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Homer's Qv4k

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Remember I'm still working on it. Weather and work keeps me from getting the edges smoothed out on this thing. The gamma strap is a temp one until I find my sweet spot, then the hard mount will go on it. The spreader is a cable/rope spool cut in half supporting PVC nipples notched on the ends to fit the radials, and held on with UV resistant zip ties.
My camera is doing all kinds of weird things; bending and warping thing that are not shaped like that!
 
hey homer , do they sell that size pex pipe at homedepot ? if so can you post a link to it . im not finding that size when i look . it could just be my local stores dont carry it , but if i can get a skew number for it i could order it ...... if its not to expensive for my cheap azz :D .

i'm looking forward to reading your results from the changes you're making ;)
 
I'll check our inventory, but I think I got it at the local hardware store.
The new size rod extended about 3" brought SWR to 1.1:1 on 40 and 1.2:1 on ch1 needs more to get wider banded.
 
BOOTY MONSTER said:
hey homer , do they sell that size pex pipe at homedepot ? if so can you post a link to it . im not finding that size when i look . it could just be my local stores dont carry it , but if i can get a skew number for it i could order it ...... if its not to expensive for my cheap azz :D .

i'm looking forward to reading your results from the changes you're making ;)
Click to expand...

Here you go, Booty.

1/2" x 3/8" x 5' PEX SKU: 540749 price in Arkansas $1.98 ea

1/2" x 3/8" x 10' PEX SKU: 556874 price in Arkansas $3.96 ea

5 Ft. Hot/Cold Pipe - Straight Lengths - White - QB2PS5X at The Home Depot

SharkBite 3/8 in. x 10 ft. White PEX Pipe - U855W10 at The Home Depot

HomerBB said:
The new size rod extended about 3" brought SWR to 1.1:1 on 40 and 1.2:1 on ch1 needs more to get wider banded.
Click to expand...
I meant to say extended 3" from the bottom where the 1/4" rod had to go to get lowest SWR. Now I'll need to work on the exact lengths for the radials and vertical, and work on the permanent Gamma strap position.
 
Assembly notes on the Qv4k:

I started with the tubing for the vertical element. Here it is assembled to full length.

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I used these 4' fiberglass rods coupled together with pieces of tubing to form the radials.

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The ring is formed from a 10' joint of PEX tubing cut to the necessary to form a ring of 31" diameter. The PEX I covered with Aluminum tube the same as the radials to provide conductive skins. The ends of the PEX tube were solidified by inserting a short dowel in them, and connected together with a conduit coupler.

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The bottoms of the radials were connected to the vertical mast by means of electrical terminals, while the tops were connected to the ring and kept rigid by means of spaces made of a wire/rope spool and PVC nipples.

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It lies in the backyard awaiting the Gamma match to ready it for tuning.

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The gamma is made of a 1/2" ID tube 17.25" long, and a 3/8" x 36" rod insulated by a piece of PEX tube.The upper tube cap does double duty as the spacer, a rubber stopper.

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The Gamma is installed and a stand-off strap made of 3/4" x 1/8" aluminum strap helps hold the rod and tune the antenna.

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In the air for tuning.

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homer , my hat is off to you . you sir are a true home brewer (y). you truly make stuff out of what you have around . nice work , and nice talking to ya on the LL tonight to :)

have you decided on a starting point for your basket elements , vertical length and gamma tap point yet ? btw , nice area to work in ;)
 
In the post above about the assembly notes the paragraph describing the ring should read:

The ring is formed from a 10' joint of PEX tubing cut to the necessary length to form a ring of 31" diameter. The PEX I covered with aluminum tape the same as the radials to provide conductive skins. The ends of the PEX tube were solidified by inserting a short dowel in them, and connected together with a conduit coupler.
Click to expand...
 
