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20, 40, 75/80, 160 and OCF80
The tower to the left is 73 feet of Rohn 25 and a Ham IV rotor with a heavy duty brake wedge is used to turn the array.
The Wilson 20 meter four element yagi is at the 74 foot level. Wilson always had issues with their gama matching system. Once I resolved the gama matching issue the array performed as expected. Measurement wise, this antenna is almost the same as the Hy Gain 204.
The Crushcraft 40 meter two element yagi is at the 83 foot level. By Crushcraft's design, they said to use coax coiled up for a balun. WRONG ! It did not work. I had to climb the mast, tilt the antenna and a friend of mine added a real balun to the feed point of the antenna. While he was attaching the balun, a bad rain storm came through and we had no choice but to complete the project in pouring down rain. That was probably the most dangerous time I even had on any tower.
A very interesting thing about the Cushcraft Shorty Forty, because of the coil placement, the antenna is actually resonant on 17 meters. I'd be afraid to run a KW on 17 meters into the antenna because of the wire size used to make the coils, but the antenna is in fact resonant on 17 meters. (On 17 meters the wire used to make the coils is too small to handle a KW. This antenna will handle 1500 watts on 40 meters SSB and CW.)
A half sloper for 160 meters is attached to the tower at the 72 foot level. It is really a great performing antenna and I would never want to be without it. Many years ago I made a half sloper for 75 meters. It was an outstanding antenna. Seeing the property size was too small for a full size 160 meter dipole, I decided to try a half sloper for 160 meters. It's been in service ever since.
A full size 80 meter Delta Loop, made by "Hy Power Antenna Company" is also on this tower. The apex is at the 72 foot level. I feed the Delta Loop in the bottom corner with a 75 ohm coax matching section. I modified this antenna. On the base wire of the antenna, about 89 feet away from the feed point, I have a tapped coil. With the coil bypassed, the loop is resonant around 3800 khz. By removing the jumper on the coil, the antenna is now resonant around 3530 khz. It takes me about 3 minutes to leave the primary station, change the tap on the coil and be back on the air. I am located 100 feet below average terrain and I was able to work VK's long path with this antenna. There is no question in my mind the Delta Loops are outstanding antennas.
80 Meter Delta Loop Loading Coil
I also use a true Off Center Fed 80 meter antenna. This antenna uses a 4 to 1 Guanella Current Balun (GU4 HF-5KW) at the feed point. By using this type of balun the transmission line DOES NOT radiate, I've checked for feed line radiation with an RF current probe on all bands and there was no sign of feed line radiation. This antenna is made by,"Hy Power Antenna Company". It is resonant on the following bands: 6, 10, 12, 17, 20, 40 and 80 meters. This is one of the best coaxial fed multi band antennas I've ever used. This link will show you the,"radiation patterns" of Off Center Fed antennas.
I just installed a low true Off Center Fed 40 meter antenna at the 36 foot level on this tower. I did this to do testing and liked it so much I have decided to keep it on the tower. I used a two position remote antenna switch to go from the OCF80 to the OCF40. On 20 meters I have found that in some directions the OCF40 to work much better. On 20 meters, where the null is on the OCF80, the peak is on the OCF40 and that has given me a 2 S unit or more improvement.
I use the word, "True' because so many hams call these antennas, "A Windom Antenna." They ARE NOT Windom antennas.
A true Windom antenna is a quarter wave vertical wire connected to a half wave horizontal wire which is attached one third of the way in from the end. It's kind of an off center fed top hat. This entire antenna is fed against a ground radial system. The feed point is at the bottom end of the vertical wire. One leg of the feeds is connected to the vertical wire and the other leg is connected to the ground radial wires.
10, 15, 30, 60 and 160 Meters The tower to the left is a Rohn HBX 56. It is 56 feet to the top of the tower with a mast making the total height of the tower 63 feet. Like on the bigger tower, a Ham IV is also used to turn the array.This is a free standing tower with 5 yards of concrete for a base. I dug the hole by hand and it was not a fun job.
At the 60 foot level is a dual band Wilson yagi. It has three full size elements on 10 meters and 4 full size elements on 15 meters. Just like the 20 meter Wilson, the gama matches on this array also did not work properly. Again I had to completely re do both gama matches on this yagi and it works great now. It is a dual feed array, one coax for 10 meters and one for 15 meters. It really works great into Japan.
The apex of a full size 30 meter Delta Loop is at the 45 foot level and is also fed with a 1/4 wave matching section of 75 ohm coax. The antenna is made by, "Hy Power Antenna Company" .
A 150 foot long 160 meter inverted vee dipole is tied to this tower with the apex at 55 feet. This antenna is also made by, "Hy Power Antenna Company" and is fed with a 1 : 1 Current Balun. For close in stations I’ve seen up to 4 S units advantage over the half sloper on the big tower. For DX contacts it can not compete with the half sloper. That’s not to say I can not work DX with it, it’s just the sloper does much better. This antenna is also resonant at 5.00 mhz so it can be used on the 60 meter band with great results.
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