80 Meters Was out of Reach…
I have a pal who lives a stone’s throw away from me. He kept telling me about a group that he chatted with most nights on 80 meters. The closest I could get was 40 meters with my multiband inverted vee. I could hear those guys clear as anything, all 300 miles away. Try as I might, my 40, which tuned for 80 just couldn’t make the trip with my barefoot 100 watts.
It took me a while to figure out how to get such a long antenna in my rented back yard. I did a lot of measuring and drawing in Autocad to make absolutely sure I could put this up back there. When I was finally convinced, I told my pal Lloyd, that I was going to do it. I told him I’d get it as soon as I ordered and received some more wire. Being the great guy he is, he told me he had wire for me to just come and get it. I was more than appreciative.
Wire in hand, I knew I’d need a balun to bring it in from my 450 ohm line that I would use from the feed point to near my window. I ventured onto the Internet and found an outdoor electronic project box. It was about 3.5×5. Perfect for the toroids I had already purchased. Parts in hand, I began work.
That is 12 gauge stranded copper wire that I’ll use to make a 4:1 balun. First time ever for me.
The first step, was to secure two of the toroids together. Duck brand duct tape provide the necessary security.
Here I go, winding all that wire around the green and silver doughnut.
Admittedly, I could have used some more pliable wire. This was pretty stiff and wasn’t the easiest to wrap.
Eight wraps later…
My fingers were sore after that. I next had to make sure that would fit into my project box.
Indeed it did, barely. Next I needed to secure the necessary attachment points for the 450 wire as well as the SO-239.
I opted to have the box hang along its tall side. This gave the top and bottom the smallest surface area for rain.
Naturally, I didn’t have the large size 5/8 drill bit, so after using this ½ inch one, I hogged out the hole…
Well, that’s not so pretty, but it is effective. Large enough to accommodate the SO-239, small enough to allow the hardware plenty of bite.
Now for the hardware…
The loop to hang the box, the wingnuts and bolts for attaching the 450 line.
But first, weather sealing for the SO-239.
I had this rubber sheet laying on my desk for weeks or months. I forget what I actually had it for. I thought this might be an opportunity to make use of it.
I cut out the square about the size of the frame of the connector. I located the center and poked a hold. Then used scissors to cut a circle out, that I had pressed in, using the connector.
Behold! It fits. It is a very snug fit. But that is what I was looking for. Hardware placement was simple after that.
All snug fits for all. You can see the undersized drill bit laying there, with evidence on it.
Once I had that, I placed it into the hole I created in the project box.
The cupping you see, was perfect when I tightened everything down.
Here only three nuts are applied. The fourth will be the attachment point for one of the wires from the balun.
Now it is time for the bolts to bring this thing to life.
That was easy.
I decided to use faucet rubber washers to waterproof the bolted areas. The size was nearly perfect.
Here it is, pretty much done, but not pretty. (My desk is a mess too.) I soldered loops into the wires before attaching them around the bolts and nuts.
Before I put the lid on, I made sure to do a continuity check of all connections. Worked like a charm.
Next up, the wire and wire and cutting board…
Yes, this is a plastic cutting board that I re-purposed for that 6 meter beam I created a few months ago. It was perfect for use here.
I used self-tapping bolts to attach the 450 line to this. I stripped the 450 back to allow enough to butterfly it so I could use more of the self-tapping bolts right in the plastic to hold the line up.
I didn’t photo the cutting of the elements, as many of you probably know how to measure and cut. (Not that you didn’t know how to do what I am describing.) I stripped the ends of the elements and soldered them into loops around those self-tapping bolts. The lower ends are attached to plastic isolators from the local farm store. I picked up a couple of the T-posts used for fencing to attach the bottom. The antenna (cutting board) is raised with 550 cord I got from the military surplus store. It goes to a pulley I placed at the top and works the same as the multiband on the opposite side of the pole.
I have a tee at the top of the pole and some pipe that sticks out. I used that to my advantage and placed some zip ties to keep the 450 line nearly vertical for about 24 feet. You can also see all that mess of multi-band wire hanging from the other side. That has been replaced. (Story coming soon.) The other lines are more 550 cord is used for guys. So far so good.
