The Defpom Forum, for RadioMods, S&M Software and Music by The Defpom

I put this together in about 4 hours because I wanted to see what results could be had from such a thing. First time up the SWR on 40 is 1.4:1 and on ch1 it is 1.9:1. Talked and receives just fine. More later. Gotta go back to work.



All the weird curves is my camera doing strange things again? ? ? :cyclopsani:




Materials for Quick AP:



The bottom ring assembly:



Coming together:



More tomorrow.

Spec sheet with measurements available on request. Too big to post, if reduced unreadable.

Worked on it little more. I had the top bracket too wide, so I replaced it with sturdier aluminum stock (second u-clamp wasn't on it yet in the photo), and adjusted the width a little more at the mid bracket. SWR is closer now - on ch40 1.2:1 and on ch1 1.4:1.

Getting there. I probably won't make this a keeper, just a for funner. I'll likely let it go to a friend for cost of parts. Just a little more . . .

A little more tinkering done. SWR 1.1:1 at 40 and 1.

Some contacts a few minutes ago with bottom ring mounted 20' in the air.

3030 --------------------------------- 26.695 AM NC
7440 --------------------------------- 27.385 LSB
WR077 ------------------------------ 27.385 LSB GA
206 ---------------------------------- 27.385 LSB TN
619 ---------------------------------- 27.385 LSB KY
662 ---------------------------------- 27.385 LSB Lake Erie
Rusty Nail ------------------------- 27.125 AM

Others I didn't write down.

One of my purposes in making this AP was to show that an antenna can be done on a very tight budget that performs admirably well. Everything on this antenna was purchased at Home Depot. Some things, like the roll of tape, and the aluminum flat stock, cost more than the figures to purchase, but the cost is prorated to reflect the amount of each that went into the project. While i might would replace the tubing with aluminum tubing if I wanted maximum durability over the long haul, that in no way means that this homebrew AP is taking a backseat to any other antenna performance-wise for those who need a budget product.

cost of materials:

top hat rods ----------------- 4.00
aluminum plate ------------ 3.50
u-bolts ------------------------ 5.00
screws ----------------------- 0.75
PEX tube --------------------- 2.50
CPVC tubes ----------------- 4.65
CPVC tees ------------------- 2.00
Aluminum tape ------------- 2.00
3/8"x4' fb rod ----------------- 1.00
________________________
total ---------------------------- 25.40

The center mast pipe is what ever mast you use. I already had it and the fellow who gets this antenna will get his own or pay me to replace the pipe i have.

Set up outside under my umbrella (too #&*#$^@%$ hot otherwise) I put the MFJ209 and the frequency counter in line and this is what it says.

2.0:1 ------------------------ 29.695
1.0:1 ------------------------ 27.875
1.1:1 ------------------------ 27.405
1.2:1 ------------------------ 27.205
1.5:1 ------------------------ 26.695
2.0:1 ------------------------ 26.415

The setup testing:

Readjusted some things, tightened up some joints, recalibrated measurements, changed out the center spreader for plexiglass plate, and beefed up the clamp on the longest leg to the top plate. I think it has a little more symmetry.

Got it above the Yagi for a workout.

To the tip-top it is 57'
To the coax connection it is 53'
To the bottom ring it is 45.5'

I have the Homebrew Astroplane back up temporarily as I do repairs and upgrades to the tip-over tower. The SWR is still great, and it works a charm.

aloha from HAWAII. joined this site just cuz of ant, build. shipping is almost same as cost of ant. from mainland. got lowes and home depot here. sure parts cost more but still better deal. would really like to have blueprints to build one. 73's and a big mahalo (thanks). kula guy

Welcome to the site, kulaguy, and thanks for your interest in the antenna.
Building and using homebrew antennas is the best part of the radio hobby for me. I do it for the pleasure I get from it, but sometimes I also save money. There are several antennas I have built and are now flying over someone's shack in my area simply because I was done with them and they needed to get on the air.

In the photos below you'll notice dimensions are metric. Some of the more critical dimensions I've converted to US Imperial decimal measurements, such as 320 metric to 12.6 (or 12 5/8") Imperial. There is a metric converter at this location for those I didn't convert:

http://www.worldwidemetric.com/measurements.html

Have fun, and ask any questions you have. I'll try to answer them.