AirNav Systems Forum

AirNav Radar => AirNav Radar Discussion => Topic started by: Johnn on February 21, 2009, 03:24:32 PM

Title: Please Help - Antenna
Post by: Johnn on February 21, 2009, 03:24:32 PM
Hello,
What I would like to know is if I use 15 meters of cable, will this affect signal loss alot?
the cable is this: 'Radar-CBL-15M 15M ultra low loss cable assembly (includes all connectors) £49.95' - I presume I dont need to fit any connectors to the cable.
I am buying from this site: http://www.bhinstrumentation.co.uk/html/_airnav_radarbox.html

If I go longer than 15m, is the signal going to worse and affect my range?

Thanks John
Title: Re: Please Help - Antenna
Post by: CoastGuardJon on February 21, 2009, 03:33:12 PM
Hi John, the simple answer is the longer the cable, the more attenuation to the signal!   15m of a heavy co-ax may cause less loss/attenuation than 5mA thin one.   A lightweight co-ax will cause more loss than a great thick heavy one, but the thicker one will be much stiffer and doesn't like tight curves.   Connectors fitted to the box end of the cable can stop you threading the cable through a hole.   Personally, I'd always go for a thin, flexible 150mm "patch" lead from the heavy downlead to the box.   Plenty of posts in here to different makes/specs of cable - search for Westflex, Ecoflex, Garex.
Title: Re: Please Help - Antenna
Post by: Johnn on February 21, 2009, 03:36:27 PM
hey Thanks for the reply - So I should keep away from the cable I have in mind?
Thanks
Title: Re: Please Help - Antenna
Post by: anorak on February 21, 2009, 04:09:44 PM
Hi John  I`ve just put a SSE-1090SJ mk 2 ANTENNA connected to 20mt of westflex 103 on N fittings with a 1mt pigtail it certainly improved my reception.

Title: Re: Please Help - Antenna
Post by: CoastGuardJon on February 21, 2009, 05:21:27 PM
Quote from: Johnn on February 21, 2009, 03:36:27 PM
hey Thanks for the reply - So I should keep away from the cable I have in mind?
Thanks

Hi John, no, not at all, I hadn't even looked at the link!   I was referring to RF co-ax in general.  Measure just how long a run you need and add a couple of metres to allow a 360 degree loop in the cable, if you're going for an external antenna, and another loop in under the eaves.