I am trying to create build a morse code transmitter. I know that morse code is sent at 500 KHZ so I set my 555 to spit out pulsating DC in a square wave with 9 volt peaks. But I am unsure wether antennas will transmit pulsating dc. And I also would like to add a couple filter capacitors on the circuit which block dc… but when I try to use a transformer to get ac from my pulsating dc it turns into a sine wave ac……. Any help????
How to turn pulsating DC (square wave) from a 555 IC timer into an ac square wave
555antennaradiotransformertransmitter
Best Answer
You should feed the antenna with a sine wave to transmit a pure single-frequency signal. A square wave as generated by the 555 will have many harmonics.
Morse code can be transmitted on any frequency. 500 KHz was, long ago, the marine morse code distress and calling channel.