144 MHz 0.36W ARDF transmitter

The desire to assemble a powerful transmitter arose from the fact that training with low-powered TX results in mistakes during the actual competition, because of a wrong feeling of the distance to the transmitter. Therefore, the well-known timer by Bodo DL4CU was extended by a rather powerful transmitter, having almost the power of the competition one. On the other hand, the circuit is rather simple, uses wide-spread components and can be tuned using a 2 m RIG with a good working S-meter. The transmitter can use a wide-spread quartz resonator of 20,734 MHz. The printed circuit board, together with the quartz and 2N4427, is available on Ebay from radioqwerty1.

Have fun!

Schematics

The size of the board is 155x31 mm:


Board

Photo of the assembled transmitter board (slightly corrected since that ;):

Board
Board
Board