# Frequency-to-Amplitude and visa-versa conversion -- possible?

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Hi:

Please don’t get upset at me.

I apologize profusely for posting something similar in a different thread. However, you will notice some difference as you read.

Does a device that switches frequency [in number of Hz] with peak-to-peak amplitude [in watts-per-meter] equivalent to the Hz number of 1-Hz-photon(s)-per-second-per-meter – and visa versa -- exist? If not, is it possible to construct one?

In this device, the input of a signal that has a frequency of X Hz and a peak-to-peak amplitude of watts-per-meter equivalent to Y number of 1-Hz-photon-per-second-per-meter will result in the output of a signal that has a frequency of Y Hz and a peak-to-peak amplitude of watts-per-meter equivalent to X number of 1-Hz-photon-per-second-per-meter.

NOTE: The electronic signal’s amplitude itself is never measured in photon-per-second-per-meter. It is measured in watts-per-meter. It’s just that the watts-per-meter is equivalent to that of the given number of 1-Hz-photon-per-second-per-meter. An electronic signal is made of electrons, not photons.

Given a constant wavelength/frequency of a signal of EM radiation [1 Hz in this case], a greater number of photon-per-second-per-meter is equivalent to more watts-per-meter.

However, it’s important to remember that the quantum unit of an electronic signal is the electron, not the photon.

Thanks,

Green Xenon

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I don't really understand what you're asking for.

Monochromatic light beams have two types of energies associated with them. The energy of individual photons, which is related to the frequency. And the energy of the beam, which is the sum of all the photons in the beam.

Now, you seem to be asking if you can have a device where you put in a beam of a certain frequency and get out one of another. This is actually possible and done very often in labs.

The processes use things called non-linear crystals, the most common in use that I'm aware of is frequency doublelling, in my lab all of the laser systems run at 800nm and we can frequency double any of them up to 400nm using a non-linear crystal.

There are also more complicated systems which use very similar physics such as optical rectification, this is often used for building THz spectrometers.

Where you put in optical light, and get out light at ~1THz. Which very far IR.

There are other devices like photonconducutive dipole antennas...

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Frequency to voltage converters are quite cheap, and you should also look up VCO.

you make take Voltage level as being your amplitude and convert it to what ever output accordingly.

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I don't really understand what you're asking for.

Monochromatic light beams have two types of energies associated with them. The energy of individual photons, which is related to the frequency. And the energy of the beam, which is the sum of all the photons in the beam.

Now, you seem to be asking if you can have a device where you put in a beam of a certain frequency and get out one of another. This is actually possible and done very often in labs.

The processes use things called non-linear crystals, the most common in use that I'm aware of is frequency doublelling, in my lab all of the laser systems run at 800nm and we can frequency double any of them up to 400nm using a non-linear crystal.

There are also more complicated systems which use very similar physics such as optical rectification, this is often used for building THz spectrometers.

Where you put in optical light, and get out light at ~1THz. Which very far IR.

There are other devices like photonconducutive dipole antennas...

You're talking of photonic/optical systems. The freq-to-amp-amp-to-freq converter I'm discussing is purely-electronic and not photonic/optical at all.

Sorry for the confusion.

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have a look at the LM2907 and 2917, as for VCOs I like to use the 4046, but there are 100`s of other methods from UJTs to chips or even thermionic valves.

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Frequency to voltage converters are quite cheap, and you should also look up VCO.

you make take Voltage level as being your amplitude and convert it to what ever output accordingly.

There are several applications I can think of for the aforementioned device:

1. Transmitting/recording too high a frequency signal on a medium that does not have the bandwidth required to handle the high-frequency

2. Transmitting/recording too large and amplitude signal on a medium that does not have the dynamic range required to handle the large amplitude

3. Generating a higher-frequency signal from a bunch of lower-frequency signals

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all of which are used in radio applications and some of the old Music Synthesizers too

although where a freq is too high and needs to be resolved to something lower, dividers or hetrodyne are commonly used, in radio the IF and mixer does that too.

but sure, when you have either converted to a simple voltage, you can use that ramp up or down any output you like.