since this is becoming a good reference thread for the 148gtl clarifiers, i will add this little tidbit in for those contemplating a 10 turn pot:
first, the shaft on these pots is a 1/4" rounded shaft and the radio knob will have to be drilled out to accommodate it as mentioned earlier in the thread.
the best way i have found to do this and not have the knob look off center or 'wobbly' when turning (AKA to get a truly centered hole that is straight) is to use a drill press.
if you don't have one, and can't come up with the 50 bucks to buy one used, then im sure you have at least one CB friend who has one.
getting these results with a hand drill will be an exercise in hope and karma.
set your drill press up with a 3/4" piece of sacrificial wood centered on the base.
chuck up the drill with a 1/2" drill bit (im guessing here and it could be a little more or a little less).
now with your sacrificial wood clamped securely in place, drill a hole in the wood all the way through.
after this step you don't want to change the orientation of the drill bit or the wood.
now chuck up the drill with a 1/4" drill bit. set the depth of the drill cut so that it will cut through the wood block about 1/4" deep.
now take your radio's knob and place it upside down in the hole you created.
it should go about halfway down and then wedge itself in place.
if it is too loose to be held securely, then use a little electrical tape to shim the knob up to size. it has to stay put in the wood and not turn.
now you can drill out the hole in the back of the knob and it will be centered and straight. if the drill didn't cut deep enough, re-set the max depth another 1/16" and keep stepping up until you drill deep enough to remove all the knurls inside that hole.
i have found when doing this that the knob pushes on the shaft of the 10 turn pot snugly and without the need for any adhesive or shimming.
if you do need to use adhesive, do yourself a favor and use rubber cement so you can remove the knob later.
hope this helps!
LC
