Long Distance Low Power Morse Code Transmission

287

03:29:29

The SPST switches are antennas. The oscillator on the left is a simple oscillator with very low gain to disturb the frequency of the oscillations as little as possible. The SPDT switch is for the user to switch to transmit morse (or other) code. On the left is an extremely high-Q band-pass filter. It accepts the transmitted signal but not the noise because it accepts a very narrow band of frequencies (noise becomes more and more the wider the band. In fact noise received is directly proportional to bandwidth) because of the high-Q. As a consequence of this it will change state between receiving a one or a zero very slowly compared to the radio wave period. This, however, shouldn’t be a problem if radio waves in the hundreds of thousands (or higher) of Hz are used and the transmissions are done by hand (few Hz max). This theoretically let’s morse code be transmitted across oceans and through thunderstorms by small battery powered tabletop transmitters if the right receiver is used. Also, the filters should be controlled not by inaccurate (by this thing’s standards) LC circuits, but by piezoelectric circuits, optimally in a temperature controlled environment for maximum precision.

published 7 years ago

hurz

7 years ago

Right, but on the receiver side its better to have a parallel resonator were you can store more and more energy into it till its much enough to detect it as signal. While a series resonator would resonate througth the antenna and will damped a lot, or in other words, it will not have the chance to accumulate the energy. A parallel resonator with a high Q (low resistance) as possible!

jason9

7 years ago

Yes, that makes sense. A very good idea. I’ll do that now.

hurz

7 years ago

But dont expect to go over the ocean with 1Watt the signal on receiver needs to be above the noise level, so some power is at transmitter needed 😜

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