144.000 Mhz CW Transmitter
Block Schematic of my homemade 144.000 MHz CW 1.5Watt transmitter
The Xtal osc is riped from an old AT-PC running 16MHz, it requeres 5.0 volt and use 18mA
those Xtal oscilators is accurate and needs no adjustment
The 5.0Volt 7805 regulator can also be ripped from the same old PC, then this transmitter, can be created for nomoney at all !
The CW-Keying is done by turning the PA-stage on or off with a P-channel fet or a PNP transistor
The PA transistor (2N4427) gets a bit hot, this can be solved by incerting a resistor in the collector/powersupply, to reduse output to about 800mWatt.
Here is one Buffer/Filter block, for 144Mhz: T2 is 5turns 0.6mm cu wire wound on a 5mm plastic form, see picture.
The output is one turn, the same circuit can also be used as a 16 to 48Mhz tribler:
then R1=notmounted, R2=4K7, R3=shorted. C1=47pf, C2=notmounted
T2 prim 16turns 0.2mm cu, sec 1turn
Transistor: almost eny fast small signal npn can be used, good luck
Here is a photo of my actual working version, dont place the coils to close.
