shortwave indoor ant

bluefox2163 · #1 (**permalink**) 07-15-2009, 02:13 PM

hi can anyone recommend a really good shortwave antenna that I can use indoors that will really pick up the signals good....either wire or pl259 thanks!

ka3jjz · #2 (**permalink**) 07-15-2009, 02:18 PM

I will move this to our Antennas forum - in any case, a little more information is needed. What rx are you using? Do you have access to an attic? Can you hide something outside using very thin wire? (outdoor antennas are always preferable, unless you have one of those no-antenna convenants...) Do you have a porch or similar that could possibly hide an antenna?

73 Mike

CLynch7 · #3 (**permalink**) 07-15-2009, 03:34 PM

Active or passive?

bluefox2163 · #4 (**permalink**) 07-15-2009, 05:28 PM

yes I am using a AOR 7030+ reciever and cannot install any type of outside antenna,if you can recommend something thats worked very well for others,I would appreciate it

ridgescan · #5 (**permalink**) 07-15-2009, 06:47 PM

Hell in a pinch you could use a metal tape measure

just hook the end of it to the rig and extend it out as far as you can. You can tack a 30-50' length of 20 guage copper wire up by the ceiling on the wall around the room and connect a lead onto it (pushpins would work every 5')-you could run it along the baseboards too but I feel you're more likely to pick up more noise there than up by the ceiling.
C. Crane sells a Sony active antenna that basically works like that tape measure except it has a signal amplifier in line that takes a 12 volt adapter to run it.

ka3jjz · #6 (**permalink**) 07-15-2009, 07:53 PM

Again, Bluefox, more details. Do you have an attic or crawlspace? Do you have a porch (what you might be able to do is use some very thin speaker wire and wrap it a couple of times around the perimeter...)?

Indoor antennas tend to perform rather poorly against mounting that same antenna outdoors, so the further up and out you can get it, the better.

An attic is a better choice, frankly. I put a 100 foot loop up in my attic for awhile and it worked like gangbusters. The Shortwave SWL antenna group has many possible designs (it's at the end of the HF antennas wiki), and many of them use a 9:1 transformer (otherwise known as a Magnetic Longwire Balun or MLB - although it's something of a misnomer) to help keep the noise down.

If you're in an apartment (sounds like it), try to wrap as much thin wire in a loop vertically around the perimeter of an outside facing wall (inside the room, of course...). Feed it with a MLB. Making a loop like this helps keep certain kinds of noise down (that's a property most all loops share) and the MLB will help even more in this regard. The HF Antennas wiki has links for these as well, or the Yahoo group has plans if you want to build your own. Mouse over the Wiki link in the blue toolbar under the logo, click on Antennas then HF Antennas. These links are at the bottom.

Actives are nice, but they can amplify as much noise as signal, particularly if there's no gain adjustment. Sometimes you can find a 'quiet' spot if you wander around with it, but frankly, there are cheaper - and in some ways better - alternatives. 73 Mike

nickcarr · #7 (**permalink**) 07-16-2009, 01:49 AM

Any indoor antenna is going to limit what you can hear. That being said, I've seen some YouTube videos of guys with "slinky" antennas. You can go to a dollar store and buy a Slinky and un-wind it out - say across the top of your ceiling. Attach a piece of coax with aligator clips and will probably have a decent antenna.

Just don't get your expectations up... you're only going to receive very strong signals.

Check out this video: YouTube - Grundig S350DL W/Slinky Antenna

ka3jjz · #8 (**permalink**) 07-16-2009, 05:23 AM

Be careful here - make sure the Slinky is metallic. There are many plastic ones out there...and here's another type of antenna, loosely based on a helical design...

http://wiki.radioreference.com/index...er(tm)_special

And here's a pretty nice little article on active antennas from our wiki....

Active Antennas KB6RWX - The RadioReference Wiki

73 Mike

CLynch7 · #9 (**permalink**) 07-16-2009, 10:40 AM

Quote:

Originally Posted by nickcarr

Any indoor antenna is going to limit what you can hear. That being said, I've seen some YouTube videos of guys with "slinky" antennas. You can go to a dollar store and buy a Slinky and un-wind it out - say across the top of your ceiling. Attach a piece of coax with aligator clips and will probably have a decent antenna.

Just don't get your expectations up... you're only going to receive very strong signals.

Check out this video: YouTube - Grundig S350DL W/Slinky Antenna

I've had some pretty good results with a Slinky antenna dipole fed into a Rat Shack 20-280 amplified shortwave antenna. Slinkies were on the apartment balcony, radio and amp inside. Dipole config was a little quieter than end-fed longwire config.

blinddog50 · #10 (**permalink**) 07-23-2009, 04:22 PM

You can get one of those slinky antennas pretty cheap on ebay.
Just hang it in a corner of the room or someplace out of the way.
Make sure to attach a 9:1 balun to match impedence.

nickcarr · #11 (**permalink**) 07-23-2009, 04:40 PM

For SW portables, you don't need the balun really. They have high-Z terminals which essentially do the same function.

blinddog50 · #12 (**permalink**) 07-23-2009, 06:26 PM

Quote:

Originally Posted by nickcarr

For SW portables, you don't need the balun really. They have high-Z terminals which essentially do the same function.

While the AOR 7030 does have high Z terminals, I think he would be happier using a balun.
Less noise pick up IMO.
My definition of a portable is, if it can't run on batteries, it ain't portable.