LiveATC Discussion Forums

Air Traffic Monitoring => Feed Setup Pictures => Topic started by: KevinK on February 27, 2006, 05:56:13 AM

Title: Setup?
Post by: KevinK on February 27, 2006, 05:56:13 AM
Ok, well this seems like the most appropriate place to post so... I am about 5 nm away for KEUG in Eugene Oregon. I would like to get a feed going their. What is a cheap way to go? I have been looking at icom, and does the scanner have to be specific for "computers" for it to be able to connect to my soundcard? Whats a good "CHEAP" way to go :D I want a handheld for flying, so im getting that soon. But i have a feeling that wont get the job done, because of what i have been hearing about the quality. If i can get it to worke efficiently, then sure! I live on a hill up from the Airport. So i think i might have an easier time then some picking up tower. I know ill need an antenna, but it has to be discrete. Like, an antenna that i can just hang on the side of the house that doesn't stick out all over the place! What other equipement is needed for it to work, radio wise i mean... Theirs the scanner, antenna, what else? Can the scanner just "hook" into the computer and can the antenna just hook into the scanner? Please explain. Their wasn't much info on this around the site, and yes i already looked in faq, so try to help me out guys! Im sure you all didn't go blow hundreds of hundreds of bucks right off the bat!
Title: Setup?
Post by: Kalpazan on February 27, 2006, 10:43:10 AM
I can only speak for myself but I believe it is not much of a difference for the others...

It is all not too expensive if you do not go for some very special setup. The scanner must have the aviation band and that is the only requirement for it. My one is Uniden UBC180XLT, paid around $150 at the time I bought it, it is handheld and it works just fine. The antenna I made myself but it should not cost more than $50-80 for you. Then just any PC that runs Windows or Linux and has sound card on it is fine. I bought dedicated second-hand notebook so that I can run the feed without occupying my 'mainframe' computer :-)

That's all of it. You connect the antenna to the scanner with a coaxial cable and the scanner to the sound card with a regular audio cable. Software to stream is provided to you for free. There is of course more work until u get best of it, like installing the antenna on a suitable place, proper wiring of the cables, scanner tuning, audio card adjustment and so on but those u should not be afraid of as we will help you :-)

Hope this helps...  :wink:
Title: Setup?
Post by: KevinK on February 27, 2006, 06:16:40 PM
Mk ok thats real helpful. I want the sp-200, err the nav and com on sportys. Anyone know how the quality is for feeding? The faq said they tend to sound crappy, but we'll see. What kind of antenna is it...Where are places you mount it?
Title: Setup?
Post by: Kalpazan on February 28, 2006, 12:42:21 AM
Usually you need discone type of antenna. One of these for example:

http://www.nevadaradio.co.uk/acatalog/scanmaster-antennas.html

And you mount it outside and as high as possible. Somewhere on the roof for example. But must not be too far away from the scanner to avoid signal loss.
Title: Setup?
Post by: Lezam on February 28, 2006, 09:06:29 PM
I did it a cheap way... I have a pro 83, got it on ebay new for 40 bucks. Got a jpole antenna for 27 bucks, if you want the link to the site ask me. And some RG-6 cable for free, some nice guy in radioshack paid for it (ran out of money)  :) . I have a special feed computer, wont be too hard for you to find a win 98+ computer. My mini 9 inch, 10 year old monitor :) And surge protector! Thats what I did :)
Title: Setup?
Post by: KevinK on March 01, 2006, 01:02:15 AM
Haha well i have the computer easily at my grasp "I know some people" :) I want the 200 also just for my future in aviation, althoguh that means the thing wont be up all the time but... Anyhow, any good antennas recommended? I dont think that the height will be a problem, cuz i can put it close to the roof, But!!! IT HAS TO BE DISCREET!
Title: Setup?
Post by: Lezam on March 01, 2006, 07:10:12 PM
This is the one I got, it will become discreet soon :) Its copper, and when outside it will turn brownish, so it will blend in.
http://www.kb9vbr.com/jpole.htm
If you need any help, IM me...
Title: Setup?
Post by: n57flyguy on March 02, 2006, 07:47:29 AM
I want to set up a feed of ILG in the few years before college. I hope on purchasing a Bearcat scanner by next fall. I have a couple questions. How do I hook it up to my computer? I can get an antenna and put it on my roof or back trees somewhere, knowone really cares around me, I  could just say its TV. Now what cable do I need to hook up the scanner to the antenna? How do you run it from the inside to my roof? any help will be appreciated.
Title: Setup?
Post by: Lezam on March 02, 2006, 07:16:34 PM
Its simple to hook it up to your computer. All you do is get a 2 male end headphone style cable, and hook it into your line in port.

