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Posted: 10/11/2017 9:41:21 AM EDT
Planning to put up an inverted L for 160m. What wavelength you prefer 1/4, 3/8, what's your feed line, how many radials did you need, how you matching antenna?  

I can tune 160m on my 80m doublet, but as you would expect it's not good. Have worked 33 states on FT8 with it though, so I'm not complaining. Want to be ready for some winter time top band fun & maybe get WAS.

This antenna will be erected in a heavily wooded area so I may resort to elevated radials or just laying them on the ground.

Finally the $64 question, was the antenna worth the effort?
Link Posted: 10/11/2017 10:50:20 AM EDT
[#1]
Absolutely worth the effort, for me, anyways. I'm don't operate the radio more than a couple of hours a day, but when I do, my favorite activity is just rag chewing with the "locals", i.e. stations in the Northeast from say Ohio eastward, and North Carolina northward. 160 is an important band for that, and if you want to flex your AM muscles a little, too.

The nice thing about putting up an L is that you don't have to get all crazy about making it perfect. Just about anything will work. Sure, you can obsess about optimizing it, but it's not absolutely necessary. And, once you put it up, it can be a work in progress.

For example, mine is up all slapdash right now. The only thing I did "right" is hoist a pulley on an insulator into a 90ft tall pine tree. It's an elevated feed, up about 15ft at the eave of my house. The vertical element goes up at about a 20 degree angle to the tree, with about 70ft of wire to the pulley, and another 85ft of wire slopes back down to the ground at about a 45 or 50 degree angle, i.e. it's not even flat-topped yet. I've been too lazy to put another pulley into another tree. I just extended the wire with another insulator to some 550 cord and brought cord down to the ground and tied it off about 10ft up in handy tree. I put up two random length elevated radials. They are about 150 degrees apart.

I tried a 1:1 balun and that didn't work. I tried a 4:1 balun and that didn't work.  I tried no balun at all, just a plastic box I made with an SO239 mounted in it, and that worked great! Indeed, most of the L plans show no balun at all, just a choke (I use snap-on ferrites) and usually some sort of capacitive match. I don't have a match (yet), that's what tuners are for

Initially my wire length (14AWG THHN) was 125ft, i.e. a quarter wave on 160M. That worked, but I couldn't tune up on 80 or 60 or 40 very well, and I wanted this to be more versatile in case something ever happened to the dipole array. I added 30ft by splicing it on at the insulator with a wire nut, then adding another insulator at the end. 155ft did the trick, and now it tunes up well on 40 and below. I tried as much as 175ft, but it got worse again as I made it longer.

I really should have my tuner at the feedpoint, and it is a nice remote tuner, an MFJ-998RT, but I use if for both my dipole array and the L, so it lives at the dipole feedpoint and there's 50ft of RG-8U that goes to the L feedpoint.

Performance-wise, on TX it is great. I get good signal reports from everyone on 40 and below. I couldn't run 160M before, the 80M dipole element would only allow 300W or so, and absolutely no AM, as the standing waves on the dipole ladder line were so bad (voltages high) that the balun would saturate. But now I can run any power I want and AM on 160M and that made me very happy. On RX I am less happy with it. It is a VERY noisy antenna as currently configured. I work around that by using the dipole on receive and the L on transmit.

So, again, I am happy with it, and it is a work in progress. I need to clean up the plastic box at the feedpoint and attach it to the house properly. I need to get the other end in a tall tree. I need to add another radial or two and optimized their lengths. And I really need to put the tuner at the feedpoint. I figure in another two or three years I'll be done with it. That's how long it took me to evolve my dipole array, why should this antenna be any different

After that, maybe I'll put out some nice beverage antennas for 160M receive. That's what all the big boy 160M DX'ers do: L's on TX, and beverages on RX.
Link Posted: 10/11/2017 11:20:06 AM EDT
[#2]
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Quoted:

After that, maybe I'll put out some nice beverage antennas for 160M receive. That's what all the big boy 160M DX'ers do: L's on TX, and beverages on RX.
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I want to be "that guy " who uses a small tuned loop for both
Link Posted: 10/11/2017 11:25:28 AM EDT
[#3]
Good info. The L will most likely be noisy on receive for sure, but I can listen on the 80m doublet if needed. I've heard several DX stations on the doublet, but no way for me to put out a signal they would catch. I have to place antenna in a hardwood stand. That pretty much describes WV, hardwoods & hills.

I will need about 125' of feed line, but on the low bands losses shouldn't be much. I will use shack tuner to touch it up & see what some other bands look like, but my primary use will be 160m.  I do have a large lawn, but no way I can get away with stringing beverage antennas.

Question: The antenna is grounded at far end feed point & the coax shield will also ground at my bulkhead entry. Any problems with that?
Link Posted: 10/11/2017 12:14:33 PM EDT
[#4]
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Quoted:
Good info. The L will most likely be noisy on receive for sure, but I can listen on the 80m doublet if needed.
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Quoted:
Good info. The L will most likely be noisy on receive for sure, but I can listen on the 80m doublet if needed.
That's exactly what I do. It's easy on my Apache Labs rig, I just set it up to TX on ANT1 and RX on ANT2. I manually repatch when I go to 40M and above. That should work very well for you. (BTW, my next project is an antenna switch for this, but more on that in another thread...)

I do have a large lawn, but no way I can get away with stringing beverage antennas.
I just looked you up on the zed, and you are in a perfect place for stringing beverage antennas. All of those beautiful woods behind your house! I have exactly the same setup. You just bring a step stool, a screw gun and a bag of electric fence insulators out there. Screw them up about 10ft off the ground so that you and the deer don't clothesline themselves. Put one up NE/SW, the other at right angles, have them meet at the woodline where they go into one of those fancy DX Engineering beverage controller boxes. They don't have to be perfectly straight, or even perfectly level. A little direct bury RG6 back to the house, along with the sprinkler wire for power and control, and Bob's your uncle! Oh, sure, I make it sound so easy, and I haven't done it either , but it's not for lack of room to do it!

Question: The antenna is grounded at far end feed point & the coax shield will also ground at my bulkhead entry. Any problems with that?
My coax shield and radials are not grounded at the far end, but they are at the tuner end. I haven't tried grounding it at the far end yet. That might make a difference. I do have an easily accessible ground at that end, I just haven't played with it yet. It might quiet it down, and it might make it worse. We'll see!
Link Posted: 10/11/2017 1:30:08 PM EDT
[#5]
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Quoted:

I just looked you up on the zed, and you are in a perfect place for stringing beverage antennas. All of those beautiful woods behind your house! I have exactly the same setup.
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I forgot about using Google map to view property layout, duh. That is an older picture. Shows where it's brown before the grass grew on septic leach field. You can see that large tree in front of house holds up the 80m doublet. The L would go behind in the wooded area. Hmm, may have to see about a beverage set up after I get L up. For sure would have to be above deer & critter level or it wouldn't last long around here. I'm going to give it a shot soon, for good or bad.
Link Posted: 10/11/2017 2:03:35 PM EDT
[#6]
Mine is off the top of a modified Hustler 6-BTV, with the 80m resonator removed & replaced with a coax coil 40m trap (I get full 80m band via another "L" off the hustler feed point). The wire is belayed about 10' above the hustler & then a pretty shallow angle to the tree pull point.  The hustler has 42 radials (?), mostly near field (~30')  with the 6 longest 60' each.  It does pretty well on 160m, but most of my normal use is fairly close in (< 350 mile radius) & the ladder fed 160m FWL typically does as well or better.  The "L" may have a DX advantage, but haven't pursued that.

Nick
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