Thank you Laurent, I have been to this site but had no luck locating a repair manual diagram. I am trying to find information without a cost. It is even a difficult repair manual to find to download at a cost.
I beg your pardon. I just now found out that there are indeed tungsten-cables.
I found such in the New F1 where it seemingly actuates the viewfinder speed scale. I still haven't found such in the AE-1P. Actually I can't think of a funtion there. But I'll find out...
With actuating I meant a mechanical action, as in moving a display in and out. On the AE-1 there is the pointer of the meter, for the rest there is no further mechanical action.
The tungsten wire connects the ISO resistor to the shutter speed dial which is also a variable resistor.
The setting of the ISO dial changes the position of a cam that engages the shutter speed dial start point.