Thursday, March 28, 2019

About the HF5B

Well it has been a while I inspected the Butternut HF5B in the mast. Last time I really used it was on 17m in QSO with XX9D. I'm mainly on 60m and use other antennas as you know. But with the upcoming CQ WPX SSB contest this weekend I decided to take a closer look. After a few storms the capacitors are hanging down a bit and 12m doesn't have a good SWR. Actually I thought this antenna would break this winter but it is still hanging. I still have a issue that 20m does not have really a front/back difference and only a slight front/side difference when turning the antenna. Since I had to go to the dentist this afternoon and was home early I decided to have the tower down for a closer inspection and possible do a little "tuning".

First of all I made shure all connections were still solid. I noticed a
loose 12m gammarod which was tightened with a extra washer. Hopefully that was the cause of my bad 12m SWR? I also made a small isolation tube to support the 2 20m capacitors.

To get a better F/B ratio I guess I need to increase the length of the reflector, So I did move the hairpin a little to get extra length, On the second thought.....moving the capacitor further to the outside of the reflector might have a better way?





Actually I really don't know what to do to get better results on 20m. After I got the tower up again I did some tests. Surprisingly nothing changed SWR wise. Even 12m is still the same...And the F/B ratio? Well nothing changed at all. The HF5B is a strange antenna. Not that it is really bad but it is not good either. Bernard PB7Z has a similair HF5B and used it with good results. He has a reasonable F/B ratio on 20. But it seems he has an older type HF5B that is a little different from what I use. Could that be the difference? I will use the antenna in the CQ WPX SSB contest since it works well on 15m and 10m. But when the ES-season is there I will remove it and do an exchange again for the 5 element 6m yagi. If the HF5B is going to make it into the tower again I doubt it. I think I have to look for another 5 band directional antenna.

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