posted on Nov, 15 2012 @ 11:52 PM
The first stage amplifying transistor in most audio amps will act like a detector stage when it is presented with modulated RF. The transistor’s
maximum operating frequency is high enough to be reactive to those frequencies, but the circuit’s cutoff is just above the audio frequency range. So
the audio gets feed through from the RF signal coming in, while the RF gets dumped, and you hear the audio in the output of the amplifier.
The poor quality audio cables that come with most computer speakers are quite ineffective at keeping RF out.
If you are close to a major interstate, or truck stop, you will often hear truckers bleeding through the audio amplifier equipment. You will hear
anything from people talking, to playing sound effects, and music. You know, the normal junk that goes on, on CB.
If you live near a ham operator, costal maritime station, short wave broadcaster, or am station, you may hear audio bleeding through. If it is a ham
operator, or costal station, the audio will be extremely garbled, if not outright unintelligible.