Get an antenna :)

I use RG-6 cable, works just fine for me, but you  might want to buy RG-8, 20 bucks at radioshack.

YOu can run it through the wall, just drill a hole!

Quote from: n57flyguy
I want to set up a feed of ILG in the few years before college. I hope on purchasing a Bearcat scanner by next fall. I have a couple questions. How do I hook it up to my computer? I can get an antenna and put it on my roof or back trees somewhere, knowone really cares around me, I  could just say its TV. Now what cable do I need to hook up the scanner to the antenna? How do you run it from the inside to my roof? any help will be appreciated.
Title: Setup?
Post by: Jason on March 02, 2006, 07:21:34 PM
Quote from: Lezam
I use RG-6 cable, works just fine for me, but you  might want to buy RG-8, 20 bucks at radioshack.


Are you sure you're using RG6?  RG6 is 75 ohm cable, whereas RG8 is 50 ohm.
Title: Setup?
Post by: Lezam on March 02, 2006, 07:26:09 PM
Quote from: Jason
Quote from: Lezam
I use RG-6 cable, works just fine for me, but you  might want to buy RG-8, 20 bucks at radioshack.


Are you sure you're using RG6?  RG6 is 75 ohm cable, whereas RG8 is 50 ohm.


yup, I was told RG-8 is best for transmitting, and RG-6 is better for receiving. The guy bought it for me anyways :) I live so close to the airport, and get such good reception, that I doubt it will make that much of a difference...
Title: Setup?
Post by: n57flyguy on March 03, 2006, 06:49:18 AM
Alright, but now I need another internet connection, and thats going to take too long. I'll still see what I can do, thanks for helping me out.
Title: Setup?
Post by: Lezam on March 03, 2006, 08:03:31 AM
Quote from: n57flyguy
Alright, but now I need another internet connection, and thats going to take too long. I'll still see what I can do, thanks for helping me out.


If you have one, you could use it :)
Title: Setup?
Post by: n57flyguy on March 03, 2006, 10:06:45 AM
I do but its a bad location for a scanner to get reception from an antenna. And it is unreliable sometimes, it wirless and really sucks sometimes. I would doubt my bad fells like hearing numbers all day to (music to me). I'll talk to him and see If I could work somthing out. I really would like to set up ILG and put N57 up to. ILG has got some great operations.
Title: Setup?
Post by: Lezam on March 03, 2006, 10:08:14 AM
Do you get any reception from it? MAybe when you get a new antenna... Also, your dad wont hear a thing :)
Title: Setup?
Post by: n57flyguy on March 05, 2006, 11:28:45 AM
I told my dad, he wont care, so now it just goes back to time and money. When I told him I need to build an antenna, he just looked at me, I thought it was pretty funny, but If I have resources, Ill set up ILG if all goes well.
Title: Setup?
Post by: Lezam on March 05, 2006, 01:29:35 PM
if ya need any help, this is the place to ask :)
Title: Setup?
Post by: n57flyguy on March 05, 2006, 02:26:37 PM
I will ask, because I will need help, to start I need to get a scanner. How much do those cables cost? How much will I need?
I am figuring running a wire from a table where my computer is to my computer and another cable out to the antenna that Ill build. To get the best reception Im going to have to build it high and mount it a bit discretly so questions dont come up. That my plan for now so Ill get back to you for more help, thanks.
Title: Setup?
Post by: Lezam on March 05, 2006, 02:28:26 PM
Which? Coax? If yes, they run about 20 bucks for a 50 footer at radioshack...
Title: Setup?
Post by: n57flyguy on March 05, 2006, 02:30:35 PM
Yeah, Im going to need a bit more than that. Kind of stupid q, but can you attach more than one?
Title: Setup?
Post by: Lezam on March 05, 2006, 02:40:15 PM
Sure can, but I would reccomend getting a longer cable :) You would prob want a RG-8 50 ohm low loss cable. Longer the cable, more loss...
Title: Setup?
Post by: n57flyguy on March 05, 2006, 02:57:00 PM
Thats what i figured. How do I get it Through my house?
Title: Setup?
Post by: Lezam on March 05, 2006, 02:58:08 PM
Drill a hole in the wall?  :lol:  :roll:
Title: Setup?
Post by: n57flyguy on March 05, 2006, 03:00:47 PM
See, that wont go through my dad, but it will go throught he wall!!!!HAHAHHA. Ill see what I can do. Here is the scanner I want...
http://cgi.ebay.com/BC350C-UNIDEN-BEARCAT-POLICE-SCANNER-100-Channels-BC350_W0QQitemZ5873222289QQcategoryZ3281QQrdZ1QQcmdZViewItem