On the other side, I have the balun hanging about 3 feet from my window. It hangs on the guy chain from my TV/6 Meter/2 & 70 mast. A short piece of coax runs to the window, then another short piece to the antenna switch inside.
All connected, I ran inside and tuned it up. Worked great. Unfortunately, I couldn’t get on the air that night since I needed to get to bed.
The next evening, I hopped on there and tried to get in on the group QSO. My rig and tuner cried in pain immediately. So I ceased transmission after my KK. I tried to tune and it wouldn’t do it. I was at a loss. I hit up Loyd and asked what he thought. He said, likely water from the rain we had that day.
I wandered outside and expected to take off the PL-259 and dump water out. I didn’t even need to take that connector off. As soon as I looked at that balun, I saw it. One of the bolts were in solid contact with the guy chain. Went straight to ground. I rectified that problem and went back inside, tuned like a champ.
So, now, even just a few minutes ago, I finally got to get in with those great guys on 80 meters.
Unfortunately I can not place a 80-meter antenna, too little space.
73 Ben PA2OLD – the Netherlands
Good story but how did you make a 4:1 balun with only a single bifilar winding? Don’t think that is possible. The pictures suggest a 1:1 balun/choke.
I am also space limited. I can put up an antenna for 40M easily but that’s about it. However, I can get on any frequency from 160M to 10M and also use 6M but only when the band is open to my location. For me, it is easy. Interested? Keep reading…
I lived overseas for many years and when I returned, the old-time ham friend who gave me my Novice exam about 1970 gave me an antenna he had, a second one that was the same that he had put up. It was a Barker & Williamson TTFD which is a tilted folded dipole. I do not tilt mine, though. I found it is not necessary. I have since then acquired three others but sold one and gave one to my son in CA who thought it was defective on field day when he first used it because it was so quiet. First contact he had was a station in Japan.
There are naysayers who smugly call the antenna an “air-cooled folded dipole” and snigger and grin whenever the antenna is mentioned. Invariably, though, they have never put one up and used it. Therefore, I speak from experience.
I put up a G5RV Jr. and it outperformed the TTFD on 40 and 20 Meters but it was also in a better orientation and higher. However, the TTFD is less than 3:1 SWR worst case and requires no tuning — anywhere I tune it. Mine is 90-ft long but for 40M and up, cutting it to half size should still give you 80M and up. The TTFD is a 600 ohm antenna which means the balun at the feedpoint is a 12:1 ratio. Some have made them with a 9:1 and other ratios and also have similar results. However, the one I have is the traditional design and works well.
The B&W TTFD is relatively expensive. One can go to other sources and buy the balun and even the terminating resistor and save much money. Mine uses simple PVC separators cut to 18-in long, three to a side with the one at the end being tied to Dacron rope. But the termination for 100W may be made up with a combination of non-inductive resistors with a power rating of about 25-30W and work very well.
The TTFD is not the best antenna in all worlds. It is a compromise antenna in some ways but it is a quiet antenna (signals can be heard and not covered up with noise), it is easy to tune (no tuner is necessary, in most cases), and it is small comparing with antennas that may be more efficient but are designed for a limited number of bands.
I have found the B&W TTFD on the QTH Swap Page for about $125 — a bargain…
Here is more info on the antenna, along with the history and formulas:
Here is the main page on the TTFD:
RE the comment about the 4:1 balun a single bifilar winding, keep in mind that if you feed one of the windings with the transmitter but connect the other winding as if in series with the fed winding, then the voltage is doubled, theoretically, but the impedance is calculated at the power of two. Therefore, the square of 2 is 4 which means it is a 1 to 4 ratio, impedance-wise.
I make 4:1 and 9:1 baluns all the time but wind them on PVC. They are relatively broadbanded and work very well. The 9:1 is trifilar wound with the three windings in series. One of the windings is fed while the output is taken from the overall, combined windings. To make it work, you have to take the end of one winding and bring it back to the beginning of the next winding to keep the signals all in phase.
There is an interesting antenna using this principle that may be of interest. It explains the principle and gives details. Keep in mind that the dot on coil windings indicate the start of the winding.
An end-fed dipole in kit form can be obtained from [email protected] for about $35 and is relatively easy to put together. More info is here: