I am glad I found your video. I live in a small yard in North Carolina. I did my first experiments yesterday with an inverted L antenna and a 131 foot counterpoise. I made my first 160 meter contacts yesterday. I have some work to do, but it is a start. I learned some new things to try from your presentation.
Nice video Rick I built the FCP for my very low top band inverted L about 2016 and its still attached to my fence, my bottom fence is only about 11 metres wide so mine folds up both sides coming back towards the house. I did some tests with a now SK amateur comparing the FCP counterpoise with traditional earth rods and grounds radials. The comment I got back was also “your much louder now”. I also constructed a half sized FCP with a transformer for 80 metres with half the turns and this also worked. My inverted L is a temporary winter aerial so very easy to get matched.
I am interested in a 80 & 160 m antenna and they are on my to do list one way or another. I am strictly 20 watts or less so I aim for an efficient antenna. I had been a user of Mag Loops on receive & gave a transmitt version a go recently. For efficiency I used 4 inch diameter aluminum dryer vent tubing & 3/4 inch copper water pipe for the sense or inner loop. The vent tubing is surprisingly pricey at $8 a two foot piece thus due to price and space issues I made the main loop 4 feet square. Having never built one for transmitting I was not sure if I could by using the simple sense loop achieve a good impedance match. Indeed by trial and error I did. Apparently the larger the ( inner loop's circumfrerence divided by main loop circumference ) the lower the impedance thus a square of 3/4 copper pipe with a 7 foot circumference started giving me impedances that allowed for 1.3 or less SWR readings. I should probably learn to use my nano vna and see what the Smith Chart produced indicates & I will. Right now I have a rather large old double gang high voltage tuning capacitor with a smaller one in parallel giving me fine tuning. This is doing a bang up job on 40 meters for receive and while I can get great impedance matches I have not yet tried transmit & at 40 meters its only supposed to be 27% efficient. I really built it for 20 meters where it should be 79% efficient according to the online calculator. My capacitor is too large at the moment for 20 meters, thus shortly I will look for and buy a high voltage 30 or 40 pf max variable capacitor. Thanks for the info, kc2wvb
I am glad I found your video. I live in a small yard in North Carolina. I did my first experiments yesterday with an inverted L antenna and a 131 foot counterpoise. I made my first 160 meter contacts yesterday. I have some work to do, but it is a start. I learned some new things to try from your presentation.
Nice video Rick
I built the FCP for my very low top band inverted L about 2016 and its still attached to my fence, my bottom fence is only about 11 metres wide so mine folds up both sides coming back towards the house.
I did some tests with a now SK amateur comparing the FCP counterpoise with traditional earth rods and grounds radials. The comment I got back was also “your much louder now”.
I also constructed a half sized FCP with a transformer for 80 metres with half the turns and this also worked.
My inverted L is a temporary winter aerial so very easy to get matched.
Hi from Portugal,
Very interesting!
Peter
CT7ADL
I am interested in a 80 & 160 m antenna and they are on my to do list one way or another. I am strictly 20 watts or less so I aim for an efficient antenna.
I had been a user of Mag Loops on receive & gave a transmitt version a go recently. For efficiency I used 4 inch diameter aluminum dryer vent tubing & 3/4 inch copper water pipe for the sense or inner loop.
The vent tubing is surprisingly pricey at $8 a two foot piece thus due to price and space issues I made the main loop 4 feet square.
Having never built one for transmitting I was not sure if I could by using the simple sense loop achieve a good impedance match. Indeed by trial and error I did. Apparently the larger the ( inner loop's circumfrerence divided by main loop circumference ) the lower the impedance thus a square of 3/4 copper pipe with a 7 foot circumference started giving me impedances that allowed for 1.3 or less SWR readings. I should probably learn to use my nano vna and see what the Smith Chart produced indicates & I will.
Right now I have a rather large old double gang high voltage tuning capacitor with a smaller one in parallel giving me fine tuning. This is doing a bang up job on 40 meters for receive and while I can get great impedance matches I have not yet tried transmit & at 40 meters its only supposed to be 27% efficient. I really built it for 20 meters where it should be 79% efficient according to the online calculator. My capacitor is too large at the moment for 20 meters, thus shortly I will look for and buy a high voltage 30 or 40 pf max variable capacitor.
Thanks for the info,
kc2wvb
73's🎙KD9OAM🎧📻📡
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