But wouldn't making your own block diagram help you to understand the
schematic?



Wonder if you've really looked under the hood of the venerable old
IC-22S? Its a real nightmare to trace circuits, let alone, understand
them, even with a schematic. Physically, rather risky at this age, to
pull apart to trace the boards out.... lots of interconnect wiring going
everywhere.... not elegantly laid out like more modern rigs.... and this
unit did not have a VFO, but a matrix of diodes in a very confusing-to-
diagnose PLL circuit.


Ed K7AAT