AirNav Systems Forum

AirNav RadarBox and RadarBox24.com => AirNav RadarBox and RadarBox24.com Discussion => Topic started by: daveg4otu on April 26, 2009, 10:05:48 AM

Title: Antenna cables- extension
Post by: daveg4otu on April 26, 2009, 10:05:48 AM: Using the supplied antenna here-with good results considering the location.

At the moment the antenna is on a biscuit tin - on the roof just outside - at about the limit of the cable.

Soon(with luck ) I will have a vacant spot on the mast that carries my VHF/Air antenna(this will extend my coverage to the west considerably) ... but will need longer cable perhaps 5metres more - does anyone supply extension antenna cables pre-fitted with the correct connectors for ANRB...or if not - does anyone supply the connectors/plugs...if so exactly what are they called?

MTIA

Dave
Title: Re: Antenna cables- extension
Post by: nortonbeak on April 26, 2009, 10:58:53 AM: I think that there is a general consensus that the supplied antenna would not be suitable for prolonged external use. Certainly not if you are UK based.

So you would probably need to select an after-market antenna (of which there are many) and some suitable cable.

If you are UK based then cable perhaps from

http://whwestlake.110mb.com/cable-wire.pdf (http://whwestlake.110mb.com/cable-wire.pdf)
Title: Re: Antenna cables- extension
Post by: Dazzlercee on April 26, 2009, 03:18:47 PM: What is the problem with mounting the standard antenna outside?

Mine is on a disused flue on the roof with the Radarbox in the loft.
The manual clearly states that the supplied antenna is NOT an internal antenna and to mount outside for best results.

Have there been a number of failures when mounted externally?

Daz
Title: Re: Antenna cables- extension
Post by: Allocator on April 26, 2009, 03:30:10 PM: I used the standard antenna outside on the Velux roof window for months after I got my RB, it didn't seem to come to any harm. I stand it outside on the window ledge in the rain every now and then, and it's fine.

One of the biggest killers of any antenna mounted outside is water getting into the co-ax as it just sucks it up like a sponge. That and corrosion causing a lack of electrical contact between the antenna and the cable.
Title: Re: Antenna cables- extension
Post by: WAL 2T on April 26, 2009, 03:36:25 PM: Had mine out above the gutter for about 18 months in all weathers and not had any problems with the antenna itself or the feeder. The ground plane disk does corrode though and start to shed it's paint if that is also placed outside.
Title: Re: Antenna cables- extension
Post by: malc41 on April 27, 2009, 08:53:54 AM: WHich is the best cable to buy though if you are thinking of extending the cable by say 5m?
Title: Re: Antenna cables- extension
Post by: WAL 2T on April 27, 2009, 03:43:28 PM: Quote from: malc41 on April 27, 2009, 08:53:54 AM
WHich is the best cable to buy though if you are thinking of extending the cable by say 5m?

LMR400 or Westflex 103. You can now get hold of large entry crimp-on SMA connectors for the above in both male and female flavours which would allow you to make up a suitable extension for the supplied antenna (male one end and female at the other). Just have to be careful that the feeder is secured carefully so it's weight doesn't destabilise the antenna.

Link to connectors:

http://www.connextech.co.uk/lmr400-connectors-8-c.asp
Title: Re: Antenna cables- extension
Post by: bailey_uk on April 27, 2009, 03:53:09 PM: Just out of interest, am I right in thinking that when using Westflex 103, that there isnt a connector to use directly to the RB? Hence a patch lead is needed?
Title: Re: Antenna cables- extension
Post by: WAL 2T on April 27, 2009, 04:22:32 PM: Quote from: bailey_uk on April 27, 2009, 03:53:09 PM
Just out of interest, am I right in thinking that when using Westflex 103, that there isnt a connector to use directly to the RB? Hence a patch lead is needed?

As per above you can now buy large entry SMA connectors which will suit the larger diameter cables such as 103 and LMR400 so you could have a single run feeder with an external antenna (n-type to sma). If you're referring to the radar extender kit; a patch lead is included to connect the radar box to the BNC connection on the BIAS-T.
Title: Re: Antenna cables- extension
Post by: bailey_uk on April 27, 2009, 04:32:01 PM: Ah if only id of known that yesterday!

I have just purchased from Westlakes, a 8m length of '103' with a patchlead for connection to my RB.

Is there substantial signal loss by using a patch lead instead of one of those new large entry SMA connectors?
Title: Re: Antenna cables- extension
Post by: WAL 2T on April 27, 2009, 06:15:36 PM: If the patch lead is made with RG58 I would be inclined to ditch it (even a small run).
Title: Re: Antenna cables- extension
Post by: bailey_uk on April 27, 2009, 07:07:10 PM: William Westlake is making it for me, and posted it today so will find out when it arrives!
Title: Re: Antenna cables- extension
Post by: malc41 on April 28, 2009, 08:48:27 AM: WAL2T

Thanks for the info
Title: Re: Antenna cables- extension
Post by: bailey_uk on April 28, 2009, 11:10:19 AM: Yeh the patch lead is RG58.

I am still going to use it, as it will be a huge improvement from the supplied RB one. And then after a while, have a go at soldering one on myself. How do they differ from soldiering a pl259?
Title: Re: Antenna cables- extension
Post by: nortonbeak on April 28, 2009, 11:34:27 AM: Quote from: bailey_uk on April 28, 2009, 11:10:19 AM
How do they differ from soldiering a pl259?

If you mean by "they" an SMA plug, then not a lot. The central pin is just smaller.

The SMA plugs from Maplin have a crimp fitting around the braid rather than the clamp fitting of the PL259.