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Note the difference in amplitude, which is not very important, this is a Double-Balanced QSD, and everything cancels itself
out, all sins disappear, and even if they didn't, we still have an amplitude balance adjustment later, which is R27, the I-Q
balance trimmer potentiometer.
Note the 180-degree phase difference between the two channels, which IS important. Critical in fact, to the design of the
mixer, which is a Double-Balanced QSD. If the two input signals to the QSD do not have a 180-degree phase difference,
then it is highly likely that you have mis-wired T1. Remember that the manual prescribes a method for winding T1 which is
designed to ensure that all the windings are in the correct "sense" and the ends of the windings go in the correct PCB
holes, to ensure correct phasing of the T1 secondaries. So if you don't see 180-degree phase difference, go back and
check T1 again.
