Hi all,

We have the Sinclair document in our "Files" section with a good explanation and
in it are details for a 600KHz split 2m ring.

BUT, no scans of the bare ring showing (hopefully) the notch where the two signals,
one 180 deg. out of phase cancels the other. 

Jim WB5WPA, is he still around?

I found his archived article (his webpage has gone) and I'm "having a go".
My constructed ring of 1/4" heliax did nothing useful:
See the last pixture:
http://www.unixservice.com.au/hamradio/repeaters/duplexers/hybridRing/dup6mHR.html

Does anybody here have any experience? 

================
 found this archived web page by Jim and used it as a base for making one, I've added comments and pixtures.
http://www.unixservice.com.au/hamradio/repeaters/duplexers/hybridRing/dup6mHR.html

I've read the Sinclair article and it makes it look easy to achieve the two chains, Rx and Tx.

So, not having any RG-214 on hand, I tried with 1/4" heliax wound in a three turn loop, this for 2m.
My cavity is an RFS six inch.

My problem
==========  Achieving Notch then pass.

The Sinclair article "stubs" are approximately 1/4 wave lines where they can adjust to
"look" inductive or capacitive.

Jim's article mentions a small box and using a fixed L and trimmer C.

Jim's article also mentions "striplines".. Where and how do they help?

Filing notches in the heliax I used was very fiddly, particularly soldering to the inner and, when
soldering the outer, the foam dielectric melts and swells.
I can see, short striplines could make cable termination and T junctions easier.

I've been prompted to revisit the Hybrid Ring as here in Australia, duplexers for 2m and 6m
are just not available surplus. Period. But, combiners and bare cavities, some 3/4 wave for 70cm
are out there.

So, that's why I have to start with bare cavities.

Has anybody here had experience in building one?