reconrider8
Member
i know this can go very deep but how does a ham radio transmit? from the time you push the ptt to the time the other person hears your voice what happens in the radio? im not asking about repeater operation but inside the radio.
In 20 words or less? LOL I suppose, these days you can probably get everything on one IC chip, but here's a simple diagram. Basically, you need a circuit to generate the proper RF signal, and you modulate it with your audio. Then there's filtering too.
It's always blown my mind how someone just sat down one day and thought "well if I combine all these pieces I can get it to do this". I understand building smaller circuits but even then I scratch my head sometimes. It just amazes me what goes into building a radio or even a computer from the ground up. People knock the cheap Chinese radios but even their engineers know more than I could ever dream of about making something work haha. I suppose if you go back to the early days it may be easier to understand but even then there's a lot to wrap your mind around.
In super oversimple half-assed terms for FM modulation:
1) The vibrations in the microphone turn into a modulated electrical signal going into the Frequency Generation Unit.
FGU is two parts: frequency synthesizer and signal oscillator/mixer.
2) Reference oscillator in frequency synthesizer oscillates its own generated signal at a constant rate (say, for instance, 869.8875 MHz). A variation is applied to this reference frequency to generate the RF frequency on which the radio itself transmits (say, for instance, 870.2125 MHz). This signal is passed to the signal oscillator.
3) The signal oscillator superimposes a filtered version of the audio modulation signal on to the signal coming from the frequency synthesizer. This produces a modulation in the RF frequency, and the composite signal is then passed to the PA.
4) The power amplifier ramps up the signal strength of the composite (modulated) RF signal and passes this signal to the antenna.
5) The antenna resonates with this oscillating signal, causing energy to dissipate out from the antenna with relatively high efficency.
6) Receiving radios essentially do the same process in reverse - receiving, demodulating, and filtering to output audio.
It's always blown my mind how someone just sat down one day and thought "well if I combine all these pieces I can get it to do this".
Perfect
It's always blown my mind how someone just sat down one day and thought "well if I combine all these pieces I can get it to do this". ....
How does someone come up with the idea that radio waves can bounce off.. I guess I'm just to stupid to figure out stuff
How does someone come up with the idea that radio waves can bounce off.. I guess I'm just to stupid to figure out stuff