A choke balun cares less if the load is reactive, only voltage baluns (like the W2FMI style) are load impedance critical. Placing a choke balun at the input of a tuner does nothing for balancing of
Brian brings up an excellent point. I don't want to discourage anyone from using a loop because they do have the advantage of being easy to feed, but gain is overrated! Brian sez: I certainly agree!
Hi Mike, Think about what the goal is. You want everything to move up together at the same rate. The big problem is when there is a potential difference between different things. If my feedline pass
I wonder why anyone bothers with a 80 meter yagi, especially a linear loaded yagi, when it is so simple just to install a couple reversible wire beams or phased arrays. The only case I can see where
The secret is the height, not the antenna. I always wonder though why so many manufacturers use linear loading. 73, Tom W8JI W8JI@contesting.com List Sponsor: Are you thinking about installing a tow
Hi Ford, A large part of the problem is because once an arc is started, a very much lower voltage sustains the arc. Sometimes a breaker actually has to open and reset to stop the system from arcing.
Modelling prompted me to install a 318 ft tower, and that probably was one of the worse investments I ever made. But hey, if you don't try one you never know. Don't sell a vertical short without try
The main advantage of the earth is the cable is tightly coupled to earth around the cable, and is very unlikely to have much potential difference between it and earth from distant strikes. Put simpl
That is generally the case, the exception would be if the shield had a high resistance or open connection...or of course if you had a large antenna hanging on the cable that was not balanced for DC.
Hi Tom, Hi Tom, How far are you verticals from other vertical metallic structures, and have you checked the patterns? How good are your ground and feed systems? How traditional are your verticals? 73
Hi Tom, Like most cases, the installation is too complex to tell what is causing what. Even without any measurements, we know that is a situation where more than one "antenna" radiates significantly
Just be sure the copper strap is not braided or woven, especially if it is subject to weather! Use solid smooth copper flashing for all important grounds! 73, Tom W8JI W8JI@contesting.com List Spons
Hi Mel, There are a dozen solutions, but remember these rules. If you use transmission lines: A *mismatched* feedline only shifts phase the amount of the length when the line is an exact electrical m
Is it feasible to use coaxial cable as the series capacitor in a Assuming a cable no more than 1/4 wl long: The cable always looks like more capacitance than it measures at dc Pete, because any *ser
True enough. That's a good suggestion! If you parallel enough cables it starts to look like a regular capacitor...and behave like one. Loss decreases and capacitance is less frequency critical. 73,
I'm planning on using pressure treated 2x4's to support some Beverages. I'll just poke some holes in the ground with my tractor's post hole digger attachment, and drop the 2x4's in. Does anyone have
Hi Tom, Inside photos would be nice. I don't know why every manufacturer doesn't do that. Is this tuner built with new parts, surplus parts, or used parts? It looks sorta surplus, with the big knife
Bill sure has it right. We should always model the antennas to pick stacking distance! We used to do this on paper before it was common to use personal computers to model antennas. You can do somethi
Hi Yuri, No. They are not directly related. What if I stacked two dish antennas? What is the boom length of a dish? For example, your own super 10dB-over-a- 5-element-yagi-superrazor beam antenna wou
I didn't intend to start an argument, just to point out HOW it works. Some people like to know how or why something happens, some people like to just plod along clueless about how or why things work