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40/80 dual band vertical dipole antenna update

Tempus fugit. I have not touched the antenna in the last week. I am still on vacation. The XYL is out visiting so I am enjoying being a bachelor again to the max. It feels good. No chores today. No housekeeping. Just me and my ham radio, my photography, my bicycle, my microwave, my wok and my TV. I get some exercise walking from the bedroom upstairs to the kitchen and shack downstairs. This is the good life. However, I have touched the antenna project as I found some antenna wire and nylon guy ropes all balled up in a corner of the yard where my landscape engineer had secured it, so today I will add some more wire onto the antenna and see where we can go. The antenna analyzer is back home so that will be deployed too. The antenna is tuned up just below 3.8 mhz with a 1:1 SWR, but the SWR on 40 is over 2 but under 3 at 7.135 mhz or so, totally unacceptable, since I never use antenna tuners. I have to remodel the antenna further to satisfy my requirements. The overall height of the ver

40/80 vertical dipole antenna feedback 2

The short 40/80 meter top and bottom loaded vertical dipole fed with one single feed line is finally up, but the bottom loading wire for 80 meters is to be replaced with real antenna wire which will be recycled from the existing single band 80 meter T-cap antenna. Nothing went according to the plan laid out for Saturday. First it rained, next it was windy, but the rain was the real show stopper. Negotiating wet grass and wet bamboo stalks across a dry river bed are not my idea of ham radio fun on a Saturday. So like the shuttle, take off was rescheduled for the next 24 hours. The self resonant frequencies on 40 and 80 were in band for starters, so I was not far off with my assumptions. The feed line is not the real length but should be close by about 4%, pretty significant but workable. The local signal reports indicate that I am not as strong as before, and I expect that, since both the vertical and horizontal radiation pattern should now be different, and the antenna is not yet tun

40/80 vertical dipole antenna feedback

All systems are go to install the 40/80 meter vertical dipole antenna today, if no rain. Rain is the one thing in the Caribbean that upsets everyone. Personally, I like the rain and it slows down, but does not stop my show. For some people it is the opposite, just the thought of rain totally stops their show. Rain to some people is like fire and brimstone. Of course for the Rastaman rain is quite something else. After serious consideration and contemplation I have decided why and where I will place, as in orient, the top and bottom loading wires for both the 40 and 80 meter antennas. It is not really critical because as long as you are 'out of plane' it is good bye to the high angle suppression. In this experiment I want to see if the allowed 'high angles' will give my antenna 'more ears' for local contacts. In theory it should, while maintaining the original low angle. I need to make up a new feed line, but I will use the old one which is good for 40 meters, bu

Old rigs never die - chapter 5

Most hams should be acquainted with the Sherwood Engineering Inc's Receiver Test Data Table found here , with an update stamp of 2 July 2009. This table can prove useful and helpful to most hams who are out shopping for a first, second or third rig. It could also set up some of us older hams for a little peer pressure. When we acquired that rig which is now down at number 45 in the Receiver Test Data table, we were unaware of the existence of this table, so we should not take it personal, nor should we let our ham buddies give us any unnecessary static. In days gone by the average ham could strive to buy the 'the top of the line' rig of the day for 2K, 3k or 4k uncle sam, sometimes with a mild stretch. It is a whole different story in 2009, and some hams may not be in a position to stretch, even though some of the eBay rig prices may seem quite reasonable to some of us. The 'new' top of the line ham rigs may now be well above 10k, and I would expect all of them to

new vertical dipole antenna experiment feedback

Getting Murphy out of the way was easier than I thought, but I am not taking any chances and have activated plan B, just in case. A week or two is much to far away to work on a simple antenna like this, so at lunch time today I am half way completed. I am converting my 28-foot 40-meter top and bottom loaded vertical dipole to this single feed line 40/80 vertical dipole. I had a vision of an alternate layout of this 40/80 single feed line antenna, and this will be tested later down. I envisage this present antenna experiment to be more labour intensive than usual, and I have installed a tilt over base, so that I will not have the hassle of 'storming' the mast/antenna, and 'lashing' it onto the fence any more, nor solicit any XYL assistance when it is breezy. I now have three [3] tilt over masts installed, and they are all spaced 34 feet apart and in line. Coincidence? Maybe not. In line the three [3] masts/antennas point to Japan and you can compute the broadside directi

new vertical dipole antenna experiment

It pays to revisit supposedly old documentation. Stuff that we have once read and sometimes consciously think that we may never need again in this lifetime. Fortunately for us, our subconscious does not subscribe to that line of thinking, and like the good computer it is, even though we may not appreciate it, continues to update and compile data on our behalf. When the time is right we get a flash of inspiration, a burst of knowledge, or whatever we want to call it, because all the pieces just fall neatly into place. It is not by accident, but many of us don't know that and maybe even more don't really care. I just had that experience a few moments ago, and my next vertical antenna experiment is shaping up. Some time ago I viewed this website and did not give it a second thought because I could not handle the center feed point for the antenna, nor the 70-foot vertical section. Today, some months later, I am on the web page again , the data is still the same, but I now see it fr

short top and bottom loaded vertical dipole again

I think I am on to something and I need to share it with everyone. It will do me no good to keep it to myself. I am of the view that I will be a better person if I can help someone in some small way to see the light at the end of their tunnel, and that has nothing to do with whether or not they can help me to see the light at the end of mine. Life and living is not about ME, but about YOU, and how I can help YOU to realize your full potential and maybe your destiny. In relation to our hobby of ham radio, it did not take me 40-years to recognise that it is all about basic principles, and the application of those basic principles. Some of us try to get as far away from the basics as possible, but if the "sophistication" sought after is not rooted in proper basic principles, you are wasting your time and money. I am no big time engineer, but I have recognized that most of the ham transceivers of yesteryear were built to great specifications, and some still fetch a good price on