Conceptually this could be done using 50 ohm coax stub matching.
Starting with the R +j of the four band segments, a design for each band
series segment can be done. Then starting with the shortest series section,
additional series cables can be added to achieve the proper length for the
remaining three band segments. The junctions of the four series coax
sections can be connected with Tee connectors. Then four shunt stubs could be
connected by means of suitable relay on the third leg of the Tee connectors.
I have not done this for the stated application but have used the concept
to switch a 40m beam from cw to phone frequencies with excellent results. In
this case, only two stubs were switched in/out.
When doing the design, there are multiple solutions with stub matching.
Some solutions require a shorted stub, others require an open stub. One can
visit the various solutions and choose one that minimizes the amount of coax
needed.
As usual, I am only the concept guy; you have to do the work. Transmission
line software will make the job easier.
73,
Gerald K5GW
In a message dated 9/14/2014 8:45:25 A.M. Central Daylight Time,
gmarks@neo.rr.com writes:
I have an Inverted-L antenna for 80M & 160M and would like to make or buy
a remote matching system that would work on both ends of both bands that
would accept full power.
I built a system many years ago from a Doug DeMaw, W1FB, article in the
May 1985 issue of QST but it has never worked as well as I wanted for
whatever reason.
If anyone is interested, this article can be found at the ARRL QST
archives http://www.arrl.org/arrl-periodicals-archive-search by entering W1FB
,
1985, May, QST.
Anyone have an idea of a matching system that would do all of the above ?
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