[Hallicrafters] off-subject motor speed control

[Edward B Richards]

Good Morning Gang. I apologize for posting an off-subject post, but
obviously I am going to do it anyway. There is such a mass of talent on
these reflectors I don't know where else to go to get technical advise.
Among my problems are bad knees , hips, and back. My doctor won't allow
knee surgery because the anaesthetic would be risky for me with my heart
trouble (CHF). I use an electric scooter to get around although I can
walk short distances. Twice now, the controller for the scooter has
failed. It is an older model and no longer made. They are hard to find
and expensive when you do. The speed is controlled by twisting a handle
grip, like a motorcycle. This goes to a controller that allows the
current to flow to the motor. When the controller goes out the motor will
not run. It is a 24 volt motor with 2 each 12 volt batteries in series. I
don't know the motor current but the whole scooter is protected by a 15
amp fuse that includes a couple of lights. I would say 15 amps to be
safe. I am looking for someone who is able and willing to help me design
a simple controller that I can build. I am thinking of a pass transistor
controlled by a potentiometer. Maybe a DC amplifier in between. I don't
know enough to do it by myself. Thank you.

73,   Ed Richards   K6UUZ