What becomes all the energy sent by my TX on 160m ? What become de standing
waves and reactive load ? Is it possible than all 100W are lost in the coax
or the feeder without be emitted ?

As I understand it, this is a very common problem if you try to feed a
doublet antenna which is quite a lot shorter than 1/2 wavelength. The
antenna presents a highly capacitive load to your tuner. If your
tuner does manage to match it, you'll end up with extremely high SWR
on the feedline, and very high currents flowing in the tuner's
inductive component(s). Most of your transmitter's power is being
dissipated as heat, due to the resistive losses in the feedline and in
the tuner inductor(s).

Trying to drive a too-short doublet has been the cause of more than
one thoroughly-destroyed antenna tuner - the heat dissipation can
crack toroid cores, melt the plastic forms in roller inductors, etc.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
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