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w3bny
03-14-2010, 09:07 PM
Hiya folks. It's been an icky weekend but I was able to get some stuff done on my vertical. Not what I wanted to do (dig a trench, lay some conduit and run coax/control cables) but today was able to get something done.

For those of you who dont know what I am up to, I took on building the AD5X 43' vertical 10/80M matching project as seen in the December/January issue of QST magazine (if you don't get QST, go to http://www.ad5x.com/images/Articles/Match160.pdf for all the details!) .

Since it was so darn icky and I wasn't able to lay conduit or lay out radials, I decided to mount the box. I binked some pressure treat as verticals down with 1x2 cross braces. (I was going to dig a hole...but it was moosh so I took out my binker to whack them into the ground. Here is the overall view of the box as mounted and connected.

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/installedbox.jpg

As you can see, I decided to forgo the usual wiring convention and go off the deep end with 2" copper straps. No, they are not from Georgia Copper, I made them! I started off with some copper flashing that I had gotten from Dyson's (a local mom-pop hardware store) a while back. Took my handy-dandy IR pneumatic sheers and WHRRRRRRRR I now have a 2" strap as long as I need them. So, why copper straps instead of wire or braid? Simple. Copper strap provided a greater surface area then wire. And since we are dealing with RF and the surface effect (RF tends to hang out on the surface of cables) so I gave the RF a larger surface to travel along and provide a lower impedance for the RF to travel on vice the braid or 2Kv wire that I may have used. (side note: I changed out the braid that I was using on my SGC-237 coupler on my truck for a 2" wide copper strap. ZOMG!!! Big difference! Coupler takes oh...about a second or less to tune up on all frequencies above 80m. 80 is still a bit persnickety...but hey..Im trying to load up a way short antenna on 80! But it still loads!) Here is a side view of the box.

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/sideview.jpg

Now...why is that copper so pretty looking...Blame the Navy and its 20yrs of programming (if its copper or brass...ITS POLISHED) Its not a mirror finish but its clean. And I expect it to stay that way for oh....10 years or so. How you ask...HEH...."Ancient Chinese Secret" (First person to tell me where that line came from...I owe you a soda at the least!) Actually its from a certain coating called PERMALAC. I saw it on an antenna page and was impressed with its properties (copper protection and general UV protection). Be advised though. THIS STUFF AINT CHEEP! A spray can is 21 bucks and 10 bucks for shipping! You don't want to know what a gallon of the stuff costs...so use it sparingly! Want more info? http://www.permalac.com/ So the bulk of it is permalac'd...except for the connection points. They are clean copper...albeit with a coating of conductive copper laden grease (got it from ICE suppressor folks). Here is the side view of the connections...

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/boxmounts01.jpg

And here is another connection point view with a gross view of the connection to the DX engineering radial plate

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/boxmounts.jpg

Here is the connection to the antenna itself.

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/antennamount.jpg

Here is a close up of the mating to the radial plate. I left...2 inches un-protected and I coated it top and bottom with conductive copper grease.
And mounted it on four points with star washers (top and bottom) stainless steel 1/4-20's and flats/locks. Yeah its over kill but you cant tell me that there isn't enough surface area mating the copper to the radial plate!

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/radialplatemount.jpg

And here is the box and antenna...as seen from the side.

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/fullview.jpg

And that's what I did today. I probably wont lay conduit or radials next Saturday (Church stuff) but will probably do something Sunday.

If you guys have any questions please...feel free to ask. Otherwise...

Thanks for letting me take up your Sunday evening.

P.S. IOU pics of the inside of the box.

ka8ncr
03-14-2010, 09:20 PM
That's some fine professional looking work.

When I was much younger and hanging around AM stations, we never worried too much about the look of the copper. We did apply a weatherproofing monkey snot over connections that were not soldered, but I have to admit the shiny copper looks quite nice and tidy.

What are you going to use to slit the earth for the radials? I found a used electric chainsaw at a garage sale, found it to work like a champ for radials.

KG4CGC
03-14-2010, 09:25 PM
Nice project and chainsaw FTW!

KC9ECI
03-14-2010, 09:39 PM
Calgon. You owe me a soda Bunbun, but I'll take a beer or a Scotch. I'll be at Dayton 2011.

N8YX
03-15-2010, 06:13 AM
Calgon. You owe me a soda Bunbun, but I'll take a beer or a Scotch. I'll be at Dayton 2011.
Not making the trip this year, Tom?

PA5COR
03-15-2010, 07:05 AM
The time and preparation put in the antenna system will be well invested m8.

