Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
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
About eHam.net

donate to eham
   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: Duplexer question  (Read 775 times)
KJ4OBR
Member

Posts: 112




Ignore
« on: June 07, 2011, 09:41:14 PM »

Hi all I'm investigating a sudden increase in swr and am suspecting the comet cf-360 duplexer. I use it to split 10m to my Larsen 27nmo antenna cut for 10m fm, and divert 6m, 2m and 440 to the Maldol Ex510b.

Running the individual antennas directly to the ft8900 yields acceptable swr. (External meter) Through the cf-360, swr increases on 10m slightly, but jumps up from 1:1.5 to over 4 on 2 meters.

I did a continuity check and the hf side shows center to center continuity, and shield to shield continuity. The 6m-440 side however is not showing continuity through the center pins. I'm not sure if this is expected behavior through the duplexer or if this is telling me the smoke got out.

Any thoughts on what to check next?

Thanks!

73

Dave
Logged
K5LXP
Member

Posts: 5342


WWW

Ignore
« Reply #1 on: June 08, 2011, 06:02:04 AM »

I did a continuity check and the hf side shows center to center continuity, and shield to shield continuity. The 6m-440 side however is not showing continuity through the center pins. I'm not sure if this is expected behavior through the duplexer or if this is telling me the smoke got out.

Answer:  Yes, this is correct.  It just so happened the CF-360 is one of the ones I tested recently:

<http://www.eham.net/ehamforum/smf/index.php/topic,75573.0.html>

Quote
Any thoughts on what to check next?

How does it behaves into a 50 ohm load?


Mark K5LXP
Albuquerque, NM
Logged
KJ4OBR
Member

Posts: 112




Ignore
« Reply #2 on: June 08, 2011, 06:24:02 AM »

I did a continuity check and the hf side shows center to center continuity, and shield to shield continuity. The 6m-440 side however is not showing continuity through the center pins. I'm not sure if this is expected behavior through the duplexer or if this is telling me the smoke got out.

Answer:  Yes, this is correct.  It just so happened the CF-360 is one of the ones I tested recently:

<http://www.eham.net/ehamforum/smf/index.php/topic,75573.0.html>

Quote
Any thoughts on what to check next?

How does it behaves into a 50 ohm load?


Mark K5LXP
Albuquerque, NM




That is my next step I ran out of time last night (with 2 small kids, radio time can be scarce) ;-)

Logged
Pages: [1]   Go Up
  Print  
 
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!