Reply to "Amp Gauge waving like a beauty queen in a parade"

I can imagine the operation of the altenator and regulator be sort like

from idle up to X rpms, the regulator will be the full field setting given the output of the altenator is very speed dependant. at idle, the charging voltage will be low and as rpms increase so will the charging voltage up to the desired value.

when greater than X rpms, the regulator has to start switching between full and half field to keep the desired charging voltage. as speed increases the switching will stay longer at the half field state up to the speed Y in which half field alone is sufficent.

I don't think there will be much of a speed range above Y where the regulator stays purely at half field, but will start switching from half to no field. My anysis of the circuit does cause me to have questions when this occurs as it appears the relay to switch from self feed back to battery feed may occur when zero field switching. so maybe there is some built in dead band to have a high rpm zone with just half field and zero field only needed at extreme high RPM

IF you care to take some data
----RPM------|--VDC--|--VAC--|--Freq--|--ampmeter wave--|
(every 200)..............................................yes/no

Thats just my two cents

these types of questions makes me wish I had started the rebuild on mine when I had access to vast diagnostic instrumentaion