Topband: Detuning Vertical

[Michael Rauh]

Hello Topband,

I plan to put up a quarter-wave vertical for 160M.  I would like to add an 80M
vertical suspended by a catenary from the larger antenna.  When I model this
situation in EZNEC, driving the 80M vertical results in currents in the 160M
antenna that are about 20dB down.  They are sufficient to distort the pattern
of the smaller antenna.  The 160M antenna is grounded.

What do people commonly do about such currents?  I can imagine using relays to
switch in a resonance breaker part way up the larger antenna.  Is there a
better solution?

Mike Rauh W8GT