I am a beginner with not much experience in HF. My shack consists of a Xiegu G90 connected with 20ft of RG-8x to an MFJ 1982 end fed half wave antenna. There is a small coil of coax next to the matching transformer box. The radiating element is suspended in an inverted V configuration with the midpoint around 30ft above the ground. The unun is connected to the eave of my house around 9 feet in the air. There is also a 10ft counterpoise connected to the matching unit. My problem is that I am only hearing the very strongest signals on some HF bands, On the other bands, I am hearing nothing at all! I know that the manual says to leave the matching unit near the ground, but performance is maybe even worse when I do that. The SWR on all the bands it covers is very good, never exceeding 2:1. I was wondering if someone could possibly shed some light on my predicament. Thank you all in advance, Levi, WH6GBR

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    $\begingroup$ Hello Levi, and welcome to ham.stackexchange.com! $\endgroup$ – rclocher3 Jan 12 at 1:33
  • $\begingroup$ @WH6GBR do you hear noise, just no intelligible signals, or absolutely nothing, just silence? Can you hear some HF broadcast stations? What does the S meter say, if you have one? $\endgroup$ – tomnexus Jan 12 at 4:22
  • $\begingroup$ Hello tomnexus. I can hear some stations on both ham and broadcast bands. For example, I can clearly hear FT8 on 14074 khz. I believe that the noise floor is around an S4 on receive. I was concerned, after looking at a webSDR node near my QTH because it was picking out much more signals than my antenna was. I can hear only the very strong signals I saw on the websdr. Thank you for your response. $\endgroup$ – WH6GBR Jan 12 at 8:30

First, what bands are you listening to? You should hear activity on roughly 20m – 40m during the day (and 15m sometimes), and 40m – 160m at night. This is close to the bottom of the sunspot cycle, so signals are often fairly weak, but there should be a few loud stations on 20m and 40m.

Your antenna would do better to be higher, but it's high enough for starters.

Your biggest problem is most likely that it's end-fed, and that it has such a tiny counterpoise. Marketing claims aside, end-fed antennas are finicky and difficult to feed efficiently. Also a transmitter trying to transmit into a high-impedance load needs an efficient RF ground to "push against", and your counterpoise, a single wire a fraction of a wavelength long, doesn't offer much of an RF ground. Your coax to the feedline would radiate if you transmitted, and you would probably have RF in the shack, which causes all sorts of weird problems with other electronics nearby. Poor transmit antennas almost always make poor receive antennas (there are exceptions), because if power doesn't get out efficiently then it doesn't get in efficiently either.

If you can, try putting up a dipole antenna, or a variation of a dipole antenna that's fed in or near the middle, with a good balun. Raising the coax to the center of the antenna might be tricky, and you might need an antenna tuner to get a good SWR, and you might not have very many bands; but you'll be amazed how much better it works than your EFHW, and you won't need a counterpoise for it.

  • $\begingroup$ Thank you very much for your concise answer. I appreciate it. I will try to increase the length of my counterpoise. In regards to the impedance, I think that the matching transformer is doing a very good job of matching it to 50 ohms, as I said, I am getting SWRs of less than 2:1 on most bands. As far as your dipole suggestion, do you think I could use RG6 efficiently with it? I understand that a dipole is around 72 ohms, so would a 75 ohm coax make much of a difference? I ask this because I already have a long length of this coax that I am currently using for a 20m vertical. Thank you again. $\endgroup$ – WH6GBR Jan 12 at 2:58
  • $\begingroup$ I disagree that it's the antenna's fault OP isn't hearing anything. Any piece of wire longer than a few metres should allow you to hear most things on HF. Matching is also not very important. It's possible that the local noise is strong, and some antennas (yagis on tall towers) are better than others, but most likely the bands are just dead. For transmitting, you're absolutely right, better counterpoise and matching are important. $\endgroup$ – tomnexus Jan 12 at 4:20
  • $\begingroup$ Thank you for the feedback. I will try to increase the counterpoise length a bit, what do you recommend for 80m? I might also try a bit of RF shielding in the shack. Have a nice day, WH6GBR $\endgroup$ – WH6GBR Jan 12 at 8:33
  • $\begingroup$ That's an excellent point about noise @tomnexus. I shouldn't write answers late in the day... $\endgroup$ – rclocher3 Jan 12 at 15:30

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