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Messages - dylan

Hi everyone. I had a recent opportunity to take an MTR5b and 40m EFHW setup deep into the wilderness. Similar setup to last year's "radio vacation" ( The 40m EFHW was tuned via QRPGuys EFHW tuner, with driven element / counterpoise lengths from their recommendations. I was able to get the high end of the antenna up about 40 feet thanks to some conveniently placed trees and topography. Sounds like a great setup, right?

I found that I could "hear" stations all over the US at 0200 UTC (local time ~ 7pm) but could not make contact with a station about 50 miles away that was listening/transmitting. I used VOCAP ( to estimate the potential for said contact, and the predictions left me confident (see attached forecast). It seemed like 40m at 0200 UTC would be within the realm of possibility when using 1W CW on my end, and 15W on the other end. Note that the other station was using a 40m doublet at about 20 feet elevation, north-south orientation. I was north-east of the other station.

A couple of observations and questions for the group.

  • The EFHW + tuner combination seems to do well when the tuner is elevated at least 3-4 feet off the ground, any closer and it is difficult to achieve and SWR less than 2:1.
  • What kind of theoretical radiation pattern can one expect from an EFHF? I recognize that there are over 1,000 answers depending on the local conditions, but could there be any rules of thumb to go by? For example, one can expect maximum signal strength in the horizontal plane at 90 degree angles to the orientation of a 1/4 wave dipole at resonance.
  • Was the skip distance under those conditions / antenna the likely problem (overshoot) or antenna directionality?
  • Is it possible to achieve NVIZ-type communications with a EFHF?
  • Are gound-losses too high for NVIZ to function properly at < 5W of power?

Overall, I'd bring the QRP kit (MTR5b, 40m EFHF, QRPGuys tuner, mini-paddle, ear buds, 9V battery) on my next backpacking trip as it contributed very little weight.

I'll have it out again next week in case anyone would like to schedule a QSO on 20/40m.


Net Activity / Re: Radio Vacation
August 06, 2018, 09:51:53 PM
Some updates, still trying to figure out the radiation pattern to expect from an EFHW antenna. Over the last 20 years most of my antennas have been half-wave doublets.

The 20m EFHW was setup as a "sloper" with the feed point at about 5' from the ground and terminating at about 15' from the ground. Connecting this kind of antenna to the EFHW QRPGuys tuner has always been a challenge as there aren't many options for strain relief. This time I tried something new, as I had an overhead shade that I could use as an anchor. I put a single loop in the antenna wire around a bowline tied into some paracord that was anchored from above. This transferred tension from the "long part" of the antenna wire and left me with about 3' of slack which could be connected to the tuner (attached image). I suppose you could do something similar with an anchor from below, perhaps tied to a tent peg.

I used 26 AWG "silky" wire in this latest experiment which was far lighter and easier to work with than my previous attempts with 14 AWG stranded copper wire.

The counterpoise wire was tossed out on the ground below the driven element. Tinkering with the antenna analyzer seemed to suggest that this gave the best SWR and broadest local minimum in the SWR curve.

Some questions come to mind:

1. Does this kind of strain relief (e.g. a single loop of wire) affect tuning characteristics? It didn't seem to, as my antenna analyzer reported reasonable SWR curves over the 20m band.

2. I found this neat page ( on the theoretical radiation patterns for sloping EFHW antennas, but it still isn't clear to me what the resulting radiation pattern for my recent setup should be (in theory). Based on the linked table ( It would appear that this antenna, hoisted to about 15' (~ 0.25 wavelength) radiates most of the energy straight up! That doesn't seem right, or does it?

Net Activity / Re: Radio Vacation
July 31, 2018, 07:49:27 PM
Well shucks. Called CQ for about an hour around 14.060, +/- a little and no replies. Otherwise perfect day in the woods. The EFHW tunes up with an SWR around 1.3:1. The antenna is pointing due south and elevated 10-15' above the ground.
Net Activity / Re: Radio Vacation
July 30, 2018, 11:26:15 AM
I suspect that you have "heard" this radio before, I bought it from Ray. I'm still trying to figure out the best way to attach the EFHW to the QRPGuys EFHW tuner so that the antenna wire isn't pulled out from under the wing nut.
Net Activity / Radio Vacation
July 29, 2018, 05:56:38 PM
Hi folks. Thanks for sharing so many great stories, reviews, and ideas.

I am planning to be on 20 and 40 meters CW this week, operating with an MTR5b and EFHW antenna from the north coast of California. I'll likely be hanging out near the middle of the CW portion of the bands, between 1-3pm pacific standard time. I think that is a -7 GMT offset. I'll send a photo and review of my temporary station once I get it setup.