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Helix Antennas for HF Mobile
20 meter helix antenna. The antenna is approximately 65 turns of #14 AWG THHN stranded wire wound on a 1 1/2'' cpvc coil form
post 14 Mar 2024
Antenna CB 27 MHz Links →
Easy to build Deltaloop for 27.555MHz 11m, DL5DBM
In this setup you have a horizontal polarisation, the total length of the wire is 11,07 meters
Easy to build compact quad antenna
If you want to communicate with mobile units, with vertically polarized antennas then you must use vertival polariztion
Extended Double Zeppelin 27.500
Full wavelength: 300 / 27.555 = 10.887 x 0.94 = 10.234 m Top sections of antenna: 0.64 wavelength: 10.234 x 0.64 = 6.550 m for each leg
Hb9cw for 27 mhz
For 27.500 Mhz lambda=10.9091 m 1/2 lambda/100=5.5 cm
80
In this setup you have a horizontal polarisation, the total length of the wire is 11,07 meters
If you want to communicate with mobile units, with vertically polarized antennas then you must use vertival polariztion
Full wavelength: 300 / 27.555 = 10.887 x 0.94 = 10.234 m Top sections of antenna: 0.64 wavelength: 10.234 x 0.64 = 6.550 m for each leg
For 27.500 Mhz lambda=10.9091 m 1/2 lambda/100=5.5 cm
Antenna switch arduino for icom IC-7300 A solution built around an arduino nano and one of the readily available four relay switching boards
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