I'm building a contest station and the time has come to make a choice of 160m TX antenna. Looking at DXE Thunderbolt I note that the capacity hat extends to a significant distance down the vertical s
Dave that seems expensive and not cost effective. I would use two scaffold 20' poles plus a lighter gauge top section of similar dia. You can buy aircraft grade DIN tubing 6082 which is slightly bett
Author: Rudy Bakalov via Topband <topband@contesting.com>
Date: Sat, 5 Dec 2020 09:24:16 -0500
David, Are you thinking of buying from DXE and importing? If yes, you may as well consider buying the aluminum from them and build the vertical exactly the way you want it. This is what we did at HQ9
Author: Rudy Bakalov via Topband <topband@contesting.com>
Date: Sat, 5 Dec 2020 09:35:52 -0500
P.S. If your vertical has a good set of radials, you will see about 35 Ohm feedpoint impedance. You may want to wind your own unun using Jerry Sevicks cookbook http://www.introni.it/pdf/Amidon%20-%20
Or reduce the loading to present a capacitive reactance at the feedpoint and shunt it with an inductor. Functions as a step up L-network and presents a ground at DC. That's what I do here. Wes N7W
The DX Engineering Thunderbolt antenna includes a means to resonate and match the antenna using a series inductor and a shunt inductor. *It does not require a balun*. See the manual: https://static.d
Hi David, I live in a windy area with 100km frequent wind gusts in the spring. I bought a DXE heavy duty 80m self-supporting tilt-over vertical on the advice of a professional tower guy. It was expen
I have one of the DXE 80m verticals and it is great. The ability to crank up and down is nice, although I have never taken it down since I put it up. The thing is a tank! I have an inverted L for 1
I refined the DX Engineering Thunderbolt EZNEC model to be exactly like the actual antennat by changing the capacity hat wire size. It is resonant at 1930kHz. 2.15uH of series inductance tunes it to
Yes and no. The sloping hat reduces the effective height, which reduces the radiation resistance, thus the feedpoint impedance, but most of the radiation is from the part of the antenna where current
David, the capacity hat does cancel some radiation. Think of RF current going up the mast and down the top hat wires. The magnetic fields partially cancel. Without the capacity hat wires the 55' mast