I put the Qv4k up as shown in the photo using the dimensions of:

Length of vertical -------------- 29' 8" (accidental length)
Radial lengths ------------------ 108"
Gamma Match --------------------- 17.25" tube, 36" x 1/4" rod
tap point of Gamma to vertical -- 30" up from bottom of Gamma
rod set ------------------------- 1" off bottom of Gamma

SWR:

28.755 -------------------------- 2.5:1
28.305 -------------------------- 2.0:1
27.855 -------------------------- 1.2:1
27.405 -------------------------- 1.0:1
27.205 -------------------------- 1.0:1
26.965 -------------------------- 1.05:1
26.515 -------------------------- 1.4:1
26.065 -------------------------- 1.1:1
25.615 -------------------------- 1.1:1
25.165 -------------------------- 1.0:1

Next I used the dimensions from the posted graphic on the Vector 4000 thread:

Length of Vertical -------------- 27' 10"
Radial lengths ------------------ 106.75"
Gamma Match --------------------- 17.25" tube, 36" x 3/8" rod
tap point of Gamma to vertical -- 27" up from bottom of Gamma
rod set ------------------------- 4" off bottom of Gamma

SWR:

28.755 -------------------------- 3+
28.305 -------------------------- 1.7:1
27.855 -------------------------- 1.0:1
27.405 -------------------------- 1.1:1
27.205 -------------------------- 1.5:1
26.965 -------------------------- 1.5:1
26.515 -------------------------- 1.3:1
26.065 -------------------------- 1.5:1
25.615 -------------------------- 3+
25.165 -------------------------- 3+

Needless to say that wasn't looking too good, so:

Length of vertical -------------- 28' 10" (compromise length)
Radial lengths ------------------ 106.75"
Gamma Match --------------------- 17.25" tube, 36" x 3/8" rod
tap point of Gamma to vertical -- 30" up from bottom of Gamma
rod set ------------------------- 7" off bottom of Gamma

SWR:

28.755 -------------------------- 2.6:1
28.305 -------------------------- 1.9:1
27.855 -------------------------- 1.15:1
27.405 -------------------------- 1.0:1
27.205 -------------------------- 1.0:1
26.965 -------------------------- 1.0:1
26.515 -------------------------- 1.2:1
26.065 -------------------------- 1.2:1
25.615 -------------------------- 1.0:1
25.165 -------------------------- 1.0:1

The weather has shut down any movement on the antenna for now. I don't know what to think of the odd SWR wavy shape, but I'm hoping that getting the antenna higher in the air away from the house will help me to see a more customary curve. I am wondering what it will take to get the curve further up the band toward 10 meters. I want it for 11 meters, but favoring a curve toward 10 meters.

Ideas?
 
Homer, I don't think I would worry a second if the indications were accurate and I had an SWR less than 1.2:1 from 27.855 to less than 25.000 mhz with a high gain 11 meter vertical monopole using a matching device.

Did you notice any wattage output differences on your radio at the various frequencies you checked?

I think maybe with the changes you made in your tune you may be close, but you may have gone right past the sweet spot...shifting from being capacitive to inductive or visa versa. When I see this happen I suspect that I'm just chasing my tail, and I cut my range for adjustments to a 1/4" or even a 1/8" per iteration.

You might check an see if the Vector thread numbers you used did or didn't include a small top hat on top that is not included in the overall measurements. That could make 4"-8" difference if the measurements came from the New Vector 4000. I say this, because it is the shortest overall, showing realistically the best curve for the frequency range tested, yet it ended up a little high in the range of your radio...which I think is a modified CB.

With your limitation to frequency range above and below CB, it will be hard for you to really tell, but my Sigma4 shows about 1.9 - 2.45 mhz bandwidth <2.0:1. You might check with Bob and Mac, about what their bandwidth measurements were/are they might be much better.

Will you be changing your feed line when you mount it on your tilt-over mast? If so, I would surely expect to see things change.
 
Last edited:
Yes to changing the feedline. The current one is too short to stay, and the other will be one continuous 89' length.

I may have to just move it from where it is before going to the tip over mast because of the constant rain here with a few minutes of reprieve at a time.

I'd be interested in the exact lengths both Bob and SW used for theirs. Right now going bacK to the other threads is like mining for bits of minerals in the mountains!

As for output, on the external AVG/PEP meter shows more action with the least flat match, but I'll have to record it to be sure that remain true at all times.
 
homer , can you adjust the length of your vertical without cutting it ?
higher frequencies (or lower bands) use shorter antennas . if you can shorten your main vertical and basket elements it should make the antenna more resonate in the direction of your preferred frequencies . divide 492 by the center frequency of your main target area or maybe make it a little higher/longer to keep 11 meters friendly with the swr meter . and of course re-tune the antenna with the gamma match . hopefully shockwave can confirm if my idea has any merit .
 

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