Antenna Query From New Radarbox User

[g0seg]

Hi again Covernotes. Don`t sound so fed up - mind you, we all go through the `gloom` stage thinking the box has gone wappy etc. If i was closer, i`d give you the ruddy cable to get you operational!! All you`re risking is a few bob for whatever satellite cable you can get hold of and cutting the supplied feeder cable for the aerial in half - that`s about it! In other words, unless you make a complete bobo of soldering the ruddy thing together it will not fail! Keep the feeder as short as possible and as high as you can get - the picture you sent of the installation of the one you made seems fine for height. One word of warning. When you solder the centre conductors together ensure it is NOT plugged into the radarbox or computer - DO NOT FORGET! Tell you what, if it doesn`t work i`ll buy you a new curlywhirly - how`s that! Bi now and give it a go! Roger - By the way, i`m knocking 70 so you have to take into consideration i might be totally gaga but i ain`t - i think!!

[g0seg]

Hi Covernotes, the attached picture is titled spot the curlywhirly! I`ve put them up where they usually are - always temporary as i`m forever pratting about with them hence the grubby look. You can clearly see the transition between the antenna coax and the satellite cable. The one with the Roses sweet box lid grounplane is a homebuild and that`s the one in use at the moment. It`s temporarily mounted on one of the groundplanes of the 2metre antenna but that one`s only used for receive airband. The other antennas for 6/2/70 are on the roof of the house. The antenna at the top of the mast is for 23 cems - 1296Mhz. Don`t forget to spray the antenna with something to protect it or it wont last very long - i use stuff called `Dampstart` - you can use ordinary varnish spray as a last resort. Good luck- wish i had your weather at the moment. Well below freezing here and we`ve got light snow again. Lived in Cyprus for years in the RAF and we had temperatures like yours - ah, turn back the clock! Bi now, Roger

[covernotes]

Inspirational stuff g0seng,
What type of satellite cable would you recommend on the curlywhirly?
I wonder whether the signal would be degraded if it was housed in a 13-14 inch length of 50mm PVC pipe with a PVC cap on the top?
Then mount it on a 5 inch diameter ground plan cut from an old aluminum pizza (as in food) dish?
The hot weather....no no no no.
Last year we got one day of 120 degrees.
Then we had the big fires with a massive loss of life.
Global warming should be called global warning.
I hope someone is listening.
Cheers
Covernotes Melbourne.

[g0seg]

Morning Covernotes. As for putting the curlywhirly in a pipe, well, i don`t know if the stuff is RF transparent - you`ll have to experiment with that one. As for the groundplane, no, it must be ferrous or you won`t get the magnet to stick. Any tin lid will do for a start as long as it`s a reasonable size but it`s not critical. Main thing is to get you operational and then you can experiment. As for the feeder, ask for the best available but use as little of it as possible. I paid 17 UK pounds for 100 metres of the stuff and although it`s not the best it does the job. Actually, i`ve been given some of the best available but havn`t got round to testing yet - we`ve got snow! As for the weather, your point taken but spent years in the warm and at my age it makes the difference. I`m very wary of this global warming business - tend to think of it as a natural phenomena/cycle. Average volcanic eruption produces more output in a day than man does in a year so i`m told - although we do get an increase in global temperatures before an ice age - and we`re due one! Bi now, have a good day. Roger, frozen Pontefract.

[ENKB]

I put both my radar box and the computer up on the loft , and running VncWiever to access the computer. Works great and i can check my RadarBox screen from ewery remote site (including cellular phone).

[covernotes]

Update on the antenna installation. The antenna (same as previous) now has an N type panel connector insitu. 3 metres of LMR400 cable from the antenna (mast head) to the RB (now situated inside the roof) 15 metres of USB cable through the roof and down to the computer. The result. 200 nm plus. From Melbourne across the border into New South Wales and also South Australia. Picking aircraft up both taking off and landing on the tarmac at Melbourne Airport. I just hope the RB can weather the Australian Summer heat in the roof. Cheers Covernotes Melbourne.

[g0seg]

Hi Covernotes, glad to hear that all is well now - bet you`re glad to have stuck it out. Regards, Roger

[covernotes]

Hi Roger, Thank you for your thoughts. Yes, I feel much happier with the result now. Though, I guess in a week or two I may well be trying to increase the antenna's performance. Regards Covernotes.

[g0seg]

Hi Covernotes, thanks for reply. Take it from me, you`ll spend the rest of your life trying to increase range etc - same in amateur radio actually - and nearly all radio hams are dedicated `got to do better` men. Bi now, Roger

[covernotes]

Hi all...In the search of the holy grail I decided to try for even better performance than I was currently getting from my home brew vertical antenna. (http://www.tech-software.net/). Not that I should complain. The home brew constantly had a range of 225 nm and constantly placed aircraft 200 feet above the runways at Melbourne Airport (YMML). I live 13.5 nm SE of Melbourne Airport.
I opted for a commercial antenna (to remain unnamed) My overall range immediately dropped by 50 nm. I immediately lost aircraft well out from Melbourne Airport, still over 1000 feet in altitude.
Needless to say the home brew antenna will be returning to its rightful position on the roof. I plan to elevate the home brew antenna another three metres and place the RB in a suitable weatherproof box on the mast.
Any advice on a suitable weatherproof box.
Cheers from Melbourne Australia, Covernotes.

[covernotes]

Hi to all.....Still in search of the holy grail. Have just roof tested the Radarama Trans-1090 Base 1090 MHz Aircraft Transponder Antenna. A real cheapy from Rocket Radio in the UK. Value for money, this is an absolute boomer. Effortlessly picking up aircraft 225nm distance. An added plus is that it is small in size and very unintrusive. I am still trying to source a masthead box suitable to house the RB. Any help would be greatly appreciated. Cheers from Covernotes, Melbourne, Australia.

[Renigade]

Hi all,
I am Renald from Malta and I am having the same problem that covernotes was experiencing. The only building screening I have is the church that is about 200 meters away from my home. My Airnav standard antenna is on the roof about 30 feet from ground level. The tracking is not very satisfactory about 50nm round. I saw the link posted at the very begining (http://www.nodomainname.co.uk/Omnicolinear/2-4collinear.htm). I am thinking of doing one like this. Do I need a pre-amp? and another question, What is the best that I connect an adapter to the Ntype female to sma and then run with an sma cable or run with a uhf cable(what is the best type?) and then an adapter to sma straight in to the radarbox?

thanks renald

[juangelb]

Hi Renigade,

I made several of the project you posted the link, obviosly calculated for 1090 MHz.
The best performance was achieved with 8 and 10 dipoles.
This works very well and does not need preamp. Recommended not tu use more than 12 meters low loss cable.

Screen-shots from two  Rbs using the aforementioned antennae :

[Renigade]

thanks :) i will try to do one and let you know with the reuslts obtained.

cheers

[steve1970]

Hello Renigade
I've had my radarbox for nearly a month.
As covernotes did I made the 1090 Mhz ADS-B Vertical Antenna (10/08/2006) too and temp mounted it to try it out. It's only fed with RG6 and patch leads ATM. I'm using a Jim M-75 pre-amp to compensate for the loss in the cable but it works well as shown in the polar image.
Just bought a BS1105 antenna but it's not going up until the cable arrives which is 7 metres of LMR400.
The homebrew antenna works well good quality cable is important (low loss)

Steve