I finished building my Rockmite ][. It's running off of 3x 18650s, or 12v. I connected it to a MFJ-1840T and held the antenna horizontally in the air (also tried vertically) with my hand. I tried calling clean CQ on 7.030 mHz and get no response. I tried with and without a counterpoise attached to the MFJ. My nanoVNA tells me the antenna has an SWR of ~2. I tried seeing my signal on a websdr 100 miles away to no avail. I'm in a suburb.

I have lots of questions. I also don't know which of the following are necessary or not, or where to start.

  • because I'm holding the antenna, should I be expecting nvis contacts only?
  • is my hand wrapped around the antenna base heat shrink hurting things? What's the better way?
  • how sensitive is my setup to time of day?
  • would building a G5RV instead of the MFJ be the thing to get me some contacts? Thus focusing on the antenna instead of more watts.
  • would investing in a QRP SDR such as the RS-HFIQ make it possible to chase down band activity and move to more active frequencies to make a contact? Would this help me deduce receiver capability of my antenna setup?
  • are newer digital modes other than cw required to be successful in QRP?
  • should I join a club and being my setup to others to help me figure it all out with?
  • should I climb a mountain peak and try the same thing again?
  • do I need to figure out how to get the swr down?
  • I type for 2-5 minutes before giving up. How long would it take to get a typical bite (response)?
  • do I just need more watts? Am I attempting the rare or impossible? Is the rockmite just not usable in this part of the solar cycle without an amplifier?
  • is there something else I'm not thinking of that is making it impossible for me to make a contact?

I see what your problem is.

That's a 1.4 meter long, based-loaded, telescoping, end-fed vertical antenna. It has significant losses on 40 meters.

Furthermore, all end-fed antennas require a good RF return, such as a resonant elevated radial or counterpoise. Since you don't mention that, that indicates to me that very little of your signal is actually being radiated.

A full-size, center-fed, 40 meter dipole cut for 7.03 MHz is a little bit more than 67 feet long, and no counterpoise is required. I can almost guarantee you that you'll get some answers with one of those!

I strongly discourage using a G5RV for the reasons listed on the G3TXQ page about them.

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  • $\begingroup$ Thank you! You have now confused me though on the difference between a counterpoise and a radial. Is it a radial when the wire is touching the ground? $\endgroup$ – mh00h Jan 19 at 20:53
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    $\begingroup$ @mh00h Well, the difference is actually subject to a lot of debate. But one thing is for certain: one elevated radial is going to be far more effective than one radial lying on the earth. $\endgroup$ – Mike Waters Jan 19 at 21:07
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    $\begingroup$ @Mh00h For the purpose of this Question, "counterpoise" and "radial" are synonyms. Close enough, anyhow :-) $\endgroup$ – Chris K8NVH Jan 19 at 21:10
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    $\begingroup$ I wanted to report back that using a full size center fed dipole indeed fixed the issue. Thank you! I can hear all sorts of activity with it! I nobody hears me because my little .5W rockmite doesn't have enough power. Thanks again. $\endgroup$ – mh00h Mar 23 at 3:05

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