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Brian's new Antenna

Posted: Fri May 22, 2020 4:54 pm
by BriansBrain
:smoke

Got Brian a 100W Dominator :whistle

I'm fitting it this afternoon :tup
Domitaror+John-2.jpg

Re: Brian's new Antenna

Posted: Sat May 23, 2020 11:12 am
by BriansBrain
It's up :tup
Domitaror-1.jpg

Re: Brian's new Antenna

Posted: Sat May 23, 2020 1:58 pm
by tokingmenace
Looks good! Hope you get some good results.

Re: Brian's new Antenna

Posted: Sat May 23, 2020 2:38 pm
by NTRRadio
Looks like the same design as the old Sigma IV CB antenna. 7/8 wave?

Re: Brian's new Antenna

Posted: Sat May 23, 2020 3:27 pm
by BriansBrain
NTRRadio wrote: Sat May 23, 2020 2:38 pm Looks like the same design as the old Sigma IV CB antenna. 7/8 wave?
I think is it based on the Sigma yes :smoke

Re: Brian's new Antenna

Posted: Sat May 23, 2020 3:59 pm
by rigmo
The best antenna like two dipole but 7/8 is better..? where you buy? pcs is 3/4

Re: Brian's new Antenna

Posted: Sat May 23, 2020 4:03 pm
by rigmo
FM RF antenna Dominator Vector EXTERMINATOR 7/8" & 5/8"AlbumiFM RF antenna Dominator Vector EXTERMINATOR 7/8" & 5/8"
ASTROPLANE best vertical antenna ever? Sirio Vector 4000 avanti sigma 4 lw150 tagra bt-104 7/8" & 1 5/8".

https://www.worldwidedx.com/threads/ast ... 317/page-9

https://www.facebook.com/pg/k19radio/ph ... 0825969282

Re: Brian's new Antenna

Posted: Sat May 23, 2020 5:25 pm
by tokingmenace
NTRRadio wrote: Sat May 23, 2020 2:38 pm Looks like the same design as the old Sigma IV CB antenna. 7/8 wave?
Funnily enough I thought the same.

If correct, should work well then :smoke

Re: Brian's new Antenna

Posted: Sat May 23, 2020 6:39 pm
by NTRRadio
tokingmenace wrote: Sat May 23, 2020 5:25 pm
NTRRadio wrote: Sat May 23, 2020 2:38 pm Looks like the same design as the old Sigma IV CB antenna. 7/8 wave?
Funnily enough I thought the same.

If correct, should work well then :smoke
The old Sigma IV was a beast. I had one with intention to convert it to 88-108, but I ended up selling it instead.

Re: Brian's new Antenna

Posted: Sun May 24, 2020 11:54 am
by BriansBrain
rigmo wrote: Sat May 23, 2020 3:59 pm The best antenna like two dipole but 7/8 is better..? where you buy? pcs is 3/4
It's a real Dominator from the USA :tup

https://fmbroadcastantenna.com/dominator.html

Re: RE: Re: Brian's new Antenna

Posted: Sun May 24, 2020 12:37 pm
by Electronically
BriansBrain wrote:
rigmo wrote: Sat May 23, 2020 3:59 pm The best antenna like two dipole but 7/8 is better..? where you buy? pcs is 3/4
It's a real Dominator from the USA :tup

https://fmbroadcastantenna.com/dominator.html
3db that's pretty good for a dominator good choice Brian

Sent from my AMN-LX9 using Tapatalk


Re: Brian's new Antenna

Posted: Sun May 24, 2020 1:21 pm
by teckniqs
BriansBrain wrote: Sun May 24, 2020 11:54 am
rigmo wrote: Sat May 23, 2020 3:59 pm The best antenna like two dipole but 7/8 is better..? where you buy? pcs is 3/4
It's a real Dominator from the USA :tup

https://fmbroadcastantenna.com/dominator.html
"Max. power: 250 watts, 1KW or 3KW models"

....I thought your one was 100w version? I can't see that on the link posted up for the one you said you're using.

Re: Brian's new Antenna

Posted: Sun May 24, 2020 2:12 pm
by BriansBrain
teckniqs wrote: Sun May 24, 2020 1:21 pm
"Max. power: 250 watts, 1KW or 3KW models"

....I thought your one was 100w version? I can't see that on the link posted up for the one you said you're using.
Sorry... it's the 1000W version :oops:

Re: Brian's new Antenna

Posted: Sun May 24, 2020 2:51 pm
by fmuser877
how many miles does it go?