Better do it good the first time, my 160 and 40 meter vertical now has about 1000 feet of copper wire as counterpoise.
Running everywhere i saw chance to put a wire away in any form or shape.
Mind you we have good soil here, always wet and conductive.

Mine is 45 feet high, fed at the base and partly helically wound and a T of 2 x 40 feet wires on top as C.

I connected everything i could find of metal to the ground system, the house ground, the satellite mast, ( dug in 8 feet in the ground) etc.

A 100K pressed carbon resistor between radiator and ground takes care of the static charges.
I can run 1 KW in it with no problems here with people's gear, as i can do on the other 2 H.F. antenna's.
I think this summer i'll try a T400-2 torroid, 1:4 UnUn transformer and a autotuner directly at the base.
Fed directly it is resonant at a wide area round 1850 and also does well on 40 meters.
The rest of the bands sucks... :roll: , then i build it originally for 160 only... ;)

Good luck with the radials, nice piccies and set up though ;)

w3bny
03-15-2010, 08:14 AM
Calgon. You owe me a soda Bunbun, but I'll take a beer or a Scotch. I'll be at Dayton 2011.

WINNER! And dont expect that top shelf stuff... Its class 2/NEX scotch for you!

Radials...yeeah.... I have ripped up the old crap that I thought was a radial field (about 500') and have 60 43' radials ready to be installed. BTW...that's 2,580' of #14 ready to be laid down. And each mounting point crimped AND soldered thank you very much.

As for laying them or burying them. PEH!! surface mount and landscaping pins. Thats why I have to work quickly. I have to get them down before the "lawn" (cultivated weeds more like) wakes up. Once they are down the grass weaves over them and you will never know they are there. And let me tell you...they were a beehatch to get up!

I wish I could elevate them up a foot but alas...I do like going out back every now and then.

More later!

PA5COR
03-15-2010, 10:04 AM
Don't use normal solder, it will turn to white powder within a few years :oops:

Cadweld, silversolder etc, and even then protect the weld.

Paved my backyard, so all the radials are under the pavement, 2 " below the pavement.
Front garden, used your method, just let the grass grow over it.
The rest of the garden, used old large metal saw blade, "scratched a small v 2" deep, wire with pegs in it, use size 13.5 shoes and 250 pound body weight, done.
:rofl:
In total 12 rods 10 feet long are the safety ground, less as 0.14 ohm ground resistance measured by the electricity tech, also part of the .radial field.
Our scrap metal firm had some nice old copper which i bought for scrap metal price, and a large cake.
Never saw someone so surprised and doubting his expensive megger, till i told him why i had such low value.
Soil here is young silty seaclay. ( this was part of the sea till 1810....)
All copper wires are bare, 3.2 mm thick.
8)

;)

w3bny
03-15-2010, 10:10 AM
Don't use normal solder, it will turn to white powder within a few years :oops:

Cadweld, silversolder etc, and even then protect the weld.

Paved my backyard, so all the radials are under the pavement, 2 " below the pavement.
Front garden, used your method, just let the grass grow over it.
The rest of the garden, used old large metal saw blade, "scratched a small v 2" deep, wire with pegs in it, use size 13.5 shoes and 250 pound body weight, done.
:rofl:

;)

Now you tell me. Too darn late now. wait....hmm.. permalac and adhesive heat shrink? dunno. Now Im going ot be loosing sleep over this.

N5RLR
03-15-2010, 01:37 PM
Excellent work, Ren. :agree:


Don't use normal solder, it will turn to white powder within a few years :oops:

Cadweld, silversolder etc, and even then protect the weld.
Now you tell me. Too darn late now. Wait....hmm. Permalac and adhesive heat shrink? Dunno. Now I'm going to be loosing sleep over this.
Eh, make as clean & tight a connection as possible, weatherproof it as best as possible, then keep an eye on it. No problem.

KC9ECI
03-15-2010, 03:02 PM
YX-

Nope. Flying out to the UK the week following and it would have just been too much to do both this year both in time and cash.

Bunbun-
No problem, as long as it increases my BAC and I don't go blind or wake up in a bathtub full of ice and missing a kidney or a testicle I'm good to go.

N5RLR
03-15-2010, 07:29 PM
A 100K pressed carbon resistor between radiator and ground takes care of the static charges.
I can run 1 KW in it with no problems here...
*ack* I overlooked this earlier. What wattage value on the resistor, Cor?

