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I understand that, but a PCB is (of course) not just for professional) looks. You see on all RF circuits the GND-stitching all over the place :-) But of course, if you experiment or build prototypes

I suppose you are right. By the way if you search on "RF Demonstration Kit NanoVNA VNA RF Test Board Filter Attenuator PCB RF Test Board Vector Network Analyzer Learning Tool Kit" you can find a test

Sorry Barry and Dave, I read your posts while half asleep and now realise you are talking about an end fed, not an end fed half wave! Anyway, I thought I'd include details of my own measurements to

It should be noted that an antenna can be an "end fed" without being an "end fed half wave." Antennas that are not half wave but are, in fact, end fed, are often used with a 9:1 balun. 73, Jim KX0U

If you are using a 9:1 unun then it's not an end fed. My EFW4010 gets me around the world on 100W SSB. My measured SWR is the same as simulated by EZNEC. If you're interested I can send you details

Thanks for posting, Barry! So you are discovering there really is no "end fed" resonant antenna. The proof is in the measurements as you show. So why is this abortion so popular??? ONLY, and ONLY

Looking at the photo on their website, the switching is easy. They use a 2-turn primary and 16-turn secondary winding on the toroid. The switch would simply take the antenna output from taps on turns

I'd try swapping various USB-C <> USB-A cables before cutting up a cable. From past experience I've found some cables are not made with copper wire that you can solder to but aluminum wire or

Hi Don, I wonder how they switch that. it looks like an ordinary ferrite core coax wound 1:1 balun.. I like the concept though . Bryan, n0luf

I have a 40m wire on a 9:1 which it mostly flat, strung between 2 30 poles, is sags a little in the middle. I had a counter poise on and it was just okay. I removed it and now have just a choke at

Peter, Oh geez, of course you're right, I put up three antennas that day and had to move them around. I'm thinking of what started as on inverted L and ended up being a rather lazy endfed. No

If done properly, yes. The radiating portion should be in the clear well away from other conductors and also common-mode choked at an appropriate point. If either is not done there are problems. There

Well, it is if it’s designed that way. There’s a whole bunch of half wave dipoles where the outer side of the feedline is half the dipole, and the center conductor is the other half. “Sleeve

It should be mentioned that using your coax as the counterpoise is not best practice. 73 -Jim NU0C "Barry K3EUI" <k3euibarry@...> wrote:

I use the MyAntenna 10-75-2Kw in an inverted L, 50ft LMR-400, 30ft rise, then 100ft horizontal at about 30ft. Works great. 73, Brian W1BKW

*I've had a? MyANTENNA? 130 ft? end fed ? 1/2 wave? with?? 49:1 UNUN? up for one week and it works but is very "touchy" to tune up around 3580 kHz* *I took it down, added wire, and set up a

What is a premium core? An inverted-L typically has a impedance <50 ohms and a endfed halfwave is high impedance, so neither a 1:9 nor a 1:4 transformer could be right. 73 Peter, DJ7WW

I've used them before - great company. In my application and if I remember the part number correctly it was the BWDS1.5-80 with the stainless steel wire. I had that installed as a backup to a CMV-604

I just substituted a 9:1 Palomar Engineering UNUN with 100 ftRG213 (counterpoise) and changed the wire length to 155 ft in a large horizontal loop (around my back yard). Everything looks better than