[Antennaware] 60 meter inverted l fcp.... common mode current at antenna feed point...??

[Franco Rosso]

hello all.
this afternoon i connected my mfj259b directely at the base/feed point of
my 60 meter fcp inverted L but i could not take measurements because the
mfj as gone totally unstable.
The instability is completely gone only by reconnecting my home made 1:1
common mode  coke style w2du ferrite bead coke between the analyzer and the
antenna base/feedpoint.....maybe my antenna+fcp setup is reactive at my
target frequency...and due to the reactance my antenna+fcp is  a bit
unbalanced..?
73's franco it9ahh.