N8YX
03-15-2010, 08:13 PM
A 100K pressed carbon resistor between radiator and ground takes care of the static charges.
I can run 1 KW in it with no problems here...
*ack* I overlooked this earlier. What wattage value on the resistor, Cor?
I used a 2.5mH RF choke between each of my vertical's feed points and ground. Works good; does the same thing. Encapsulate them in a piece of PVC pipe with end caps which are drilled to take a 1/8" x 3/4"L bolt. A pair of ring terminals - one on each of the choke leads - provide connectivity to the bolts; they're passed through the terminals and out of the caps. Anchor the hardware in place with a flat washer, lock washer and nut. Another set of ring terminals/wires and washers/nuts slipped over the remainder of the bolts allows you to connect the choke to the antenna feedpoint and ground.

PA5COR
03-16-2010, 03:27 AM
Running max 1000 watts i had a 5 watt resistor, a 2 watt would have been fine too.

100 K over 50 Ohm, do the math ;) , use anything between 10k to 100k whatever you have, with 10k i would look for a 5 watt type, use pressed carbon, not the resistors that have their body shaped as a coil.
As kid i saved a lot of these resistors from tube amps, telly sets etc, they now are hard to come by here.
Helped out lots of hams with them.
God i feel old now... :roll:

:rofl:

w3bny
03-16-2010, 07:43 AM
The box has a transplanted I.C.E single wire supressor build in. http://www.iceradioproducts.com/impulse1.html#2

Still owe you all pictures of the interior build.

PA5COR
03-16-2010, 08:26 AM
Quote
Still owe you all pictures of the interior build

We can wait ( not too long please)
;)

w3bny
03-16-2010, 06:51 PM
As promised... here are the gizzards.

1. The outside. Normal 10x12x4 NEMA box but I decided that I wanted to see when the relays kick over so installed a dual color led so I can look out the basement window to verify operation. oooh pretty lights!

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/Gizzards01.jpg

2. Open lid. Nothing special. Just a connector block and ballast resistor. unscrew the terminal block and totally remove the lid.

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/Gizzards02.jpg

3. GIZZARDS! 4:1 Balun, relays, circuit board, main inductor and output section

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/Gizzards03.jpg

4. Input section. I used Amphenol RF connectors! Oh and the copper tape...from a guitar repair company! you get three sizes for like 20 bucks. The input 4:1 is from MFJ. Yeah I could have ordered all the junk from Amidon...but peh! just buy it and be done with it. Still had to integrate it so some brizain work is envolved. :wall:

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/Gizzards04.jpg

5. Control circuit section. Easy circuit. Built on radidio shellackikus bread board. All the bus wire underneath is conformal coated...of sorts.. hawt melt gloo baby!

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/Gizzards05.jpg

6. The RF Relays. They are actually Deltrol control relays. But they are ganged together to help with the high voltages that may exist with legal power. Notice the pretty white wires? 12ga 2Kv wire baby! (Surplus Sales of Nebraskee)

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/Gizzards06.jpg

7. Inductor. Yeah...MFJ....you think Im gonna wind that beast...HAH! Why walk when you can ride! Anyhow the taps are loose and will be finally adjusted when the radials go down and the coax is pulled.

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/Gizzards07.jpg

8. RF output section. Neat looking eh? I cant take credit for it. I bought a ICE single wire suppressor and pulled it out of the carlon box and integrated it into my box. Two birds with one stone! dont have to worry about where to mount the suppressor. Its in the box and continuously draining static (Thanks to senior Coulomb and his silly laws!). Notice all the swanky ceramic bits! About a year or so ago bid on 20lbs of ceramic goodies on fleabay... Guess who won! Lulzy box of junk. a bunch of it was crap but the most part was good ceramic once I cleaned it up (two day Sodium Hydroxide soak :twisted: )

http://i20.photobucket.com/albums/b220/Bunnieman/W3BNY%20vertical%20antenna%20upgrade/Gizzards08.jpg

Anyhow...thats it. Im not describing the T.O.O. You can read the same as I can from AD5X's site.

Questions? Ask away! More later from BNY labs...

http://i20.photobucket.com/albums/b220/Bunnieman/beafraid_1024x768_2.jpg

PA5COR
03-17-2010, 03:27 AM
WOW 8)
Love the details, and the labelling of the stuff inside ;)

I had the 1:4 UnUn homebrew on the vertical i made before the current one.
Then i only run max 1100 watts into my stuff...mostly much less.

Doing it right the first time will pay off.
You have the same idea's as me, i also like to over engineer my stuff.. :roll:
I'm very interested in the results using the antenna, please keep us updated 8)

If you get the radial field right it should suit you well and give good results.

Again, well done, my compliments!

Cor