Here it is a brand new TX300 FM transmitter. The
amplifier has exactly the same architecture as TX500 with the difference that TX300 has only one stage variable VHF amplifier.
It is a cute schematic that was made for all of you who wanted something even simpler than TX500 and with not as many necessary parts. It is a perfect circuit for
transmitting your music around the house and yard. Interesting feature is a gain control P1 that lets you adjust your desired output power and distance. If in case you want to replace Q2 with more powerful transmitter like 2n4427 or 2n3866 you will have to replace P1 with a resistor due to the higher necessary current. For much more info go to TX500′s page.
FM Transmitter 300mW Circuit
This power meter will let you test both the output power of Q2 (VHF amp) and Q1 (
oscillator). Circuit is now on the separate board so you can fit the main circuit of the smaller PC board.