RadioReference on Facebook   RadioReference on Twitter   RadioReference Blog
 

Go Back   The RadioReference.com Forums > HF / MW / LW Monitoring > Receive Antennas (below 30MHz)


Receive Antennas (below 30MHz) - For all topics related to receive antennas used on HF, MW, LW, etc. For transmit antennas use the Amateur Radio Antennas forum.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1 (permalink)  
Old 04-22-2017, 3:40 PM
Member
  Amateur Radio Operator
Amateur Radio
 
Join Date: Feb 2014
Posts: 310
Default ApexRadio RX antenna

Had an opportunity this afternoon to check out the ApexRadio 303WA-2 vertical antenna. The antenna itself stands about 6' tall. It was mounted about 8' above ground and fed with 60' of RG-58.

Here are the results of a side by side comparison of this antenna with a plain 50' wire antenna. Testing was done mid-afternoon when signals are generally steadiest. RX was Satellit 750.

On shortwave, the Apex antenna gave far better performance than did the 50' wire. Time signal stations WWV on 10000 and 15000 and CHU on 7850 were many S-units higher on the Apex vertical.

Dropping down to the AM broadcast band, the results were similar. WLW 700 and WGN 720 both had nice signals on the Apex. WTVN 610 Columbus 5kw and WEOL Elyria 1kw both in OH both had S9+ signals on the Apex. All signals were only S1 on the wire.

Heading down to the LW NDB band my expectations were not that great. However, what a surprise awaited me. Performance on the 50' wire was dismal as expected, but logged 35 NDBs, many out as far as 300 miles, on the Apex...wow! This was mid-afternoon, not exactly the best time for NDB hunting.

This unobtrusive relatively small ApexRadio 303WA-2 antenna is a real winner. This would be an especially useful antenna for someone who lives in an antenna restricted space.

Last edited by WA8ZTZ; 04-22-2017 at 3:53 PM..
Reply With Quote
Sponsored links
  #2 (permalink)  
Old 04-22-2017, 4:29 PM
Wiki Admin Emeritus
  Amateur Radio Operator
Amateur Radio
 
Join Date: Jul 2002
Location: Bowie, Md.
Posts: 20,547
Default

The antenna can be seen here, via Universal Radio...

Apex Radio 303WA-2 Shortwave antenna. ApexRadio

Mike
__________________
links editor, Utility Monitoring Central
HF Forum moderator, RadioReference
Friends don't let friends buy Scancat Lite Plus!
Reply With Quote
  #3 (permalink)  
Old 04-23-2017, 10:09 AM
Member
  Amateur Radio Operator
Amateur Radio
 
Join Date: Oct 2007
Location: Lisbon MD
Posts: 304
Default

If you don't mind my asking, please describe the 50' wire you're comparing this antenna to. I'm puzzled as to how a passive antenna so short can be so much better than a 50' piece of wire.

My best guess is that you're somehow reaping the benefit from 60' of coax on it's way up to the antenna. But I'd really like to know more.
__________________
Jake Brodsky, AB3A
Reply With Quote
  #4 (permalink)  
Old 04-23-2017, 12:46 PM
Member
  Amateur Radio Operator
Amateur Radio
 
Join Date: Feb 2014
Posts: 310
Default

Quote:
Originally Posted by ab3a View Post
I'm puzzled as to how a passive antenna so short can be so much better than a 50' piece of wire.
You aren't the only one... puzzles me too. Without dissecting the base section of the antenna to see what is going on inside limits me to guessing perhaps a ferrite arrangement of some sort. Would have to be very wide banded though, look at the antenna specs... 30 kHz to 30 mHz.

Anyway, the 50' wire antenna was just that. Nothing fancy, just an insulated 16awg 50' length of wire temporarily hung up about 8' and connected to the antenna input(s) of the Satellit 750 without any coax, matching device or tuner.

Your guess about the 60' coax got me thinking as to whether it was acting as an antenna so tried the ApexRadio antenna with just a 6' length of coax into my Tecsun PL600 on various SW sigs and then compared it to the 60' length of coax into the same radio, same sigs. If anything, there was a slight loss with the 60' coax.
Reply With Quote
  #5 (permalink)  
Old 04-28-2017, 6:42 AM
Member
  Amateur Radio Operator
Amateur Radio
 
Join Date: Feb 2014
Posts: 310
Default

ab3a,

Been giving this some more thought and figure that the ApexRadio antenna must have a very efficient impedance matching transformer device in order to couple the signal very effectively into the receiver. If so, it's amazing they got it so broad banded. This is just a guess on my part as there is no antenna analyzer in my shack and those of my friends only cover 160 meters at the lowest.
Reply With Quote
Sponsored links
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 1:03 PM.


Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
All information here is Copyright 2012 by RadioReference.com LLC and Lindsay C. Blanton III.Ad Management by RedTyger
Copyright 2015 by RadioReference.com LLC Privacy Policy  |  Terms and Conditions