Hints
Often you suffer from PC power supply interference.The simplest way to eliminate it is showm below
the filter circuit diagramm
L1 and L2 consist of 25 turns of 1,2 mm wire on 25 mm diameter u50 ferrite ring cores,L3 and L4 - 5 turns bifilar well insolated(above 350 V) wound on 25 mm diameter u600 common core.C2 has been designed for 400 V,the other capacitors - no less than 1000 V.The filter is connected to PC by short cable passing through u600 ferrite core to X1-X3 side
An another useful circuit.Cheap power amplifier for HF below 20 m.
the PA circuit
diagramm
I used one of the cheapest HEX FET IRF540.There is nothing special in this
PA.Input power about 100-200 mW is enough to get 15-30 W output(depend on a
band) and 6-9 A DC.On TX mode gate circuits are switched to 5 V. T1 uses
bn-43-202 multi-aperture core and consists of 3X5 turns,T2 - bn-43-3312 core,
primary winding is 4.5 mm copper tube,the secondary one consists of 5 turns. By
R3 you should get VT1 DC about 300-350 mA and by R9 for VT2-VT3 - about 70 mA.
The board has to be installed on a large surface heatsink(fan is the better
choice) The linearity wasn't tested,but it's enough for CW and even for PSK.
2 el. switching 15 m Delta Loop
layout of the antenna
You can find here switching pattern active loop feeding Delta Loop.Every triangle side length is 4.9 m,the distance between triangle bases is 3.6 m.The gain is 8.5 dBd,forward/backward ratio is better than 12 dB,forward/sideward one is better than 16 dB.1,6 m(1/6 wave length) length RG58 60 degrees phasing line is connected to A point from one side and to B point from another one.Switching by relays a feedline between A and B points accomplishes pattern reverse.If you're using 75 Ohm feedline it has to be connected through quarter wavelength 50 Ohm cable transformer(e.g.RG58)
MMANA antenna file
the PA circuit diagramm
I used one of the cheapest HEX FET IRF540.There is nothing special in this
PA.Input power about 100-200 mW is enough to get 15-30 W output(depend on a
band) and 6-9 A DC.On TX mode gate circuits are switched to 5 V. T1 uses
bn-43-202 multi-aperture core and consists of 3X5 turns,T2 - bn-43-3312 core,
primary winding is 4.5 mm copper tube,the secondary one consists of 5 turns. By
R3 you should get VT1 DC about 300-350 mA and by R9 for VT2-VT3 - about 70 mA.
The board has to be installed on a large surface heatsink(fan is the better
choice) The linearity wasn't tested,but it's enough for CW and even for PSK.
2 el. switching 15 m Delta Loop
layout of the antenna
You can find here switching pattern active loop feeding Delta Loop.Every triangle side length is 4.9 m,the distance between triangle bases is 3.6 m.The gain is 8.5 dBd,forward/backward ratio is better than 12 dB,forward/sideward one is better than 16 dB.1,6 m(1/6 wave length) length RG58 60 degrees phasing line is connected to A point from one side and to B point from another one.Switching by relays a feedline between A and B points accomplishes pattern reverse.If you're using 75 Ohm feedline it has to be connected through quarter wavelength 50 Ohm cable transformer(e.g.RG58)
MMANA antenna file
2 el. switching 15 m Delta Loop
layout of the antenna
You can find here switching pattern active loop feeding Delta Loop.Every triangle side length is 4.9 m,the distance between triangle bases is 3.6 m.The gain is 8.5 dBd,forward/backward ratio is better than 12 dB,forward/sideward one is better than 16 dB.1,6 m(1/6 wave length) length RG58 60 degrees phasing line is connected to A point from one side and to B point from another one.Switching by relays a feedline between A and B points accomplishes pattern reverse.If you're using 75 Ohm feedline it has to be connected through quarter wavelength 50 Ohm cable transformer(e.g.RG58)
MMANA antenna file
layout of the antenna
You can find here switching pattern active loop feeding Delta Loop.Every triangle side length is 4.9 m,the distance between triangle bases is 3.6 m.The gain is 8.5 dBd,forward/backward ratio is better than 12 dB,forward/sideward one is better than 16 dB.1,6 m(1/6 wave length) length RG58 60 degrees phasing line is connected to A point from one side and to B point from another one.Switching by relays a feedline between A and B points accomplishes pattern reverse.If you're using 75 Ohm feedline it has to be connected through quarter wavelength 50 Ohm cable transformer(e.g.RG58)
MMANA antenna file