One - Do- Tree... Tests with the 2x2x2 40M Yagi stack

[WA1GFZ]

Boom is built ropes are strung. Hopefully Sunday I'll suck in the gut, strap on the belt and haul it up. Got stuck in a parade during 1 trip to the hardware store. Then I run into a high school pal I have not seen in 15 years. Just got home from football. My turn to help load stuff and put it away. I had to be very careful not to stress the back.

I agree Tom, don't mess with success. You can fill in western EU with mr ugly.

[w3jn]

The delta loops are working FB, Tom.  It's almost 8AM here in SV and yer still S-9.  Before sunrise you were stronger than the Italians - and that's quite a message!  Now I can't hear most of the EURs at all.

[Steve - WB3HUZ]

Tom ran everyone off the band. Even his old DX homies couldn't keep up with him and gave up. WHIRL WIDE!

[K1JJ]

The delta loops are working FB, Tom.  It's almost 8AM here in SV and yer still S-9.  Before sunrise you were stronger than the Italians - and that's quite a message!  Now I can't hear most of the EURs at all.

Hey, that's cool, Johnny!  Not bad for you to hear that well on 75M with the short wire. Yep, figured we'd give 75M a try for the first time in many months. That was the first trial of the new pair of delta loops at 190'.  It has switching NE or SW and the front to back reports came in at 20-30db. So I'm happy.

I thought maybe 75M was dying out cuz of 40M activity, but later in the night (11:30 PM local)  the Euro pileup grew so thick and deep I had trouble pulling out a letter sometimes. I'm still recovering after holding court continuosly for about 4 hours last night. Gawd, it was fun! There was latent demand built up like a sewer pipe I guess. I took out my screwdriver and unplugged that little hole in the bowl and all hell broke loose...

I'm still amazed at the HUZman's hearing ability - this time on 75M.  He was hearing better than two big guns up here in the Northeast. They took off after passing on a few stations, while the Huzman hung in there and continued to give out reports. I'm cornvinced it's his FB VA location with the lake and swamp to the northeast  towards Europe. His bevs help and he expects to get up a phased array on 75M of some kind. The locals are gonna be in for trouble up here...

[Steve - WB3HUZ]

I took a look at my Beverages today as I was making some final connections and sealing up the coax fittings. One of the bevs was unterminated! It wasn't the other day when I checked. I probably could have heard much better. I was wondering why there wasn't much difference between the dipole and the bevs last night. 

[Steve - WB3HUZ]

Here's Tom strapping in Saudi Arabia on 40 meters.

http://www.amwindow.org/misc/av/K1JJ-Saudia%20Arabia%202009-09-20%20031355.mp3

[K1JJ]

Here's Tom strapping in Saudi Arabia on 40 meters.

http://www.amwindow.org/misc/av/K1JJ-Saudia%20Arabia%202009-09-20%20031355.mp3

Heheh... thanks for uploading it, Steve.

Yep, Abdul/7Z1CQ  sent that along last night. It's interesting to hear what it sounded like in Saudi Arabia.  Abdul appears to have a good recording system.  I notice the signal to noise was MUCH better on this recording than the other two videos from Turkey.  There's virtually no static in the background. Yesterday, when this recording was made on 40M, it was a very low angle night - and it shows in s/n.


T

[K1JJ]

Here's some pics of Frank / WA1GFZ's new boom for his 40M wire array.  Notice the nice job he did on overhead trussing, pulleys and the boom to tower brackets.

This will keep a pair of inverted vee dipoles or delta loops high in the air, off the ends of the boom. This is a clean way to get a strong support for all kinds of experiments. Notice he can raise and lower the elements from the ground, once installed.

This is today's work, so we expect some antennas up next week.

T

[WA1GFZ]

I'll be back on 40 in a couple days after I retune the feeder system. The bees got very unhappy with me at 55 feet and started landing on me so I bolted the boom at 55 feet. It isn't 3 duces but will get me on. New configuration let me remove 80 feet of coax from 1 run so everything needs to be adjusted. Also carefully measured the feed line lengths so I don't have to guess. I didn't put baluns on the feed lines yet. All my rigging stuff is at GFZ south so had to carry the boom up the tower what a work out.
Huz how far apart are your  RX antennas

[WA1GFZ]

Notice my size 12 sh1t kickers wedged into the tower around the Log drive shaft.
Rohn 25 is the biggest tower mistake I made 30 years ago to save  about $200

[K1JJ]

More WA1GFZ Boom Pics:

Notice the competition is getting nervous....

[Steve - WB3HUZ]

They are spaced 20 feet and staggered 25 feet.

Huz how far apart are your  RX antennas

[WA1GFZ]

Wow 20 feet is close. I wonder what happens at even closer spacing?
Thinking parallel plate type antenna.

[Steve - WB3HUZ]

Not for beverages. No coupling at all. They are lossy and non-resonant. Some people space them only 10 feet.

[WA1GFZ]

Do you use 1 feed line and a load at each far end?

[W9GT]

Frank,

Nice boom installation on the tower!  I need to do something similar to support two diamond shaped full wave loops, but wanted to hoist the whole thing up the tower with a pulley and rope.  My initial attempt to use a lighter structure using PVC pipe was just too flimsy (even with support ropes).  Guess I will use some 3" aluminum tube and try to get some help to get it up on the tower at the 72' level.  I just don't like to climb much any more.  My tower is 38" across the face and I climb up the inside of it, so at least that helps.  Even my single loop works great on 40, so two should work really well.  I plan to try some different feed arrangements and see which works best.

