Electronic schematics, circuit designs
Rf 15W - 30W power amplifier KT922, KT930, KT934
This amplifier ensure the power you need for a small transmitter.
Depending of input power, power supply and transistor, this amplifier can boost from 15W up to 30W.
The most important components : 7805, 1N4001 diodes mounted in series, 120 ohm / 2W resistor and 1N4145 diodes.
The setup : trim P (220 ohm ) untill you obtain 50mA thru T1 and 100mA thru T2. Without any input signal you must measure 1.5V like in the schematic, if the voltage is higher the 2 transistors can burn.
At 12V and 0.1W input rf power the output is 6W and with 0.5W the output is 15W.
At 24V and 0.1W input power the output is 10W and with 0.5W the output is 25W.
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Rf 150W BlX15 power amplifier
Rf 150W Blx15 power amplifier, enough to cover 50Km with one folded dipole.
You must use one heatsink about 20 cm wide, 5 cm height and minimum one cooler.
Components:
* L1 = 2 turns / 9mm / 1mm
* L2 = L5 = rf choke 1mH
* L3 = 3 turns / 9mm / 1.5mm
* L4 = wide - 7mm / length - 40mm
* L6 = 3 turns / 7mm / 1.5mm
* L7 = 4 turns / 7mm / 1.5mm
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88 108 MHz 40W wideband power amplifier MRF171A
One wideband fm power amplifier designed with MRF 171A MosFet transistor. The output rf power is somewhere around 40W , the gains is 20dB ( 100 X ) . The input rf power is 400mW.
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