Liveatc EIDW feeder needs better antenna

Mech1

Advise needed, I have already posted here http://www.boards.ie/vbulletin/showthread.php?t=2056967147

So I dont wanna double post if its not allowed.

Thanks,
Pat

...__...

vhf quad would be ideal you could build one yourself for a few euro.
but the commercial airband antennas would be your best bet
http://www.wsplc.com/acatalog/Airband_antennas.html

...__...

by the way thank you for feeding not often you get to thank the person who provides the service.

brownmini

Mech1 wrote: »

Advise needed, I have already posted here http://www.boards.ie/vbulletin/showthread.php?t=2056967147

So I dont wanna double post if its not allowed.

Thanks,
Pat

Suggest a J-pole cut for the centre frequency of the frequencies you are interested in (within reason- the J-pole is not a broadband aerial)
Easier to mount.
Stronger.
Less bits to catch wind in a storm
Can be home-made.
Measurements at: http://www.hamuniverse.com/jpole.html

73


follow-up at 2120 11th june 2013

If you enter the words below into google - you'll get a lorry load of pictures
of what a J-pole looks like and many of them are homemade one so you'll get
the idea on how to tackle your own version.
The words are . . . . . . . . pictures of j-pole antenna


But remember, that the measurements given in most of these pictures
will be for 144MHZ and not 122 MHZ so use the calculator at
http://www.hamuniverse.com/jpole.html
to calculate the dimensions for 122MHZ or where you want.
At 122MHZ - the aerial will be bigger than one for 144MHZ.

73

Mech1

I gave up on the "home build antenna", not enough spare time.
Today I ordered a D-777 antenna from Martin Lynch & sons in the uk.
Anything I should be aware of when installing? I see people are making coax loops, some type of choke idea?
Do i need to do this if im not transmitting?
Should I run a ground lead to the antenna?
Amplifier?
pl259 to rg213, What size (wattage) soldering iron needed to do it right? Previously I have had problems with the connector plastic melting before the solder runs.

Replacing this http://i962.photobucket.com/albums/ae101/mech1111/IMG_0517.jpg Discone plus another 1.5M higher mounting pole.

All tips welcome, click on my sig link to hear it now, Static messing with 121.100 Approach especially.

Thanks.

ps. Watty I know your the Antenna expert from reading your posts on here over the years. I would love it if you could listen to the feed and comment before and after D-777 instalation.

martinsvi

Coax chokes are to avoid RF current getting back to the rig. Since you're not going to be transmitting, you don't need that.
Ground (earth) lead is a good idea in case if there are no lightning rods or tall trees close by. You don't want to invite a fire hazard at your home. If there is a good lightning rod (conductor) close, you can live without.

I wouldn't use an amp - since the feed is good already, you will just invite more interference and static, I think..

Mech1

martinsvi wrote: »

Coax chokes are to avoid RF current getting back to the rig. Since you're not going to be transmitting, you don't need that.
Ground (earth) lead is a good idea in case if there are no lightning rods or tall trees close by. You don't want to invite a fire hazard at your home. If there is a good lightning rod (conductor) close, you can live without.

I wouldn't use an amp - since the feed is good already, you will just invite more interference and static, I think..

Thanks, why do you think the "static" is present more on 121.100 than other close freq that are crystal clear?

I'm hoping that its the "broad spectrum design" of the Discone thats picking up interference around that freq and that the d-777 will be immune.

martinsvi

I can only speculate, but if I remember correctly, static is even present next to airport. Maybe they use an antenna with a slightly different radiation angle or maybe they are directional, as all approach patterns are predefined..

Mech1

yeah I thought the problem must be on their side, cutbacks and such I suppose:D

Mech1

Up and running on the D-777 antenna now, big improvement.

http://http://www.liveatc.net/search/?icao=eidw