There are three approximate frequency bands being discussed. The bands are separated by a factor of about 1 million. The width of each band is a factor of 3-8.
Human voice audio - 500 Hz to 4 kHz (the modulating signal)
VHF-UHF radio - 330 MHz and 1320 MHz
"Light" - 300 to 800 THz
This is an arbitrary restriction to the visible. (Note that the first person to mention the word "visible" was you!)
The original comment (ClikeX) clearly included radio waves in their intent, and that is an accepted definition! It's the definition I see used in practice as an optical engineer.
ClikeX originally claimed that the USSR had lasers in 1945 (untrue) and that Leon Theremin invented the detection of sound vibrations or audio reproduction of via light (also untrue).
The confusion here is between the two different eavesdropping systems developed by Theremin: The Buran eavesdropping system (which used likely-near infrared on windowpanes) and "The Thing" (which used VHF-UHF radio on a custom device).
Your repeated insistence on the unrelated point that "light" and "radio" are technically both electromagnetic waves isn't clarifying anything.
I'm quite confident it was an optical wavelength! ;)
> ClikeX originally claimed that the USSR had lasers in 1945 (untrue) and that Leon Theremin invented the detection of sound vibrations or audio reproduction of via light (also untrue).
> The confusion here is between the two different eavesdropping systems developed by Theremin: The Buran eavesdropping system (which used likely-near infrared on windowpanes) and "The Thing" (which used VHF-UHF radio on a custom device).
Great summary!
> Your repeated insistence on the unrelated point that "light" and "radio" are technically both electromagnetic waves isn't clarifying anything.
I hope it's helped clarify that of the terms used here (light, radio, and electromagnetic waves) only "radio" is clearly distinct as "light" and "electromagnetic waves" are often synonyms.
> Yes, he invented the technique of monitoring audio through light. How was I wrong there?
> These radio waves have a wavelength of about a meter, which is about 6 orders of magnitude longer than an optical wavelength.
> The point was light being used for audio, not specifically laser as a light source.
> You seem to keep responding to multiple people defend your point, but he used 1320 MHz in the thing which is not light.
These comments disagree on important definitions. I don't think it's pedantic to point this out.