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The versatile end-fed wire
A length of one quarter wavelength ie 20 metres on the 80 metre band is commonly suggested. Though such antennas do work, an extensive ground system or counterpoise is required for best performance
post 28 Mar 2024
Antenna End Fed Links →
End fed antenna lambda/2
drastically lower the impedance with a toroid FT240-43 on which we are going to wrap 14 + 2 coils of copper from 1mm
End fed 1/2 wave matching system end feed
Actual bandwith is more than 2 Mhz with VSWR better than 1:1,7 For 14 Mhz you need approx. 10 meters of wire, abt. 4,7m coax-cable 50Ohm or 300Ohm with a connector about 30cm from the shortend end
End-Fed Half-Wave Antenna & Tuner
The final device tunes a resistive load of 3-7 kilo-Ohms from 3.2 MHz to 12.6 MHz. 40 metres is covered and 30 metres too, but I lack a transceiver for it currently
HF End Fed Half Wave
The SWR is likely to be below 1:1.5 and when used as an omnidirectional vertical the low angle of radiation typically with a maximum at about 20 degrees will give good results on DX
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drastically lower the impedance with a toroid FT240-43 on which we are going to wrap 14 + 2 coils of copper from 1mm
Actual bandwith is more than 2 Mhz with VSWR better than 1:1,7 For 14 Mhz you need approx. 10 meters of wire, abt. 4,7m coax-cable 50Ohm or 300Ohm with a connector about 30cm from the shortend end
The final device tunes a resistive load of 3-7 kilo-Ohms from 3.2 MHz to 12.6 MHz. 40 metres is covered and 30 metres too, but I lack a transceiver for it currently
The SWR is likely to be below 1:1.5 and when used as an omnidirectional vertical the low angle of radiation typically with a maximum at about 20 degrees will give good results on DX
23cm Yagi Antenna building Finished antenna at 1275 MHz SWR under 1:1.5 at resonant frequency
50 MHz preamp Gain 26dB with the BFG135 Preamps for 144 and 430 MHz, for 50 MHz, the BFG135a is a cheap transistor and in my view rather strong. It is not easily damaged by static discharge or RF power. FG connection
30 Volt Computer Power Supply Stack A bonus was that i discovered that these did not need a standby load connected to the supply to keep them running just apply mains power and close the Start lead to ground