2m V4k

[HomerBB]

Homebrew 2 meter Vector 4000 in progress. Put it up 21' and QSO'd local for first check on it. Simplex FM 146.520 Mhz contact 16 miles apart got good reports on 5 watts and 100 watts out. S4 on 5w, s9+ on 100w. Receive was good, too. S3 on my IC-746 other station transmitting at 5w, S9 other station transmitting 100w. SSB was clean and strong.
I have some refinement of the components but well pleased so far.

 

[HomerBB]

Had a few minutes to wrangle with this antenna before dark today. Improved the feedpoint to make it more stable. Experimented a little with another gamma match.
At the moment SWR is:
1 6:1 -----144 Mhz,
1.5:1 ----- 145 Mhz,
1.4:1 ----- 146 Mhz,
1.3:1 ----- 146.52 Mhz,
1.3:1 ----- 147 Mhz,
1.3:1 ----- 148 Mhz.

 

[w9cll]

Awesome work!

 

[543_Dallas]

Very cool. Any plans for a 160m version?

 

[HomerBB]

Very cool. Any plans for a 160m version?

Ah, sure. Maybe tomorrow...

 

[rigmo]

Hi all, Hi 2 for HomerBB
Im looking for good antenna for my fm experiment... and all my search leeds me to vertical antena; Vector dominator... exterminator antenna, meany different names but the same type.. to meany fights between suppliers..?!
I find one supplayer 200km from me... I write him but answer was.. contact guy from USA ( 100000km..) insane..! we do not business with private person.. !

I see meany home projects And Im intrested build my Owen, ITs more chiper... but I do not anything.. ... any details... I se meany photos... angles diameters... etc etc..

Can you help me to build my own VECTOR for FM BaND

Thank You in ADVANCE
BEst REgards

 

[HomerBB]

Howdy, Rigmo.
When I built this little antenna I did not have a resource for dimensions. I attempted to scale the 2m version directly from an 11m model.
Here are some measurements to start with. But, I will caution that the thing is temperamental to small changes and will move rapidly away from a good tune in a hurry.
I got mine to work, then moved on to other things so never locked down anything to replicate exactly.

Where I started..

2m
Length - 62.125" (40" w/CH 10")
Radials - 20"
Ring - 5.647" diameter
Gamma rod - 10"
Gamma body - 5"
1-5/8" radials attached from bottom

Modifications:
2m
57.6" vertical
19.2" radials
17.5" hoop circumference.

 

[rigmo]

I see and understood your point, sensitivity.
how you get ring diameter ? lambda ?
On some portal i read angle is 14°

 

[rigmo]

2m
Length - 62.125" (40" w/CH 10")
Radials - 20"

I see and understood your point, sensitivity.
how you get ring diameter ? lambda ?
On some portal i read angle is possible 14°

 

[HomerBB]

I just went at it in a straight forward scaling effort.
Don't know whether my dimensions were/are correct.
Used antenna calculator to find difference between the lengths of each vertical, the 27mhz antenna is 5.35x the 146.52mhz antenna length. Divided the 11m ring diameter , 30", by 5.35 for 2m ring diameter of 5.6".
I used that formula for all dimensions then experimented for modifications using analyzer.

 

[Shadetree Mechanic]

Here is a thread that explains some of the theory. It is a long read but has tons of info.
https://www.worldwidedx.com/threads/modified-vector-4000.36412/