Call Search

New to Ham Radio?
My Profile

Friends Remembered
Survey Question

DX Cluster Spots

Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement

donate to eham
   Home   Help Search  
Pages: Prev 1 2 [3]   Go Down
Author Topic: Thin wire/ "Invisible Antennas"  (Read 70216 times)

Posts: 83

« Reply #30 on: January 01, 2013, 06:40:23 PM »

Hi All-

Thank you for the response.  Just to address a few points...

1.  The configuration I was using a few months ago were thin wires that formed an off center dipole.  The wire was #24 (or #22) from radio shack (solid core) that I felt through the screen of my window.  I made effectively an off centered inverted V type dipole.  This was fed through a manual tuner and I tuned it to the usual SWR 1:1 match condition.   This dipole was just on the outside of my building, effectively running along the length of the building.  I tied off the ends by either using some string and tying to a gutter or actually wrapping the wire around the gutter (I know this is probably a horrible idea - but it was meant to be put away rapidly). 

This configuration, while not ideal, still suffered from having a lot of noise.  Some of it I think could be from the apartment.  We have also have a power transformer for the building not more than 50 feet from my operating station.  We may also just be in a noisy environment as well because there are a lot of power poles close by as well.

2. For now, I have had more success using a mag loop antenna indoors.  That has gotten me some modest QSOs, mainly on digital modes.  With it being winter, I am not keen on feeding an antenna outside at the moment.  I am also probably going to be moving fairly soon, so the indoor loops might be "good enough" for now.

3. I have seen some of you guys talk about the mfj 1025,1026, and Timewave ANC-4.  I read a little bit about their operation and it sounds like a pretty neat idea - if you can get it to work.  Would people generally recommend them?  Is there a particular type of noise they are especially well suited for?  I am thinking it might be worth a shot at least.  Given that my antenna for receive and transmit are going to be in the same room, I could see it working potentially.

4. This whole thing raises a new question that I have been wondering about.  Has anyone tried to develop software that could digitally filter out noise?  I am not so much talking about the DSP that is the radio hardware, but more of a software program that would do that?  Kind of like you would feed the audio in and then it would get filtered somehow to clean up the audio?

I only ask because at work I have used Butterworth filter to low pass some of the data that I have been analyzing.  We had high frequency "harmonics" that we wanted to eliminate from our data.  I was just wondering if something similar has been done or could be done?  I'd imagine there are some limitations or issues with these methods.

Posts: 100


« Reply #31 on: January 04, 2013, 04:05:49 PM »

I was in the local Canadian Tire store today and walked past a rack that had MIG welding wire in it. There was aluminum and copper wire. I thought to myself "wow that would make great antenna wire" (The copper) as it is pretty thin. Not sure how strong it would be. Has anyone used that wire for antennas?

It was $10 for two pounds and there has to be a lot of wire on that 2 pound spool.
Pages: Prev 1 2 [3]   Go Up
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!