> The aerial is connected to the grounded inductor. The coil has an internal parasitic capacitance which, along with the capacitance of the antenna forms a resonant circuit (tuned circuit) with the inductance of the coil, resonating at a specific resonant frequency. The coil has a high impedance at its resonant frequency, and passes radio signals from the antenna at that frequency along to the detector, while conducting signals at all other frequencies to ground. By varying the inductance with a sliding contact arm, a commercial crystal radio can be tuned to receive different frequencies. Most of these wartime sets did not have a sliding contact and were only built to receive one frequency, the frequency of the nearest broadcast station. The detector and earphones were connected in series across the coil, which applied the radio signal of the received radio station. The detector acted as a rectifier, allowing current to flow through it in only one direction. It rectified the oscillating radio carrier wave, extracting the audio modulation, which passed through the earphones. The earphones converted the audio signal to sound waves.
If you are building an AM crystal radio. [1] You will also need a high-impedance speaker [2] if you want to operate it without a power supply, otherwise you will need an amplifier. You can avoid using a commercial diode by making your own point contact diode as done in Foxhole radios [3] and you can make your own piezoelectric speaker from Rochelle salt [4]. Here [5] is one personal projects site touching all those topics.
In conclusion, you should be able to build a simple radio from copper wire, aluminium foil, a pencil, a razor blade, and baking powder.
AM peak detector is probably the easiest and primitive AM demodulator: it's basically made by a diode, a capacitor and a resistance. I implemented it when I was in the high school and I was making the first physics experiments.
The idea behind this demodulator is quite easy: the diode filters out all of the negative part of the signal, then the positive signal charge the capacitor and the energy is released in a quite constant way (R*C must be several order of magnitude higher than 1/f where f is the carrier frequency) during the negative signal "hole".
AI has created a new standard from which “average” is defined. Rather than a real life analog to a mathematic mean, it’s simply understood to be the level at which AI performs.
It is a tool, those who learn to use the tool will benefit more. average people will be average in using it, smart people have the potential to use it smartly.
2200 meter is LF (30-300kHz). Used mainly with huge coils and low power (1W EIRP). then there's VLF (3-30kHz). Then there's ULF (300Hz-3kHz) Then there's ELF (below 300 Hz), used by the stations in question. To put things into perspective.
Speaking of VLF, SAQ will broadcast on 17.2 kHz on July 2nd. You can pick it up with a soundcard directly (not using a DVB-T chip) depending on your location and use of antenna.
My understanding is that the MOS 6502 was MOS, so MOSFET. Not using MOSFETs would make it less of a replica.
Implementing the replica in an integrated circuit instead of discrete transistors would lower capacitance.
The delay time is a consequence of the capacitance.