If the Fozgometer does not depend upon crosstalk in both directions in order to help the user set azimuth, then it is poorly conceived. However, I have to suspect that it does give an end point for azimuth angle that depends upon crosstalk, but the actual readout of crosstalk in terms of its magnitude is not made available to the user. But I have never seen a Foz in the flesh, much less used one. The Feickert device is not the only other option, in any case, good as it may be. I've got a Signet Cartridge Analyzer that must be 35-40 years old. Used in conjunction with its dedicated test LP, the Signet tells you crosstalk, in both directions, in db units.
I have become somewhat of a nihilist when it comes to setting azimuth by electrical measurement. If the transducer mechanism in the cartridge body is properly aligned with the cantilever and stylus, then the good old mirror or other eyeball judgement that the stylus is square to the groove is all you need or want. If the transducer is out of alignment with the cantilever/stylus, then you are going to end up with your stylus tip at some angle with respect to sitting squarely in the groove. That produces the negative effects I mentioned to fuzztone; the stylus will wear unevenly, the side stresses on the suspension can wear on it too. And ultimately, the LP will be damaged. So, I have come to prefer setting azimuth physically, by seeing that the stylus sits squarely in the groove. For high quality cartridges, manufacturing tolerances ought to assure that the transducer is lined up with the business end, although we all know that occasionally is not the case. I would maybe set azimuth on a new cartridge using electrical measurement of crosstalk. If I then find that the azimuth angle is extreme when I view the cartridge from the front, I would return the cartridge to the dealer or manufacturer and ask for another sample. Then too, there is the secondary question of whether one aims for EQUAL crosstalk, L to R and R to L channel, or lowest crosstalk in those two directions, irrespective of whether the absolute values are equal or not. In every case where I have done electrical measurements, those two options are mutually exclusive.
