So I Made My First Random Wire Antenna

Oh what fun this has been!

I have been very happy with the loop antenna I have, but never could overlook the fact that for the 80 and 40 meter bands, I would need a much bigger loop (which is actually in the plans). After contemplating for the purchase of an automatic antenna tuner which could also support wire antennas and similar, I however settled on a manual tuner, namely MFJ-971.

80m TX coverage for the wire antenna

I set up a 2.5 sq. mm insulated copper wire – roughly 20 or so meters – from the balcony, sloping downwards to a birch tree. As a sort of a counterpoise I used the balcony rail. Maybe I am a lucky child but it worked really well, I was able to work FT8 on 80 – 40 – 30 – 20 – 17 meters with this combination.

The MFJ-971 brought me to the 80/40 world which as an apartment dweller I considered nearly impossible, in particular in this QTH which again I thought was beyond any help as a location.

Lesson learned, never give up, try – try – try – .

The fishing rod is not used in this setup (you can see however the birch tree to which the wire runs, in the background). It was used with a quick ad hoc long wire as a first test for the MFJ-971, just 10 meters supported through the tip of the telescope rod and then hanging downwards. That was far from optimal, but as an RX antenna was already a major improvement on 80 meters.

The wire is at approximately 4 meters height at the tree end

The IKEA furniture often comes with a set of tools. This is probably a familiar handle which makes for a great insulator for wire antennas

Another piece of impromptu equipment was this hardware store general wall hook, which I use for securing the end of the (insulator – wire – hook run) to the tree, to keep the hot RF wire a sufficient distance from the trunk and leaves – that black wire attached to it is not the antenna wire

Got my first RF bite today as well, during early setup and testing / adjusting. Other than that, no negative side effects noticed. Zero indications of “RF in the shack”.

I think there will be version 2.0 later on, with different routing and direction of the wire, and likely an antenna switch – I’d see use for both the loop and the wire – and further QSO’s. To sum this up I’d like to say that the wire antenna clearly exceeded my expectations, and the MFJ-971 works like a charm. I have used it with up to 50W of power.

Tuning the MFJ-971 is quite easy as I have had a relatively lengthy experience so far with the MFJ-936B, despite being different beasts the controls and “feel” is similar, both respond to tuning in a logical, repeatable way.

Received also some MIL spec (i.e. genuine military) vertical and wire sets, second hand, which I will examine in greater detail (the vertical in particular) to see if I can duplicate the Chameleon MIL whip w/extension.

From Ebay I ordered military surplus N.O.S. PRC-77 antenna, and some related equipment. While originally intended for higher than HF frequencies, I am looking at those parts as source material for fabrication. I have some plans for a get-and-go vertical HF antenna, probably for a vehicle mounted (stationary) usage. More on these later.

73 de OH2BNF, one happy wire antenna fellow

 

WSPR/FT8 experiments with a balcony mounted 1-meter loop antenna

Let me be honest here – I had to – initially – resort to 100W and careful tuning and positioning of the antenna to reach the most distant locations.

In this picture, there are accumulated reports over several hours

BUT THEN I REDUCED THE POWER TO 5W WITH NO SIGNIFICANT LOSS.

After reducing the power to 5W I waited shortly after a TX and looked at “past 10 minutes”

There are so many variables involved, including the band conditions (I am mostly on 20m band) that there is not much to be deciphered from the results, except that it is great fun using the WSPR (Weak Signal Propagation Reporter) and related web site at http://wsprnet.org where results are near real-time, as such quite useful for testing out different settings.

Altogether in addition to the first somewhat long-distance FT8 QSO to Oman (A41ZZ), past few days have yet again proven that one needs to spend considerable time with the setup, learn to use all the components – the whole stack – and test nearly endless combinations. In regards to the situation at QTH and equipment used, I tend to think that despite initial excessive power rating for WSPR or FT8, I can still be relatively happy at the outcome.

It would however be important to reduce the power as much as possible, as that would indicate better skills and as a matter of fact many use diminutive power ratings, when operating these modes.

Here’s the antenna setup as used on the balcony during a previous test, which indicated much better reception from a distance of about 1500 km’s for voice communications. But what has really been the most important thing is to tune the antenna for the given position and the frequency, as loop antennas tend to have a very narrow bandwidth.

In general I need to bite the bullet and start experimenting with various wire antennas and verticals. Those may not be possible at the QTH, so it’s going to be mobile time, once the Buick has the broken front wheel bearing replaced, and we will be off to summer vacation. But for an apartment dweller, the loop has certainly been a success, albeit with a long learning curve.

– 73 de OH2BNF