Zenith G730 AFC questions etc.

[gyrene]

"...The diode that replaced it is just a little guy, looks like a resistor but is usually black with a band on one end only."

And it has to be there,correct? or the machine will not work,right?

The AFC seems to make almost no difference.Lets say that if this radio were still in the development stages at Zenith and I came in with this AFC idea and activated it to show it off to all the other design engineers...it would not impress to much.
Can it be "weak"? or does it work or not work?