sorry for that long link, brand new 100 bucks, not bad.
Title: Setup?
Post by: Lezam on March 05, 2006, 03:02:46 PM
On that listing, if its suck a good price, why didnt anyone buy it yet :) I dont know alot about desktop scanners, but I do know a deal about handhelds...
Title: Setup?
Post by: n57flyguy on March 06, 2006, 06:46:37 AM
That scanner looks pretty much what I want, and isnt a burn and crash, then get shot on your wallet deal. I dont know much about handhelds, I think Ill just get the Bearcat.
Title: Setup?
Post by: Lezam on March 06, 2006, 07:12:59 AM
I hear bearcats are good also. I found out about all this scanner stuff by going to radioreference forums...  :lol:
Title: Setup?
Post by: n57flyguy on March 06, 2006, 10:00:16 AM
cool, Ill check it out.  

Getting my drill ready!!!! Actually there must be a way to get around drilling a hole in the wall, I'll figure something out.
Title: Setup?
Post by: Kalpazan on March 06, 2006, 12:05:12 PM
You will never become master-blaster feeder unless you drill hole in your wall  :D  :wink:
Title: Setup?
Post by: Fryy on March 06, 2006, 04:58:27 PM
Just a suggestion, check out ebay for scanners, they have alot. I got a Bearcat BC235XLT for 70 bucks, normally it goes for around 200.
Title: Setup?
Post by: n57flyguy on March 06, 2006, 09:09:57 PM
Yeah, ebay is great, thats where Im going to pick mine up.
Title: Setup?
Post by: Lezam on March 07, 2006, 06:55:05 PM
Got mine from Ebay too. BTW I am not sure you can get around drilling a hole in the wall. If you figure a way, let me in on it :)
Title: Setup?
Post by: n57flyguy on March 07, 2006, 09:16:27 PM
Will do my freind, I come up with some creative stuff so far :D
Title: Setup?
Post by: KevinK on March 08, 2006, 03:36:57 AM
Thanks guys, this helps alot! Still confused though, if i use my sporties radio instead of a scanner, how will or how much will the quality differ?
Title: Setup?
Post by: Biff on March 08, 2006, 12:41:52 PM
Quote from: Lezam
BTW I am not sure you can get around drilling a hole in the wall. If you figure a way, let me in on it :)


Do what I did: drill a hole in the ceiling.  ;)
Title: Setup?
Post by: n57flyguy on March 08, 2006, 04:39:44 PM
no drilling!!! well, I cant drill a hole so I have to figure something out.
Title: Setup?
Post by: Lezam on March 08, 2006, 06:47:20 PM
You put your antenna on the roof, but I am not going on top of my roof hehe :):) Scared lol
Title: Setup?
Post by: n57flyguy on March 09, 2006, 10:08:41 AM
It should get great reception if I put it on my roof. Why would you be to scared at most it should take 20 min to set up. Get a friend to help you out.
Title: Setup?
Post by: FlyCMI on March 09, 2006, 09:25:21 PM
Now my antenna was scary to put up, I never want to have to do that again.
Title: Setup?
Post by: Lezam on March 11, 2006, 11:31:35 PM
I am planning on putting my antenna on the side of my chimney, as high up as my 10 foot ladder can go :) So figure 10 ft + 6 ft, so about 16 feet in the air. I dont want to get on my roof, its scary up there, especially with all the wind around my house :)
Title: Setup?
Post by: Jason on March 13, 2006, 12:55:35 PM
Quote from: n57flyguy
It should get great reception if I put it on my roof. Why would you be to scared at most it should take 20 min to set up. Get a friend to help you out.


Good suggestions, Paul.  I'm sure there are plenty of friends and others in the area that would be happy to help you setup the antenna, Lezam.  Do as much as you can before actually getting up to install it.  You can get many things ready in advance.

