Not enough space for a good antenna to listen...

[Intersoundradio]

One of the best antennas you can get in this situation... "Now days my interests are shortwave broadcast listening, pirate, clandestine, number stations. The dark side of radio, if you will. I think the equipment is ok. My issue is more with antennas. I have a bit of space but not huge. ¾ acre. No legal or neighbor issues. I can’t afford a tower and have no real way to get very high up in the air."... is the active receiving loop antenna:

http://pa0fri.home.xs4all.nl/Ant/Active%20antenna/Active%20receiving%20%20loop%20antenna%20eng.htm

[redhat]

Interesting bit, although the amplifier IC he is using is 50 ohm input, and most loop preamplifiers are HiZ input, as the loop in no way represents a 50 ohm source, except at higher frequencies.

Just my two ¢

+-RH

[jFarley]

The link you posted represents a good approach to a simple shielded non-resonant loop design. 

Another design is detailed here: http://www.lz1aq.signacor.com/docs/wsml/wideband-active-sm-loop-antenna.htm

His home page contains links to additional info: http://www.lz1aq.signacor.com/

[Intersoundradio]

Thank you for your reactions. I appreciate it very much.
A different type of antenna for little space is the "Mini-Whip active antenna". It has nothing to do with the loop, but this type of antenna is even smaller in size and works also very well! Bandwidth is 10 kHz to 30 MHz.
The WebSDR Twente in the Netherlands use one and achieve very good reception results with it: http://websdr.ewi.utwente.nl:8901/
More information about this Mini-Whip antenna:
http://www.chirio.com/mini_whip_e.htm
and http://dl1dbc.net/SAQ/miniwhip.html (open also on the bottom of this page [1], [2] and [3] for more information).
You can buy the mini-whip very cheap as a KIT in several shops, like here in the Netherlands by Van Dijken Electronica http://www.vandijkenelektronica.nl/main.php?action=product&categories_id=0&products_id=3086, but it's also easy to made it by yourself http://priyom.org/articles/antennas/pa0rdt-antenna-(mini-whip).aspx 

Youtube-information in three parts...
http://www.youtube.com/watch?v=PXbwGAhSgtg
http://www.youtube.com/watch?v=MaqimJk5VeU
http://www.youtube.com/watch?v=A4fn7p3J2E0

[skeezix]

Built a PA0RDT mini-whip here. It works fine, esp on the lower part of the spectrum but it does need to get away from electrical noise sources.

[Intersoundradio]

That's right. The best way is to hang the mini-whip not to close by your house and electrical noise sources. In that way is the mini-whip much more sensitive to interference than the loop antenna... But the loop antenna works directional. So you can turn the loop away from the source of interference. Hopefully is that not the point where you get the received radiostation at his best...

I apologize for my bad English. It's not the most easy way for me, because I come from the Netherlands, but I try to do my best, haha.

[CoolAM Radio]

Hello Hans!

First time I see you in HF Underground! Nice to see you here!

You forgot to mention (lol) the Mobile Super Antenna I'm using - also because of
(more-) limited space! (installed on balcony!)
It's the  SIGMA PLC-45  (length = about 135 cm) originally it's for use 6600-6700 - but with only small modification(s) -
It's useable from 40 to 52 meters - only get from a metalstore a stainless steel - pin - replace the original with this new one
and adjust swr  for the frequency you wanna use!
Be Carefull  only for Max. 50 watts!!!
http://www.coolam.nl/plc45.pdf

Short clip of the PLC45 on my balcony
http://www.coolam.nl/coolam-2013.avi

Greetz

André
CoolAM Radio - ShortWave 6735
http://www.coolam.nl
the Netherlands

[Intersoundradio]

Haha, that's right, Dré! I forgot your SIGMA PLC-45 antenna, which is also fine for transmitting! The whip is, of course, only for receiving and the loop works better to receive than to transmit.

Also nice to meet you here, Dré!