Re: Brian's new Antenna

Posted: Sun May 24, 2020 3:06 pm
by rigmo
fmuser877 wrote: Sun May 24, 2020 2:51 pm how many miles does it go?
depend of to many factors... distance from ground... ground configuration, earth natural disturbance...
but much better then one top quality dipole and also less then 2 way dipoles.
today wee need minimum 2 way or 4 way antenna sistem because rf jam is so high then was 25 years before...

I prefer dominator vector antena because hi get real gain easy to install. one antena like 2 way... but need the higher position... tower etc...

Re: Brian's new Antenna

Posted: Sun May 24, 2020 4:34 pm
by BriansBrain
fmuser877 wrote: Sun May 24, 2020 2:51 pm how many miles does it go?
he antenna is at 210m above sea level +/- 150m above average terrain (HAAT)
@ 140W I was getting a good results with the little dipole +/- 5 Miles or 8km

I have only had one report in up to now from Arguineguin with the new antenna...
... he said
very good connection now
.
With the dipole before it was a bit sketchy in Arguineguin.
Brian-Arguineguin-Terrain.jpg
I have not been out with my Pira to do a band scan yet :smoke
https://pira.cz/fm_broadcast_analyzer/?art=p275box
South GC Hillshade.jpg
:tup

Re: Brian's new Antenna

Posted: Sun May 24, 2020 7:09 pm
by fmuser877
I am pretty low down but getting about 8 miles in the car on 7 or 30 watts from my place you must have more hills around :(

Re: Brian's new Antenna

Posted: Mon May 25, 2020 1:22 am
by Albert H
I always found that a quick twin-stack of dipoles worked well, and gave around 3.2 dBb if matched and assembled correctly. The "Dominator" claims 3 dBd. My ⅞-wave with four ¼-wave radials measures at just over 3.7 dBd, and has a nice low radiation angle - very little signal goes skyward.

Another aerial I've been playing with (at 430 MHz so it's a reasonable size to work on) is the 0.64-wave vertical. The match is tricky, but when it works, it's very useful....

Re: Brian's new Antenna

Posted: Mon May 25, 2020 2:44 am
by thewisepranker
Albert H wrote: Mon May 25, 2020 1:22 am I always found that a quick twin-stack of dipoles worked well, and gave around 3.2 dBb if matched and assembled correctly.
I wouldn't call a correctly assembled and matched double stack, "quick", especially one that gets close to 3.2 dBd!

The last one I built took much, much longer I had anticipated by the time I:
  • Messed around trying to find a combination of aluminium box section and brass tube that gave me the impedance match that I wanted. I had to obviously go by commonly available sizes of box section, not listed in inside dimension order (which is all I really cared about) and brass tube listed in different units to the aluminium box section, and not available everywhere easily - this took at least 2 hours of calculation, simulation, compromise and lots of searching around to get right.
  • Used a milling machine that didn't have enough axis travel to make a quarter-wave splitter from aluminium box section and brass tube in one setup.
  • Built the quarter-wave splitter.
  • Checked the matching and tuning of the splitter using a VNA and some 50 Ohm loads from a cal kit and then adjusted as required. Hint: if it's wrong, you've got to start again or magically figure out how to make obround tapped holes.
  • Tuned the dipoles. This took about 4 hours.
  • Made the three pieces of coax with N connectors and hex crimp ferrules including carefully shrinking glue-filled heatshrink over the crimp sections to make them waterproof. Tip: do not buy anything but Amphenol, Pasternack, etc. (high quality, known-brand) crimp-type N connectors as the crimp ferrules will not be the correct size. They will not work with the supposed correct crimp die size. Time wasted: about 4 hours milling very hard tool steel in order to make my own crimp dies on said milling machine in order to make the ferrules grip the coax.
  • Checked the tuning when spaced for optimum gain (about 0.925 wavelengths) and spaced from the mounting pole, and adjusted to suit.

Re: Brian's new Antenna

Posted: Mon May 25, 2020 9:18 am
by teckniqs
BriansBrain wrote: Sun May 24, 2020 2:12 pm
teckniqs wrote: Sun May 24, 2020 1:21 pm
"Max. power: 250 watts, 1KW or 3KW models"

....I thought your one was 100w version? I can't see that on the link posted up for the one you said you're using.
Sorry... it's the 1000W version :oops:
Ahh OK, nice.

....So in that case if you've got the 1kW version and not the 250w version, does that mean you might be planning to use more power? :tup :whistle