Even putting the antenna a few feet inward on a side of a roof instead of high up in the middle will boost reception in most cases.  The more height, the better, but try not to get caught in a situation you don't want to be in.  

Also--try and stay away from putting the copper J-pole next to a copper roof at all costs.  I lost my N90 reception by doing that, so I have to revert to the discone antenna in the attic for those frequencies.
Title: Setup?
Post by: Lezam on March 13, 2006, 01:40:02 PM
I am not sure if I can actually do that though. My house is pretty old, and I am not sure if it can take my weight on it. I might be having my roofing done in the summer, so if I do I will move the antenna upward. For now, I am going to be putting my antenna as high up as I can go. Except for a tree, there is nothing visually stopping my view from jfk. So I think I will be allright with the antenna situated there, facing jfk.
Title: Setup?
Post by: KevinK on March 13, 2006, 02:43:54 PM
Question, someone was telling me that you have to get permission from the airport to monitor the freqs....that true? Also, can someone still answer my question, how well with a 2 m jpole will a sporties handheld radio put out, and how will the quality be
Title: Setup?
Post by: Lezam on March 13, 2006, 02:56:48 PM
Only in the UK you need permission, as to what I heard...


I have a Jpole, with a sportie, and it works great for me :)
Depends how far away you are, because they are low power..
Title: Setup?
Post by: Jason on March 13, 2006, 03:10:37 PM
Quote from: KevinK
Question, someone was telling me that you have to get permission from the airport to monitor the freqs....that true?


I believe that someone was referring to UK regulations as Lezam stated.

Quote from: KevinK
Also, can someone still answer my question, how well with a 2 m jpole will a sporties handheld radio put out, and how will the quality be


Are you referring to a 2 meter copper J-pole?  ...or a simple roll-up J-pole?

I don't see the purpose of using a copper J-pole with a handheld unless you use that handheld like a base station.  I can't imagine a person sitting at the airport with a sporty's handheld leaning on his ~70cm long copper J-pole (roughly 2.25 feet) antenna, but I'm not saying you can't (although I'd like to see the picture :lol:)

It is very dependant on the transmitters, their power output, surrounding terrain, and distance from the transmitter.  VHF is line-of-sight, so pilots (being in the sky; above you) shouldn't be hard to receive in most cases, but ATC facility's low-power transmitters that are either obscured by terrain or are low-power transmitters will make it difficult to receive the controller side of the converstation.

Please clarify on which J-pole you're referring to and possibly including the purpose/use that you're trying to achieve (ie: Listening from home, at the airport, etc, etc) so we can answer your question(s) further. :D

Jason
Title: Setup?
Post by: KevinK on March 13, 2006, 03:20:28 PM
I want to be able to feed it from home. Im on a hill, about 5 nm from the airport. Or maybe a bit less, someone suggested this: http://www.kb9vbr.com/jpole.htm

Its cheap and DISCRETE so thats why i wanted to buy it. If you have any other ideas for the antenna, im all ears!
Title: Setup?
Post by: Lezam on March 13, 2006, 03:26:22 PM
Quote from: KevinK
I want to be able to feed it from home. Im on a hill, about 5 nm from the airport. Or maybe a bit less, someone suggested this: http://www.kb9vbr.com/jpole.htm

Its cheap and DISCRETE so thats why i wanted to buy it. If you have any other ideas for the antenna, im all ears!


Thats my idea :) I just bought one, and so far, for the price... Its doin pretty good! You can paint that to be any color you want too...
Title: Setup?
Post by: KevinK on March 13, 2006, 06:12:16 PM
How did you mount it?
Title: Setup?
Post by: Lezam on March 14, 2006, 01:06:31 AM
I didnt mount it yet :) I drilled the hole through the wall, and I have to go to home depot to get some lag shields and bolts :)
Title: Setup?
Post by: KevinK on March 14, 2006, 03:04:46 AM
Hmm, what are you using for your reciever?
Title: Setup?
Post by: Lezam on March 14, 2006, 09:20:31 AM
I am using a little pro-83 from radioshack (Similar to the bearcats, but cheaper) Doesnt give out alot of power, but I am so close to the airport, it prob doesnt even matter :)
Title: Setup?
Post by: KevinK on March 14, 2006, 02:42:50 PM
Mk, but yeah also will their be a huge difference in the quality of the sound of the feed with a handheld, compared to a scanner?
Title: Setup?
Post by: Lezam on March 14, 2006, 11:47:46 PM
Quote from: KevinK
Mk, but yeah also will their be a huge difference in the quality of the sound of the feed with a handheld, compared to a scanner?


