Author Topic: 60 meter end fed half wave and an update  (Read 3721 times)

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Lamewolf

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60 meter end fed half wave and an update
« on: January 20, 2016, 06:07:48 AM »

Gang,

 

Recently I put up a sloper for 160 meters and have found out that 160 is just too noisy at my location and I'm not using it much at all.  So when time allows, I will be shortening the wire to somewhere around 88 feet which is a half wave on 60 meters and will be feeding it with a little homebrew Lmatch circuit.  Got the Lmatch built last night and put it on the analyzer and I can get a good match with anything from 1000 ohms to 5000 ohms just by adjusting the variable capacitor.  So once I get the wire the right length, I will put the matching unit in place and fine tune it for 60 meters.  The low end and feed point will be about 7' above ground with the high end around 65 to 70 feet.  60 meters seems to work well for regional comms, and this way I won't have to worry about fiddling around with a tuner like I do when I use my off center fed dipole there and being a half wave it will be less dependent on a ground or counterpoise but the ground side will be connected to my ground system for safety.  So has anyone else used an EFHW on 60 meters ?

UPDATE:

The 60 meter end fed half wave (88' of wire) is a success.  Dropped the high end of the 160 meter antenna down yesterday and shortened it to 88' and pulled it back up, then installed the Lmatch at the feed point.  Before I mounted the Lmatch, I put a 4400 ohm carbon resistor across the terminals and adjusted the variable cap to get a 1:1 swr, then once mounted and the wire was connected, I checked it with the analyzer and it had only risen to a 1.2:1 swr on all 5 channels.  The 1.2:1 stayed the same both with and without the ground wire connected indicating that the wire length is resonant, but I did leave the ground wire connected because the Lmatch also has a 100mH choke between the antenna terminal and ground to help bleed off any static charges to ground.  Eventually though, the Lmatch will be replaced by an impedance transformer similar to the ones used in the Par EndFedz antennas, but mine is being wound on an FT240-61 core.  The transformer should allow operation on 60 meters and hopefully be close enough to also use on its second harmonic on 30 meters, but we'll see.  I actually have the transformer built, just still got some tweaking on it to get it right.  But so far I'm having trouble getting a good match with it and may just leave the Lmatch in place since I am able to work anyone I can hear on it.  Even worked Ocala Florida from my home in Southern Ohio on it with great signal reports !

 

KC8AON


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Re: 60 meter end fed half wave and an update
« Reply #1 on: January 20, 2016, 09:36:07 AM »
Nice report Lamewolf have any photos of the project including the build of the impedance matching device ?
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Lamewolf

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Re: 60 meter end fed half wave and an update
« Reply #2 on: January 20, 2016, 12:06:56 PM »
Nice report Lamewolf have any photos of the project including the build of the impedance matching device ?

Sorry, no pictures (battery in camera no longer holds its charge) but the ATU is just a simple L network consisting of an inductor in series with the coax and the antenna with a shunt variable capacitor on the output of the network to ground - standard hi z configuration.  If you go to google images and search L network schematics I'm sure you would see a bunch.  The antenna is just an 88 foot (1/2 wave on 60M) long wire attached to the output of the L network.  Nothing really fancy or special about it.