With this simple amplitude modulated transmitter for long waves, you can broadcast your transmissions over a short distance.The hurdy-gurdy operates at a frequency of approximately 160-180 kHz, which falls into the range of long waves.The power of the transmitter is small, and therefore no permits are required to use it.
The transmitter is made on a single transistor 2sk30A.Powered by two 3.7-volt batteries.
The coils are wound on paper frames into which a ferrite rod is inserted.I used a rod from radios with a length of 8 cm and a diameter of 8 mm.The coil L1 contains 60 turns of wire with a diameter of 0.14 mm, and the connecting coil L2 also contains 20 turns of wire.The closer the coils are located to each other, the more powerful the signal from the transmitter will be.When setting up, if the generator does not start, swap the L2 coil
The photo shows an oscillogram from the output of the transmitter without a load, without an antenna.The signal is an excellent sine wave with an amplitude of 7.5 Volts.The sound signal to the input of the transmitter was supplied from the player.The range of such a transmitter without an antenna is within a radius of one apartment.
