AirNav Systems Forum

AirNav Radar => AirNav Radar Discussion => Topic started by: atcukmatty on June 06, 2009, 07:30:30 PM

Title: Has anyone put supplied aerial in loft? results?
Post by: atcukmatty on June 06, 2009, 07:30:30 PM
Hi, was wondering if anyone had put the antenna that is supplied with radarbox in the loft.... if so did it make much difference?

i am on the 2nd floor of my house and wondering if i raised the antenna another 20 foot higher to loft would it make much difference?

thanks
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: daveg4otu on June 06, 2009, 07:49:42 PM
Can't answer your question because until now mine has been outside - but - if and when I  get it repaired (just died again) I am now considering the the idea  of using the loft as a possibility .

The main question I would  want the answer to , which is equally relevant in your case is ...what level  of signal attenuation is likely through roof tiles?

Obviously - the higher the better - I've found even a couple of feet can make a difference in some cases - but  the  extra height may possibly be cancelled out by  the attenuation....

So - hopefully someone here may be able to offer advice from their own experience.
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: atcukmatty on June 06, 2009, 08:03:33 PM
well thinking about it i would say there would be more attenuation in the double layer of bricks than roof tiles?
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: daveg4otu on June 06, 2009, 08:08:08 PM
I think that obviously  that is going to be an improvement if you  presently have the antenna indoors somewhere- but   I  would  be interested in the attenuation as compared with  an antenna that is in the clear.
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: atcukmatty on June 06, 2009, 08:25:32 PM
so you had the supplied desktop antenna outside? what is the difference in signal from inside to outside?
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: tarbat on June 06, 2009, 08:33:39 PM
I've always had my antenna mounted in the loft with good results.  See previous discussion at http://www.airnavsystems.com/forum/index.php?topic=2528.msg21836#msg21836

My roof construction is concrete tiles over sarking and breeze-block gable ends.  The tiles cause little problem, but the gable end walls limit reception in those directions.
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: atcukmatty on June 06, 2009, 08:44:24 PM
thanks for reply tarbat. when you say 'antenna kit' are you talking about the one supplied with the radarbox.

i see your polar diagram but whats the comparison like when its not in the loft?
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: tarbat on June 06, 2009, 08:58:24 PM
The "antenna kit" is the external antenna and pre-amp and cable kit available from Airnav.   For a comparison of standard antenna vs. the antenna kit in the loft, see http://www.airnavsystems.com/forum/index.php?topic=1650.msg12949#msg12949
http://www.airnavsystems.com/forum/index.php?topic=1302.msg10765#msg10765

Sorry, I've never run with an external antenna, it's always been in the loft.
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: EMA on June 06, 2009, 09:11:59 PM
I use a loft mounted whip, from my location Derby/Notts my polar diagram goes as far north as Glasgow and as far south as the French coast. East/West is more limited due to high trees, I did have an external antenna but found little difference so had it removed after a local ligthning strike
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: EGNXR on June 06, 2009, 10:01:07 PM
Quote from: atcukmatty on June 06, 2009, 07:30:30 PM
Hi, was wondering if anyone had put the antenna that is supplied with radarbox in the loft.... if so did it make much difference?

i am on the 2nd floor of my house and wondering if i raised the antenna another 20 foot higher to loft would it make much difference?

thanks

Hi,

1st image is standard aerial outside at gutter hieght.
2nd image is standard aerial in loft.
3rd image is an 1105c at chimney height this is about the same as the standard aerial at full stretch of the supplied cable its just mounted a little less precariously due to to the longer run of cable supplied.

hope this gives you a reasonable comparison

Cheers John
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: atcukmatty on June 06, 2009, 10:27:22 PM
thanks EGNXR, interesting results there.
In the second image (loft) is that the tiles which are making attenuation north and south. east and west seem to have a fairly good range
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: EGNXR on June 06, 2009, 10:37:23 PM
Hi atcukmatty,

North south is the end brick walls- east west is through the tiles
The house runs 330-150 deg along its length if that makes sense in the polar diagrams tiled roof faces 60-240deg

HTH Cheers John
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: bearcat on June 07, 2009, 01:16:22 PM
Hi
Below is a screnshot with my supplied antenna in the loft connected by 20mtr of W103 with no pre-amps. I just tried different positions to get the best results. My range to the north west is limited a bit due to the chimmney breast.

Regards

Stewart
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: bratters on June 07, 2009, 04:38:26 PM
I tried it with the supplied aerial but the results were poor with a considerable loss of flights due to both length of aerial cable and roof tiles.

The majority of my traffic is south, so I am satisfied to concentrate on that direction and resist the temptation to sacrifice some of that traffic for odds and ends from elsewhere.

Essentially I've got 180 degrees and that's fine.
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: imropes on June 12, 2009, 04:48:15 PM
Made a massive difference to me. Icould not get the aeriel to a window (comp cant be moved) I put it originaly on top of door pick up was poor (old building solid walls) I put rb in small wire basket at top of door which gave me a bit more coax to play with.Its half way up to roof apex and its fantastic. Max range to the east. Give it a go.
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: t1mb0 on June 12, 2009, 05:01:40 PM
indeed the answer is 'suck it and see'.
Initially get your laptop(or pc) up in the loft with it, (obvious really if you want to test the bundled antenna)
Then, long term I would think about getting a 'USB Extender' (don't pay any more than £20) this will 'convert' USB to CAT5 network cable(mine is 25m from Office room to loft).
Doing it this way will ensure your losses are kept to a minimum by having as short a length of coax as possible.
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: ENKB on June 13, 2009, 02:03:54 PM
I installed the Radar box AND computer up in the loft, using VNC wiever and Team Wiever to access it from the living room or office.
Title: Re: Has anyone put supplied aerial in loft? results?
Post by: atcukmatty on June 13, 2009, 04:13:51 PM
i got a 5m usb extender it was £2. keeping the radarbox on a shelf close to ceiling. then putting hole in the ceiling and putting the aerial through the hole.

does it matter what type of usb extender? will it effect preformance

cheers