Gadget -- The Custom Electra tuner/preamps in fact use a very large pulley on the tuning cap to achieve what you're talking about. The RF assemblies in the stand alone tuners usually use a gear reduction mechanism inside the RF box. I've determined however that I really jumped the gun with my comment, and could really take it out of the thread. I've compared the tuning of this unit now with that of an FM-100B, 200B, and my R-200, and completely withdraw the original comment. I should have checked it further before making it.
Vendo -- The >30000 serial number units are by far the most desirable units to have, as in those units, Fisher got the signal path correct regarding the Tape Monitor switch, Tape Recording jack, and the Stereo/Mono Mode switch. In earlier units like mine, the signal goes to the Tape Monitor and Tape Recording jack first, and then to the Mode switch -- which (for example) screws things up if you want to have the AM tuner signal appear at both Recording output jacks. Later units (>30000) have the signal go to the Mode switch first, which corrects the problem. I've corrected the issue in my unit, but with how dense the wiring is, it ain't an easy job! Not to do neatly anyway. There were other changes made too, but this was probably the biggest one.......
Dave
Vendo -- The >30000 serial number units are by far the most desirable units to have, as in those units, Fisher got the signal path correct regarding the Tape Monitor switch, Tape Recording jack, and the Stereo/Mono Mode switch. In earlier units like mine, the signal goes to the Tape Monitor and Tape Recording jack first, and then to the Mode switch -- which (for example) screws things up if you want to have the AM tuner signal appear at both Recording output jacks. Later units (>30000) have the signal go to the Mode switch first, which corrects the problem. I've corrected the issue in my unit, but with how dense the wiring is, it ain't an easy job! Not to do neatly anyway. There were other changes made too, but this was probably the biggest one.......
Dave