K-Line Questions

Can you provide pictures of what you're talking about and where it came from?

Sounds like it could be a volume knob. Does it have a ridge which would accept a screwdriver to turn volume up and down?

Yes, it has a slot to accept a screwdriver.  I was attempting to adjust the volume when it popped off.

Sure sounds like the volume control, and if the top came off, it's broken.  However, it's a cheap part, and you can also jumper the wiring to bypass it and just set it to full volume.

Thanks Gunrunnerjohn and to all the forum members for your valuable insight.  I jumped the wiring and it is at full volume which is what I was trying to accomplish to begin with.  I saw a K-Line PRR K4 with smoke deflectors (K3380-3876CC).  Never saw a model like that before.  I was outbid at the last minute (I believe this is called sniping).  The winning bid was $547.77.  Sure would have liked to have that one.