In article , Wim Lewis
wrote:

In article ,
duckman wrote:
Had a question for open discussion

Is there available, can it be done to have an AM and/ and or FM transmitter
that will broadcast over the entire AM and FM broadcast band at the same
time. Or at least multiple stations. E.G.

Do you want to broadcast a large number of different signals simultaneously
from the same transmitter, or many copies of the same signal?

Both should be pretty straightforward to do... if you want to broadcast
many copies of the same signal, you could just replace the LO with
a circuit that generates a number of carriers, superimposed. Each
frequency component in the LO will produce a corresponding copy of the
audio signal in the RF or IF output.

I don't know if it's possible to broadcast a single audio signal spread
over a wide band (instead of having one copy at each standard AM station
frequency, as above). My intuition says it should be possible to
amplitude-modulate some wideband noise, and any AM receiver with an
envelope detector would recover the signal. But mathematically, I'm not
so sure --- where would the sidebands go, how would the receiver
distinguish them from the overlapping "carrier"? Or could this be
thought of as a sort of self-despreading spread spectrum signal?
Perhaps I should just go to bed ...





If you just want to jam, build a 10.7 MHz transmitter and turn it on when
desired. Most cheap radios don't have good IF rejection and the signal
will capture the normally weak incoming signal from the broadcast.
However, the whole thing is illegal no matter what the method.

Steve