EXPERIMENT 2 (performed 9 january 1999).

Theory (figure below).

The frequency has been decreased to 1 Ghz to avoid the attenuation problem and the direct input-output coupling due to a bad shielding of one low cost cable (RG58).

And the magic tee phase detector replaced by a double balanced mixer (SMD-C2 from Synergy Microwaves), thus permitting a continuous phase variation detection .

All the electronics works fine and is very sensitive. The slightest distorsion of a cable or the azimutal mount on which the cable parts are glued is detected with a noise free large dc output signal .

Instead of using lengths of 15 m, lengths of 0.84 m have been used.

The measurement arm is composed of 16 pieces of cable type 1 and 16 pieces of cable type 2 arranged in the sequence 1,2,1,2,1, 2,1....etc...

The compensation arm is composed of the same pieces, but arranged differently in the sequence: 1,1,2,2,1,1,2,2,....etc...

Experimental setup.

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