3V FM Transmitter 88MHz to 108MHz by BF982

Thursday, January 31st, 2008
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The important part of the circuit is formed of the Colpitts type oscillator. C3,C4,C5,C6,CD1-CD2 and L1 determines the frequency. BF982 and dual gate MOSFET are active parts in oscillator. When the input impedance of the MOSFET gate inputs are high, LC tank is not affected. However transistors force the LC tank and cause phase shift.
Two [...]

1.5W 1-2 km Range FM Transmitter by 2N2219

Thursday, January 31st, 2008
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This is a well designed basic FM transmitter that you can easily recive the signals transmitted from this transmitter in a 1-2km range with using a normal FM reciever. Another property of this circuit is that the bobin is placed on the printed circuit board. The input sound’s amplitude can be adjusted by using the [...]

15W Fm-transmitter

Tuesday, January 22nd, 2008
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It was five years ago when I did an attempt to build my first fm-transmitter. It ended in a giant faillure. The only thing it did was interferring with our tv-set. Looking back it was due to the lack of information I had. A schematic was my only help. Now, five years later, I know [...]