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Did you calibrate out the coax before taking these measurements? Doing so would eliminate the coax from your possibilities. To do so you need to put your calibration loads on the far end of the coax and recalibrate the device with the coax attached. It may take one or two additional adapters...

How big is the change on the field strength meter? How many radials did you use with that antenna? Were they horizontal or angled down? A field strength meter will be far more sensitive than, say, an s-meter. Used properly, most can pick up on changes that are very small, well below the...

VNA stands for "Vector Network Analyzer", think of it like an advanced antenna analyzer. Most tend to be pretty pricey but you can get a nanoVNA for around $50 or $60 these days, which is amazing based on what antenna analyzers cost not to long ago (and really still even today). If you already...

Wow, you dug these out from the past, even a post from Doc's account which I haven't seen post in a decade or more... Hope hes doing well. Its good to see people still go back and read said posts, a lot of good information in this forums history... What I was talking about has nothing to do...

I know the capacitor in the K40 is 130 pF. I don't know anyone wo had taken the K30 apart and haven't found any info on said capacitor online so I am not sure about that one. Likely to get that information, you will have to have someone take apart a perfectly good K30... The DB

For any length of antenna shorter than 1/4 wavelength, there is a loading coil that will, by itself, get you resonance. However, when you start shortening antennas to this degree, just because you are at resonance does not mean the SWR will also be at a use-able level. Because of this...

Is it possible that this is the case? Yes. So the next questions becomes... How large of a roof would it take for something like this to happen? And then... Are their any vehicles that are actually that large? The smallest size would this would be possible would be be a roof that is larger...

Skyport, I didn't put radials on those models. I'm pretty sure I did at one point just for testing purposes, but I don't recall the results, which generally means that they are underwhelming as if there was a huge difference somewhere I would definitely remember them. Homer, we are on a...

To start with, with all due respect, in the context of your post, that was on topic... But to answer the rest... When an RF signal travels up a feed line, unless a certain condition is met, impedance and reactance (typically shortened to the variables R and X) change as well. At distances of...

So you think that just because a company put it out that it is absolutely true and must not be questioned? When studying the Astroplane patent, an antenna patent that was held by the very same company, several of us have demonstrated several things mentioned in said patent were objectively...

Oh boy... This is a topic that has been known to cause many... heated discussions... yea, I'll leave it at that. The one and only correct length for coax in an antenna setup is the length it needs to get from the antenna to the radio. I will generally add an extra foot or two to make...

If you go to youtube itself to watch this video, I put in a rather lengthy description of what was happening with the various parts, and how they were working together. The DB

They are electrically 1/4 wavelength. The entire antenna is essentially a loading coil, which lengthens the 4, 5, or whatever foot length the antenna is to 1/4 wavelength. They only get off calling it 5/8 because they design it to use a physical 5/8 length of wire. If these antennas were...

The context of my post had nothing to do with how useful or not the ground plane kit was, it was commenting on weather or not the antenna met the advertised claim of being a "balanced antenna". Therefore, at best your reply is out of context. Speaking to it anyway... As you have a rather...

I hadn't really considered the voltage on a capacitor changing with the changes in dielectric thickness. When it comes to the effect of inductance and capacitance, my knowledge comes more from studying their effects on the antenna directly rather than working with the devices themselves. As...

A few notes on brandon7861 and SuperLid's conversation. Starting with Brandon's side, I just looked up his numbers for the capacitance of a triple magnet mount, and assuming the triple magnet mount has three inch magnets, they are close to accurate (if anything I would say he rounded the...

I'm not familiar with a new Astoroplane from then, unless you are referring to their current model Top One which they conveniently advertise as an Astroplane on their web site, which is very different from the old Astroplane antennas. IMHO this version of the antenna is closer to a Starduster...

For a given magnet size, the higher the frequency the better magnet mounts of the same size functions. At CB frequencies, a 5 inch magnet is barely able to do the job. At 2 meter frequencies, even a three inch magnet is far more effective than a 5 inch magnet at CB frequencies. Also, just...

That looks to me like a phasing stub, not a coil like on the radials. Those are typically used when making collinear antennas, to keep adjacent electrical 1/2 wavelength sections in phase, and are thus electrically 1/2 wavelength themselves. I'm not sure that is what it is doing here though...

DC grounded antennas tend to have less static, and thus are said to be quieter. This is essentially because the cause of the static has someplace else to go rather than build up on the antenna itself. This isn't the only technique of lessening how much static you hear, nor does it work on all...