It is currently Tue Dec 11, 2018 8:21 pm

Click the link below to visit the site sponsor

The Ham Radio Shop




Post new topic Reply to topic  [ 1 post ] 
 Home brew RF combiner / splitter "tuning" qestion 
Advanced Member

Joined: Sun Jan 13, 2013 5:52 pm
Posts: 642
Location: Whitchurch IO82
Feedback: 2 (100%)
Reply with quote
Post Home brew RF combiner / splitter "tuning" qestion
I built this lumped component combiner to run two lowish power, cheap to build Class D amps combined on 137khz. (2200 meters) Whilst it worked the drain waveforms were like those into a very poorly matched antenna load, so I went with a Wilkinson using ferrite beads to make two lengths of Teflon co-ax act as 1/4 waves and a ferrite cored auto transformer. This works well but I want, for the knowledge, to see if I can make the lumped component one work properly. I believe this to be a narrow band, high Q device. Given I have a decent sig gen and scope and access to a very decent SA, can anyone explain in simple terms how I might "tune" it with regard to coil turns or cap values, on the bench, at low power as from the sig gen, to better resonate it please? Thanks. I link to the lumped device and the schematic of the Wilkinson with ferrite, albeit I now use an auto transformer unlike the schematic.


Lumped component I want to tweak to my desired frequency is at:

https://www.amateurradio.com/630m-wilki ... -combiner/

Combiner that works fine :

http://www.w1vd.com/137-500-500WCombiner.pdf


Thanks for any replies.


Thu Jan 11, 2018 9:41 am
Profile Send private message
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 1 post ] 


Who is online

Users browsing this forum: No registered users and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB © phpBB Group.
Designed by Vjacheslav Trushkin for Free Forums/DivisionCore.