No clue... Anyone?
Title: Setup?
Post by: KevinK on March 15, 2006, 03:14:09 AM
Btw LEZAM, this is a bit random, looked at your link, your not hiring any web designers are you? I have about 4 years experience, knowledgable in HTML,Javascript,Some CSS,PHP, Learning asp, and yup!
Title: Setup?
Post by: Lezam on March 15, 2006, 08:27:20 AM
Yep, I am actually hiring, check your PM.
Title: Setup?
Post by: KevinK on March 16, 2006, 02:42:46 PM
Replied, anyhow, anyone know about the quality?
Title: Setup?
Post by: Lezam on March 16, 2006, 02:51:41 PM
Personally, I would go with the desktop, because it sits up on the desk, unlike the handheld, and it prob has more functions then handheld. I like my radioshack handheld, because I can take it around with me, but if you dont need to take it around :) go with desktop
Title: Setup?
Post by: KevinK on March 17, 2006, 03:08:40 PM
Well i need a handheld because im starting flight training in the summer. Dont really want to have to pay for the scanner if i dont need it
Title: Setup?
Post by: Lezam on March 17, 2006, 03:24:34 PM
Awesome, go for the handheld :) I personally like radioshack...
Title: Setup?
Post by: Fra on March 21, 2006, 12:05:56 PM
Hi guys, I have a question about the antena. Well, I live in a 8 floors tall building, and I live on the 5th. I plan on placing the antenna on the top of my building, and than connect it with a cable to my appartment. What kind a cable to I need and will it be trouble the distance for the scaner?
Title: Setup?
Post by: Lezam on March 21, 2006, 02:38:02 PM
Would you say thats about 50 feet?
Title: Setup?
Post by: Fra on March 21, 2006, 05:48:18 PM
Quote from: Lezam
Would you say thats about 50 feet?


The building's height is 78 feet so yeah, 50 feet should do it till my balcony or something. I also wondered, there is a high mountain between me and the airport, you think that will interfere with the waves?
Title: Setup?
Post by: Lezam on March 21, 2006, 06:15:07 PM
You need 50 OHM, or 75 OHM cabling. You can pick it up at radioshack. I bought RG-6, but you might want RG-8.

The mountain will effect the quality, but you might be high enough to not notice it :)
Title: Setup?
Post by: Fra on March 21, 2006, 06:19:05 PM
So 75 OHM would be better, right? I need to look up the height of the mountain, but first I need to get a good scaner. (I have no idea about scaners). The thing is that here they are hard to get (few people are using them) I know 2 guys that perhaps own but I need to ask them. Anyway, if I can't find any to buy, I'll order one from Germany or even USA, I have lots of friend that would buy from ebay and send it. In few days I should get internet link and start preparations, so for now I'm still picking up informations.
Title: Setup?
Post by: Jason on March 21, 2006, 06:20:54 PM
Quote from: Fra
So 75 OHM would be better, right? I need to look up the height of the mountain, but first I need to get a good scaner. (I have no idea about scaners). The thing is that here they are hard to get (few people are using them) I know 2 guys that perhaps own but I need to ask them. Anyway, if I can't find any to buy, I'll order one from Germany or even USA, I have lots of friend that would buy from ebay and send it. In few days I should get internet link and start preparations, so for now I'm still picking up informations.


I'd suggest picking up 50 Ohm coax.  For the long distance you are talking about the coax traveling from the antenna to the scanner, try and get some very well shielded coax like RG-8/U or Belden 9913.

