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HF End Fed Half Wave


The EFHW monoband matching unit allows for a half wavelength of wire tobe connected, giving a 50 Ohm impedance
post 16 Jun 2024
HF End Fed Half Wave

Antenna End Fed Links

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EFHWA tuner
Un tipo un balun 1:7 oppure 1:8 per fronteggiare gli ohm presenti ai vertici della nostra antenna, quindi 3 giri di avvolgimento primario e 21 o 22 di secondario andranno bene. per quanto riguarda il ROS non salgo mai sopra 1.6-1.8

Endfed per 17-20-30-40 metri
Una veloce multibanda E.F.W.H.A. dedicata ai piccoli quadri banda come il mio FT857D

End fed 1/2 wave matching system end feed
End-fed antennas are increasingly popular again, at least partly because of compact iron toroid cores. Small soft-iron cores allow compact, easy-to-build, low-power transformers and networks

End fed antenna lambda/2
Un trasformatore 1:64 su cui e' collegato un filo lungo lambda/2 della frequenza prescelta. una versione a 3 o 5 bande in modo da avere maggiori chance su piu' frequenze. Un filo di rame teso ha un'impedenza superiore ai 3.3 K ohm e quindi per poter adattare l'impedenza ai 50 ohm della radio, con un toroide FT240-43 - 1:64

An EFHW antenna for 160-10m band
An efhw as inverted-l from the feedpoint at the edge of property, about 10m upwards into the direction roof ridge


23cm Yagi Antenna building

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

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

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