Thanks Rick, I understand what phase noise is. I work on phase locked
loops and look at the signals they produce with spectrum analyzers
almost daily. And I understand why transmitters that do not use phase
locked loops do not produce any, or at least very little "phase noise."
Whatever noise they do generate we would give a different name. I am
sure that transmitters using no phase locked loops are not perfect. They
will have some amount of noise due to ripple in their power supplies or
just plain thermal noise in oscillators and amplifiers. Boltzmann's
constant is a constant, so is not zero, T in every transmitter I have
worked on is at least 273 K, so the physics says there will be noise.
The noise may be small, but not zero. It would be interesting to have
some real measurements.
DE N6KB
Ken, the noise we are talking about is called "phase noise" and none of
these radios had any phase noise (by design).
73 - Rick, DJ0IP
(Nr. Frankfurt am Main)
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|