other natural sources as well).

If you disconnect your antenna, you'll see the difference between the
internally generated noise and the background (usually not much difference).



-- 
Michael Katzmann	  >	Broadcast Sports Technology Inc.
~~~~~~~~~~~~~~~~	 <	Crofton, Maryland. U.S.A
Amateur Radio Stations:   >
NV3Z / VK2BEA / G4NYV	 <	opel!vk2bea!michael@uunet.uu.net