73,  Jack, W9GT

[WA1GFZ]

Jack 2 inch 1/8 wall will be fine if you use the guy cable truss. I'm glad Tom talked me into it. I used 1/4 inch guy wire. I was surprised how easily I could bend the tubing once it was bolted to the tower. I think you could stand on it now. I would have pulled it up with a rope and pulley if rigging wasn't 60 miles away and I just belw my wad on SS hardware. I sure got a work out lugging it one step at a time.
I double nutted everything and the clamps are not cheap. Also used lock nuts as the second nut at the boom ends. 38 inches on a side, I don't feel sorry for you unless you wear bozo the clown shoes.  I have a number of different configurations to simulate but will start with dipoles. I saw some nice FB with it hanging from ropes.

[Steve - WB3HUZ]

The back beverage is fed through a 180 degree phasing transformer and a 34 degree phasing line. This connects to a combiner with forward beverage. From the combiner, there is one coax back to the shack. The cool thing is that the phasing tracks over multiple bands.

This phasing arrangement is an old technique, although newly discovered in the amateur radio ranks. I used directive arrays by a commercial manufacturer back in the 1980s using this phasing arrangement. They were based on a patent from the 1960s. I built a system using this arrangement using short dipoles in the early 90's.

Do you use 1 feed line and a load at each far end?

[K1JJ]

Jack 2 inch 1/8 wall will be fine if you use the guy cable truss. I'm glad Tom talked me into it. I used 1/4 inch guy wire. I was surprised how easily I could bend the tubing once it was bolted to the tower. I think you could stand on it now.

Very nice job, OM. Yep, you could probably walk out on that boom now.  A great breadboard for experiments now.

I use overhead trussing on EVERY boom that will bear weight... especially for those surprise ice storms that happen overnight.  The only thing to worry about now is the 45 degree side bend under ice load, but the dipoles will help guy the booms sideways. Though, a big ice load will still pull the boom sideways to down.

Here's a picture of my own boom installation. It's new, just put up two months ago. It uses a 3.5" diameter center with 3" extensions to 2.5" ends, 1/8" wall. It's 40' long and sits at about 188' using 1/4" cable overhead trussing. It uses TWO overhead trusses - one out 7' and the other out 19' from center. The shot is a little fuzzy cuz of the telephoto shot needed. (no tripod)  I tried to squeeze as much height as I could outa it....  Pulled it up using the car and a group of well placed pulleys /ropes.

Notice the sidearm and the safety rope. The boom hangs on a steel "swivel" and puts no twisting torque on the tower. It is guyed by the delta loops. In the wind there is a slight back and forth swing to it. Torque can take down a tower so I go to great pains to minimize it when I can.

The delta loops for 75M are switchable NE/SW using the HUZman's coax stub technique.  On the tower at the end of the coax stubs I add a coil to make the loop a reflector and drive the second loop directly with a balun. Switching directions simply switches the connections to each loop coax - with the relay.  20-30db front to back reports are common using this system.

T

[WA1GFZ]

Steve cool on the phasing like a delay between two directional couplers speed of light related not frequency. I wonder if I could use your reverse pattern switching at the end of a long coax by switching an open or shorted stub. My feed lines are 100 feet long and would like to switching in the house.

[Todd, KA1KAQ]

Nice looking setup, Frank. Looks a lot better in the daylight. It'll be great having you on 40 as a regular soon.

After calling CQ on AM with no replies over the weekend, I decided to haul the KWM-380 you fixed for me up off the floor for some DX work. Managed to snag Belgium, Ireland, Germany, and Romania with a pissweak 100 watts into a paltry half wave dipole up about 15'. Heard a 9K2 in there really light copy, Johnny sez it was Kuwait(!). Fun stuff, takes me back to my DX days of the mid-80s.

Heard the HUZman holding court down around 7133 talking with Ian GI3DZE and a few others, tag-teaming with a K2 station. Those phased loops really do the trick for the DX Cannon. 

[Steve - WB3HUZ]

That was Steve, K2 Fuzzy Wuzzy. You'll find him running AM on 75 meters on weekend mornings. He has a nice 2-el Yagi at 90 feet on 40 meters.

We we get your antenners up proper, you'll be WHIRL WIDE.

BTW, I heard some moron slopbucket on 3740 kHz the other day bragging about his 20 meter beam and how he worked Spain. BFD, you just did better that on 40 meters. Working DX on 20 is like shooting fish in a barrel.

[WA1GFZ]

Well just got off 40 and worked an IK.. VSWR sucked and FB only 2 S Units so kept it at 50 watts. Then did a sweep. resonates nicely at 7.4 MHz. I should have not chopped the ends last week when it was closer to the ground. 

[K1JJ]

Well just got off 40 and worked an IK.. VSWR sucked and FB only 2 S Units so kept it at 50 watts. Then did a sweep. resonates nicely at 7.4 MHz. I should have not chopped the ends last week when it was closer to the ground. 

Keep playing wid the configs until you zero in on big results. I wud stick up a ref dipole, even if it is low and at right angles... just to have a baseline.  There IS a perfect situation for you QTH - you just have to find it. It took me years to finally figure it out here.

My own breakthrough was discovering phased beverages, stacking for low angles, canceling high angle lobes, fine tuning for maximum f-b and dual diversity receiving.   Receiving is what matters. Transmitting takes care of itself.

T

[Steve - WB3HUZ]

If you are going the phasing route, make the two dipoles the same. Then determine the feedpoint impedance and cut your phasing lines appropriately.

If you go the parasitic route, cut each dipole to the desired freq independently (you don't want any interaction). I would cut them high in frequency since it's likely once you add the second element the resonant frequency will drop. Then connect your stubs and check the freq. Trim the length of both dipoles as needed to get the resonant freq where you want it.