Marathon (Controller type) Pot-Box throttle has got me stumped.

[JohnnieB]

Those of you that have read my posts know that I'm at least halfway decent at reading schematics and figuring out how things work.
Well, the schematic of a pot-box Marathon controller cart has got me chasing my tail about how the throttle works.

Nobody I know has one, so I can't eyeball the wiring and figure it out, so I thought I would ask here.

Attached are two schematics, one shows the current path of Throttle circuit with the microswitch on the F/R assembly open and the other with it closed.

I believe the microswitch contacts are open unless the F/R switch is in Reverse.

That puts a fixed resistor in series with a variable resistor (Potentiometer) during Forward operation.
I saw somewhere that the fixed resistor is about 470 Ohms, so let's round it up to 500 Ohms for simplicity.
That would make the throttle range from 500 to 5500 Ohms.

With the microswitch closed, the variable resistor is effectively bypassed, so controller only sees the fixed resistor at the throttle input.
That means the cart only travels at one speed in reverse, rather the having a reduced, but variable speed reverse.

I suspect the schematic is drawn incorrectly and the cart actually has a variable, but reduced, speed reverse.

Would someone that has a controller Marathon with a pot box throttle, or knows for sure if it has a variable speed reverse, please enlighten me.

FWIW: I was so depressed about not being able to figure this out on my own, I sat on the back porch and watched the grass grow while I smoked a Macanudo Crystal.