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Best antenna for the UBC125XLT?

PostPosted: Mon Jan 23, 2017 11:04 pm
by nufc1985
I bought a better antenna for my 125XLT (as shown below), and it is a vast improvement on the stock antenma. But what antenna do you guys recommend?

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Re: Best antenna for the UBC125XLT?

PostPosted: Wed Mar 15, 2017 8:22 pm
by zerocool
I myself use the blackdiamond and i cannot fault it, also works well with rtlsdr dongle.

http://www.radioworld.co.uk/black_diamond-antenna25_to_1500_mhz
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Re: Best antenna for the UBC125XLT?

PostPosted: Wed Mar 15, 2017 9:15 pm
by m0lsx
What do you want to use the antenna for?
General listening, mainly airband, mainly radio amateur bands, mainly marine??
Also where do you want to use the antenna?
I have used those micro mags for years, as my scanner antenna of choice for my car.
For home base use there are much better options & for out & about handheld use other options.
Also if it's for homebase use, do you have any limitations on what you could use?
I am not in general a fan of scanner vertical antennas such as the one linked to above, but I am a fan of Sanpiper antennas. I have several of their antennas & all have been well made & value for money.
http://www.sandpiperaerials.com/

Re: Best antenna for the UBC125XLT?

PostPosted: Thu Mar 16, 2017 1:17 pm
by scan_8051
Hi ,I am mostly listening to the Air band,of course the plains in the
air can be heard with the standard antenna,but the groundstations
cant be heard,so I tried to build a Yagi antenna.

The Yagi is specifically designed for a feed impedance of 50Ω,
Though having a narrower bandwidth,they provide high gain near the design frequency.
Its a 5 element air band Yagi ,dimensions are calculated with the 4nec2 simulatie tool.

I am not a transmission or antenna specialist but ,didn't use an antenna-analyser
but it seems to work with my UBC125XLT

Re: Best antenna for the UBC125XLT?

PostPosted: Thu Mar 16, 2017 2:09 pm
by m0lsx
scan_8051 wrote: The Yagi is specifically designed for a feed impedance of 50Ω,


A Yagi does not have an impedance of 50 Ohms, which is why they use a Gamma match or need a balun or a suitable length of 75 Ohm coax to create a match.
If you are going to be using a Yagi on Airband for the ground stations, don't forget it will need to be vertically polarised.
Also look at the topography between you & the ground stations you want to hear, as even with a beam, if there is a land rise between you & what you want to hear, then the chances are, you will hear nothing.

Re: Best antenna for the UBC125XLT?

PostPosted: Fri Mar 17, 2017 9:00 am
by scan_8051
This Yagi is specifically designed for a feed impedance of 50 Ohm .
The 4nec2 simulatie tool,will determine the spacing and length
off the elements,the closer the spacing, the lower the feedpoint impedance etc.

I tried a choke 1:1 balun but this makes no difference with this configuration.
So I left it out.

Yes,you're right it must be vertically polarised, no landrises here :smiles: (the netherlands).

Re: Best antenna for the UBC125XLT?

PostPosted: Fri Mar 17, 2017 12:49 pm
by m0lsx
scan_8051 wrote:This Yagi is specifically designed for a feed impedance of 50 Ohm .


The problem is 50 ohms is not achievable, without reactance that needs getting rid of. That is why high quality beams are made the way they are. By nature a Yagi is NOT 50 ohms, but should show a SWR of around 2:1.
Get a good quality manual ATU & see how many places you can see a SWR of 1:1.1. It is not one. But two & possibly three. 50 ohms at the SWR meter is not always what it seems.

Re: Best antenna for the UBC125XLT?

PostPosted: Sun Mar 19, 2017 8:25 am
by Minus1
I've just acquired a Watson W881 mobile whip.
Whilst it is early days, it shows a noticeable improvement over the standard Uniden antenna.
It is 2.45 times longer than the standard antenna so not exactly suitable for in pocket use, but I didn't buy it for that.

Birmingham ATIS 136.025
Standard - Signal bars 3/5
Watson W881 - 5/5

London Volmet South 128.6 (Actually 128.5925 from Clee Hill)
Standard - 0/5
Watson W881 - 1/5

Re: Best antenna for the UBC125XLT?

PostPosted: Sun Mar 19, 2017 3:33 pm
by stanogs68
decent price whats the improvement like ?

Re: Best antenna for the UBC125XLT?

PostPosted: Sun Mar 19, 2017 11:14 pm
by ur5by9
I'm using a Diamond X50 works a treat

My Antenna

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