Jason
Title: Setup?
Post by: Lezam on March 21, 2006, 06:22:23 PM
Yup, 50 OHM would be best for you. Where are you located anyways? Sometimes you could find good auctions on ebay that include worldwide shipping prices :)
Title: Setup?
Post by: Fra on March 21, 2006, 06:27:34 PM
Right now, Ohrid Macedonia

I sure will look things up, first I need to solve the internet connection, than to find a suitable pc (I have a very old one that I don't use 166 mhz, 16 mb ram, 700 mb HDD) but I don't think this would work, so I need to buy something second hand, or who knows, it has win98 on it (I'd prefer linux, so I'll try that one too, than the antenna (have no idea about this) than comes the tricky part (the cables scaner and to wire the whole thing up) Step by step.
Title: Setup?
Post by: Lezam on March 21, 2006, 06:32:29 PM
Wow, what country is that:)
Title: Setup?
Post by: Fra on March 21, 2006, 06:34:23 PM
Located in the Balkan peninsula, east of Italy and Albania, north of Greece.  :)
Title: Setup?
Post by: Lezam on March 21, 2006, 06:36:37 PM
Quote from: Fra
Located in the Balkan peninsula, east of Italy and Albania, north of Greece.  :)


I am guessing they dont have a radioshack up there :)
Title: Setup?
Post by: Fra on March 21, 2006, 06:43:59 PM
No radioshack :( I should have bought long time ago, it just never crossed my mind. I will pull it out somehow.
Title: Setup?
Post by: Lezam on March 21, 2006, 06:45:32 PM
Well, you guys have credit cards up there right? You could make an ebay account, pay for it via paypal, and have it shipped to you from another country I guess...
Title: Setup?
Post by: Fra on March 21, 2006, 06:51:10 PM
Yeah, but I don't really know if ebay ships internationally. Few years ago, while I was living in the states it was us and canada only, so I dont know right now if they do it.
Title: Setup?
Post by: Lezam on March 21, 2006, 06:52:21 PM
Well, ebay doesnt ship themselves. Some auctions have a "worldwide" shipping rate, flat for any country. I am sure that if you got a ebay and paypal account you could get it shipped to you. Its just a matter of cost.
Title: How to buy and pay
Post by: leonardoperezsalles on May 03, 2006, 10:01:32 PM
Dude, i live in Honduras and although we have Radioshack they radiosuck cuz they dont sell all the neat things they sell in the US, and the postal service is a mess. But there are some companies that that a service called an IMC-International Mail club, this means that the company rents or buys a PO BOX in the US and they sub-lease it to you and bring the packages from the US to my home. So that gives you the ability to have an address is the US and so on...I Bought my Uniden BC895XLT that way.
Title: Setup?
Post by: KevinK on May 09, 2006, 03:03:47 AM
Its been awhile since ive been here, lost interest for awhile, but got it back. Im looking to buy the Sporties sp-200 as mentioned previously, although i would like a cheaper option, but im also going to start flight training, so i need a radio that will preform proficiently 100% of the time.

Anyways, so my location is like this. The airport is in a flat valley, maybe 5-6 nm away, abit closer possibly. Im on top of the hill, on a 45 degree side from the airport So its like this. The airport is north in the valley, this hill is south, and im on the east side, but very close to top. Theirs no hills inbetween me and the airport,so i think i should possibly with the right antenna havesome good luck. Im still confused onthe difference between the Jpole, and a Dupole, what OHM cable to get etc. I know nothing about that stuff, so thats why im here :) What do you guys think  i should use for the setup in regards to that? Ill still leave the market open for cheaper Handhelds, but i dunno. Only problem, is that the charger for that thing is another 100 bucks, i mean like a 9c charger, lol this is more expensive then i was told *rolls eyes*. Let me know! Anyone using the sporties sp-200 by chance?
Title: Setup?
Post by: KevinK on May 10, 2006, 10:24:17 PM
Oooh, talked to my dad, i guess im a bit further. Im about 7 nm from the airport. Lol how big of antenna am i gunna need if im on a hill?
Title: antennas
Post by: kmzairdetail on May 14, 2006, 04:31:49 PM
First question. Whats the best anenna? Jpole or discone? And if I did venture into trying to craft a jpole, how do I tune it?
Title: Re: antennas
Post by: Jason on May 14, 2006, 04:43:46 PM
Quote from: kmzairdetail
First question. Whats the best anenna? Jpole or discone? And if I did venture into trying to craft a jpole, how do I tune it?
Firstly, welcome to LiveATC.net!

Secondly, Check out this link: http://fordyce.org/scanning/scanning_info/scanant.html  It has a great mini-article on different antennas.

The copper J-pole has about 3dB's of gain whereas the discone has 0 (zero).  It really depends on your circumstances/situation.  Check out this thread for more details on the J-pole and how to build one: http://www.liveatc.net/forum/viewtopic.php?t=1491

As to tuning the j-pole, you tune the J-pole by the measurements you build by (See the above linked, thread).

Hope this helps,