AirNav Systems Forum

AirNav RadarBox and RadarBox24.com => AirNav RadarBox and RadarBox24.com Discussion => Topic started by: Xpress690 on August 01, 2017, 11:40:07 pm

Title: 2 Boxes 1 antenna
Post by: Xpress690 on August 01, 2017, 11:40:07 pm
Hi all

As anyone tryed to install 2 boxes with 1 antenna only??
Does´t work? What do you need to make it work??

Regards

Paul
Title: Re: 2 Boxes 1 antenna
Post by: Kenny on August 02, 2017, 03:03:53 am
Hi,

I use this splitter from Mini-Circuits.  Works like charm for over 2 years.

ZAPD-20 0.7-2.0 GHZ POWER SPLITTER COMBINER COAXIAL RF

Kenny
Title: Re: 2 Boxes 1 antenna
Post by: Xpress690 on August 02, 2017, 08:25:54 am
Kenny

Thank you for your response, all I need now is a place where I can buy one.

Regards

Paulo
Title: Re: 2 Boxes 1 antenna
Post by: Runway 31 on August 02, 2017, 08:36:21 am
Lots found using Google, just got to get the correct type

Alan
Title: Re: 2 Boxes 1 antenna
Post by: YARM.Armidale on September 03, 2017, 10:37:57 am
Do a search in eBay for Item # 111914160361 which is the one I recently purchased. This will be the third one I have. I run a Kuhne 1090 lna into a "t" that feeds the two I have running now, then I have "a number of receivers" (wont divulge how many) and guessing it gives it away that I need another one. But, I can say, some feed RB, FA, PF, and FR just to name a few.

Trust me, you will be doing yourself a great justice by getting your hands on one of these if you want multiple receivers off a single antenna.

Point to note: it really does point out which company receivers are the most sensitive and give the best coverage.

Regards,
yarm.armidale
Title: Re: 2 Boxes 1 antenna
Post by: NigelR on September 03, 2017, 10:35:52 pm
I've tried searching in eBay for this item number but can't find anything. Please could you provide more details.

Thanks
Title: Re: 2 Boxes 1 antenna
Post by: CYYZGUY on September 04, 2017, 06:15:03 pm
Hey Nigel, I just purchased this a few weeks ago, have been running 2 antenna's on it flawlessly, and a very cheap price!

Now this is on the Amazon.ca website, since I live in Canada, but you may be able to get it on Amazon in your country as well.

https://www.amazon.ca/gp/product/B01FH9EJMS/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1

My incoming cable is LMR-400 Male, which goes in to the Female on the splitter.  I then purchased a N Male to Sma Male for my radarbox, likewise for my NooElec Dongle.

I can also say I noticed NO loss in signal when I did the split, I am getting the same high volume of aircraft that I always do.



Jason
Title: Re: 2 Boxes 1 antenna
Post by: NigelR on September 06, 2017, 08:55:27 pm
Thanks Jason

The splitter you recommend is not available in the UK and there is no delivery of it to the UK from the US or Canada. I have ordered something which has a very similar spec to the one you recommended so I'll see how that goes when it arrives.

Thank you again

Nigel
Title: Re: 2 Boxes 1 antenna
Post by: abcd567 on September 07, 2017, 12:50:34 am

I can also say I noticed NO loss in signal when I did the split, I am getting the same high volume of aircraft that I always do.

This is possible only if there is something in your system which compensates the insertion loss of the splitter. It can possibly be:

(a) An rf amplifier somewhere in your system.
OR
(b) A very high gain antenna, with gain greater than 6 dBi.

Two way splitters normally have insertion loss between 3 dB and 6dB. Good costly ones have loss close to 3dB, while regular quality (used for TV and Satellite) close to 6dB.

Most sellers and manufacturers do not declare their insertion loss, but few do declare. I am posting photo of such a splitter which claims "low loss" with an insertion loss of 3.5 dB/5.9 dB.

