This is the design I followed ...
The vertical radiator was 585/14 = 41.8'
The radials were 246/14 = 17.6'
The matching transformer L1 122/14= 8.7' and L2 75/14 = 2.1'
Could have used the matching Q section instead of the Xfmer using 75/14 = 5.4'
The 5/8 GP has an impedance of 1600 ohms and the coax is 50 ohms so the calculations above are good to match the low impedance feed line with the higher impedance antenna... simple.
Getting the vertical radiator up 42' in a tree was a wee bit of a challenge with a 24' ladder. Cut down a skinny tall 24' poplar with a Y at the top. Dangled the counter weight over the Y part and ever so carefully raised the poplar from the top of the ladder to get over a branch that was about 43' above the ground! I think I could use this same method to go 50 or even 60 feet .... I have some very tall trees on my property.
The vertical radiator is about a #12 insulated copper wire. The base is a 1 ft chunk of 2X6 pressure treated. The vertical radiator is connected to the base with a large crew and washer . There are 4 Screws/Washers surrounding the center where the radial connect... get the picture! I will take a picture and post at some point!
The book that I took the design from seemed pretty reputable but I was a little bit leery of the matching transformer. Way way way back when I did understand the theory but I have forgotten far mar then what I know but I did recall this design so what the heck ... gave it a shot.
So how did it work .... fired it up at 14.1 Mhz and had a horrible VSWR 3.5:1 or there abouts ...figured I would be removing the transformer and cutting it down to a 1/4 Wave. Tuned up to 14.3 and the VSWR got worse , tuned down to 14 and it got better ... kept going and found that the antenna was very nicely tuned for 13.4 Mhz ...YIKEs. The original design was using a pipe as the vertical radiator and the GP was assumed to be a resonable ground. Whilest I was using some #12 wire and I have a lousy ground, its all about the radials!
So I started cutting and cutting and cutting. Results below...
Freq Initial -6" -6" -6" -6" -12" -12" -12" -12" -12"
13.3 1.4 1 1.7 2 2.2 3 3 3.1
13.4 1.2 1.2 1.4 1.6 2 2.4 2.6 3.1 3.1
13.5 1.3 1.2 1.15 1.3 1.5 1.9 2.3 2.9 3
13.6 1.6 1.4 1.2 1.1 1.2 1.5 1.9 2.1 2.6 3
13.8 2.5 2.2 1.9 1.6 1.35 1.1 1.15 1.4 1.6 2
13.9 2 1.7 1.3 1.1 1.1 1.3 1.5
14.0 2.6 2.1 1.6 1.35 1.1 0.5 1.15
14.1 2.6 2.1 1.6 1.35 1.1 1
14.2 2.1 1.6 1.35 1.15
14.3 2.5 2 1.6 1.4
Needless to say I took about 7' off the 43' vertical radiator ending up with a 36' vertical that was really really well tuned. Flat VSWR at 14.1 Mhz.
The California SSB QSO party was going on so I had a chance to work a few QSOs as seen below ...
So I was pretty happy with the antenna unfortunately I didn't get any signal reports working the Calif QSO party.
Being attached to a moving object I had to use a pulley and counter weight to keep the antenna in place. The counter weight I choose was a metal disc that was about 6 inches in diameter and weighed a pound or two. The way the disc worked out it was next to the top of the vertical radiator and it appears when I added the weight it affected the tuning as the optimal VSWR dropped a few Khz.
Next step is to get the ladder back out , drop the vertical element then replace the counter weight with a brick!
More to come!
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