A new HF9V installation

[K3GHH]

A week or so ago I installed a new HF9V, with the TBR-160-S coil, on the peak of the roof of my two-story house. (The lot is small and does not lend itself to ground mounting.) I thought I'd pass along the results of some of my tuning. As you'll see, I'm far from done yet! I'm not wild about going 35' up the ladders to that roof, and lifting the HF9V vertically off and back onto its mounting post... but it has to be done. There are 2 radials on 80 and 2 on 40/15 (separated by only about 45 degrees, due to space and support issues), and 1 each for 30, 20, 17, 12, and 10.

Initial SWR dips in/near ham bands, using MFJ-269B and original Butternut manual settings:

1.942 (SWR=1.6); 3.926 (1.1); 7.352 (1.1); 10.770 (1.6); 14.600 (1.8 ); 19.920 (1.2); 20.020 (1.1); 25.750 (1.1); 28.370 (1.2), and 50.750 (1.2).

I'm a CW op, with radials cut for 3.550, 7.030, 10.120, 14.030, 18.100, 24.900, and 28.030. After a visit to the roof with the 269B, I compressed most coils (the 80m and 40m 3" and 4" respectively) to reduce the frequency and found these dips:

1.804 (SWR=1.2); 3.540 (1.3); 7.072 (1.4); 10.592 (1.1); 14.322 (1.6); 19.400 (1.4); 20.631 (1.5); 25.706 (1.1); 28.517 (1.3); 50.410 (1.2).

As long as I was already on the roof with my tools, I probably should have taken it down again and made further adjustments but was getting tired and cold. The 160 dip is actually now lower than my goal; 80 is almost exact; 40 is way better but still a little high; the higher bands still need work (need to reduce everything, except raise 15m).

Just a progress report... I don't see any real problems, just some work yet to do. This seems like an excellent antenna.

[KB8VIV]

I had an hf6v up for many years, ground mounted and it was a bit of a pain to tune, as when I'd get 40 mtrs dialed in, it would change the tuning on 80.  Once I got it tuned in, I was very happy with it. 

Good luck.

Steve
kb8viv

[K5LXP]

The

As long as I was already on the roof with my tools, I probably should have taken it down again and made further adjustments but was getting tired and cold.

What I do is set up a fiberglass stepladder on the peak of the roof next to where my butternut is mounted so I can reach the adjustment points.  Then I don't have to keep laying the antenna down to make adjustments for anything once 10 and 15M is tuned.  17M is the most touchy to tune and anything under 3:1 at the dip is considered as good as you're going to get on that band.

I suspect your compromised radials will actually help with bandwidth and low SWR but I'd still try and get the "dips" as close to where you want them to maximize your realizable efficiency.


Mark K5LXP
Albuquerque, NM

[K3VAT]

... I'm a CW op, with radials cut for 3.550, 7.030, 10.120, 14.030, 18.100, 24.900, and 28.030. After a visit to the roof with the 269B, I compressed most coils (the 80m and 40m 3" and 4" respectively) to reduce the frequency and found these dips: 1.804 (SWR=1.2); 3.540 (1.3); 7.072 (1.4); 10.592 (1.1); 14.322 (1.6); 19.400 (1.4); 20.631 (1.5); 25.706 (1.1); 28.517 (1.3); 50.410 (1.2).

Just a progress report... 

Very good!  While low SWR doesn't guarantee that your signal out is optimum, those are indeed excellent readings (except for 17M thru 12M - which may be expected).  Personally, I wouldn't mess with it anymore.  If you have the inclination at some future time you can always add additional tuned radials and optimize the layout per standard references.

Thanks for the update.  73, Rich, K3VAT