For those who are not familier with dB, an insertion loss of 3dB means the output signal is 1/2 of input, and 6dB means output signal is 1/4 of input signal! :(

(https://s20.postimg.org/677jrg5dp/Splitter_insertion_loss.jpg)


Title: Re: 2 Boxes 1 antenna
Post by: abcd567 on September 07, 2017, 01:09:06 am
Hey Nigel, I just purchased this a few weeks ago, have been running 2 antenna's on it flawlessly

https://www.amazon.ca/gp/product/B01FH9EJMS/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1


Description
Power splitter, professional signal power divider device.
Wideband 800-2500MHz powder splitter,perfect for GSM/CDMA/3G/4G signal.
Frequency Range: 800-2500MHz
Impedance: 50Ω
Insertion Loss: ≤3.1db/5.1db/6.1db
Input Maximum CW: 50W/50W/200W
Connector type: N-female
VSWR: 1:1.3
Size(Length*Width*Height):5.3"x3.3"x0.8"
Note: Please note about the connector type before purchasing.

(https://images-na.ssl-images-amazon.com/images/I/51I0p32ZWbL._SY400_.jpg)

Title: Re: 2 Boxes 1 antenna
Post by: CYYZGUY on September 07, 2017, 10:58:37 am
abcd567  I can only tell you the results I am seeing.  I have been doing this for a long long long time now.  I have had antennas up on top of apartment buildings, endless runs of LMR400 cable with CO-AX seal etc etc.   My cabling and infrastructure is top tier.  I have spent more money then I can count on connections, antenna's etc.  I am running the DPD ADSB Antenna and it has served me very well for years.  In terms of the total # of aircraft being displayed at any given time, it is no less then it was before...  I average on a busy day 200+ aircraft....

I will post an updated picture of my polar diagram tonight once I am home. 

Both of my stations...

https://www.radarbox24.com/stations/PGANRB113376

https://www.radarbox24.com/stations/EXTSHA192269

Unfortunatley my ranking is down on both due to my uptime.  I have had some power issues over the last few weeks and they finally changed out the transformer on my street yesterday  (was leaking oil and causing power spikes/dips)  Power was out for over 5 hours...ughhh

(https://farm6.staticflickr.com/5792/20614152331_3433f1c753_h.jpg) (https://flic.kr/p/xpAViv)DSC_0305 (https://flic.kr/p/xpAViv) by CYYZGUY (https://www.flickr.com/photos/86721442@N07/), on Flickr


My Old setup...


(https://farm9.staticflickr.com/8031/8031204254_f5308a7f2c_h.jpg) (https://flic.kr/p/deG2dS)DSC_0756 (https://flic.kr/p/deG2dS) by CYYZGUY (https://www.flickr.com/photos/86721442@N07/), on Flickr



Title: Re: 2 Boxes 1 antenna
Post by: NigelR on September 07, 2017, 10:39:50 pm
This is the splitter that I've ordered. The insertion losses look very good (<0.1dB) but only time will tell.

Nigel

Title: Re: 2 Boxes 1 antenna
Post by: abcd567 on September 08, 2017, 12:52:24 am
This is the splitter that I've ordered. The insertion losses look very good (<0.1dB) but only time will tell.

Nigel
Good luck! Let us see results.
Aparently, the specs have been prepared by the manufacturer or seller in a misguiding way. A two way splitter splits the signal into two equal parts. As a result the output signal power is 1/2 of input power, which means 3 dB loss. In addition there are losses caused by resistance of the splitter, so the total insertion loss = splitting loss + resistive loss = 3 dB + (0.1 to 2.5 dB).

It seems the seller is simply declaring the resistive loss (0.1 dB) as "insertion loss", which is misguiding. If you check similar cavity filters by other sellers, say on ebay or amazon, you will see all of them declare "Insertion loss = 3.1 dB", and not 0.1 dB.