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AirNav RadarBox and RadarBox24.com => AirNav RadarBox and RadarBox24.com Discussion => Topic started by: Wer3Y on August 05, 2008, 07:09:14 AM

Title: Is it possible..?
Post by: Wer3Y on August 05, 2008, 07:09:14 AM
is it possible to connect two or more antenna's on "1" RB..?
lets say 2 diffrent antenna's at diffrent locations at the same building.
maybe a Cable adaptor with 2 inputs and 1 output..?
Title: Re: Is it possible..?
Post by: flightchecker on August 05, 2008, 09:41:20 AM
It is !

by for instance using a "Powersplitter" (according to its name "splits" the input power applied to one of its "arms"  (inputs) between two (or more) others. Tradeoff beeing a power loss of 3db (half of the inserted power) in each of the arms in case of the "3db splitter". Vice versa, two antennas may be connected to the output arms,  and the input arm then to the receiver. A loss of 3db of input power (still talking about "power", even it is almost "tiny" input signals in case of a "receiver") the resulting tradeoff  to both of the input signals again of course.   
There are (expensive) "active" splitters available as compared to the above "passive" devices, suffering less "insertion loss", as compensated by means of amplification.

Another idea might be to use a "coaxial switch" at the end of both feederlines (as they come into your "shack"), thus manually selecting between one or the other antenna, or a "coaxial relay" (mounted "near" the antennas) to "directly" switch between them. Advantage beeing just one "coax" only to run down, disadvantage  a "control voltage" to be supplied to the relay for its "switching" (Needs one "control" line, "ground" supplied via the coaxial cables outer conducter[shield])

Don't be "simple minded" by just connecting the coaxial feeder lines in parallel. It "works"
but is not a solution from a "high frequencies point of view".

Karl
Title: Re: Is it possible..?
Post by: Wer3Y on August 06, 2008, 03:49:46 PM
Thank you so much Karl for your replay..
i got it now ;)
Title: Re: Is it possible..?
Post by: flightchecker on August 06, 2008, 04:13:26 PM
You're welcome Wer3Y,


Karl
Title: Re: Is it possible..?
Post by: juangelb on August 08, 2008, 01:51:52 AM
Ok, flightchecker is fully right....

But You can try..... because in doig so, You will not put in risk Your RB al all....
here I did a lot of testing on this (Two antenas and also 3 for one RB and even SBS-1),
Contructed several antenas.... and played a lot.... never had a RB or SBS-1 damaged.
Obviously there are LOTS of technical matters about this, as two or more antenas being in phase....
But for testing .... and playing, it is not needed to be am RF Engeneer....
So, play with this, and be happy.

Cheers. Juan
Title: Re: Is it possible..?
Post by: flightchecker on August 08, 2008, 07:42:25 AM
Right of course Juan,

should have had mentioned that before. Not a problem at all, go ahead and give it a try Wer3Y
 

Kind regards

Karl