Having borrowed an oscilloscope to do other tests I also took the opportunity to fine tune the head azimuth of my walkman's. First I started with the DD's: I have to say the head mount is not very stable, the head and pinch roller are mounted on a lever which is pushed forward into the cassette when play is engaged. The head is the farthest from the lever pivot and that combined with the tension of the pull back spring makes the head position not so accurate. The slightest pressure of the screwdriver causes the 10 kHz L and R channel to misalign easily; even after fine tuning the azimuth, the relative phase between L & R is not very stable and shifts after repeated stop & play. On the other hand the relatively cheap WM-22 has a very stable head positioning and the L&R phases respond very nicely to the azimuth adjustment. Very good tape transport, on that specific aspect I would say it is definitely better than the DD's (note that the WM-22 service manual suggest to use a 6.3 kHz tone and I'm using 10 kHz).
