[RodB]

Hi. It's important to remember that the potentiometer may measure 11K, but a measurement should be taken across one of the end terminals to the center terminal while moving the control through it's entire swipe. Look for a smooth change in resistance. Quite often the wiper will have dirt and have intermittent contact. This can usually be corrected with an electronic cleaner spray. Here's a link to the battery eliminator I have used in my meters.
https://forums.qrz.com/index.php?threads...it.650848/
I have also used the LM317 adjustable regular circuit but this one works very well and is simpler.