No Sound Control from pot under Chassis.

[Anonymous]

My conclusion was the slide switch was moved, not in the RS position, one screw was holding it in place. Left it that way, will get a new screw and nut, looks like a 2-56, and the next time I have to remove the shell...will replace the missing screw and nut. By the way where did those parts go ?? Did not find them (yet).

[Anonymous]

So what did you decide was wrong with the pot, just the switch screw missing? If so what did you use to replace the screw that was missing.
Nice to know it this happens to me.
Dave.

[Anonymous]

Thanks, Jim, Roy, Bob and Dave........

This is what I did:
Removed the Diesel Shell, always hate to do this, everything is so tightly packed, those wires crowd both ends and around the motors. However I took resistance readings of the pot......one half about 10K, the other side 4k, seemed to make sense to me. Kept looking and probing and spotted a missing mounting screw and nut holding a single pole switch to the base chassis, this switch is the RS..SS select switch, thats for Rail Sounds or Signal Sounds (according to the K-Line Book). Moved the switch from one position to the other, did this 3 or 4 times. Not seeing any other obvious conditions, except for some wires close to the motor flywheel, I reassembled the Shell, with those 4 tiny screws.
Success this time, it worked, the problem solved.
Also tried the SS switch position, it did work differently than the RS position, all is good again with all buttons of TMCC Cam-1 working.

Additional info: The last time I opened the Diesel was to solder a flexible wire to each roller pick-up, seems that the original wires were very stiff and did not survive my operation going thru reverse loops and 031 curves, this puts a maximum swing on those wires from the pick-up to the circuit board.

Have a good day.....George [:)]

[Anonymous]

I had this hapen with my 1st atlas rs1 and a call to atlas yielded this comment. The resistance wiper in the pot is not mtg properly and will cause this to happen. His suggestion was to take it apart and solder the leads closer in to the pot.
I tried something else 1st and it worked great. I just took a needle nose and turned the mtg nut for the pot tight and presto it works. Try this 1st before you take it apart. It is very unlikely the wires came loose on their own, put if the china pots are made that poor my suggestion might just work for you.
By the way mine was fine at first too, after about 2 months the problem occured but my sound quit due to the pot grounding out all signal.
Dave.

[lionelsoni]

My guess is that the pot terminal at the low-volume end has become disconnected somehow from the circuit.

[Jim Duda]

Can you determine if the wires are still soldered securely to the pot and to the sound board?

[Anonymous]

Moved the pot from end to end three times, then set it about mid-way.
Still the same, comes on full blast.
TMCC works though, pressing '4' button on the Cam-1, I reduce volume....
from Full Blast.....to Loud.......to Medium.....and then off, thats in four steps, tried it many times.

[wrmcclellan]

gwarrin,

Try moving the pot from limit to limit to see if it has a bit of oxidation or dirt that is preventing contact. This movement will "clean" the contact. Otherwise the potentiometer has failed and may have to be replaced. Hopefully you will get good advise from K-Line/Lionel on what to do next.

Good luck,
Roy

[Jim Duda]

Are you saying that your other TMCC stuff sound volume responds to your Cab-1 and/or DCS handheld? If yes, have you "exercised" your control pot by turning it a few times from one limit to the other in case it's a "dirty" pot?

[Anonymous]

Subject: PRR RS-3 Diesel Engine, K-Line, K2480-8445 with TMCC

I have lost use of the Sound Volume Control under the Engine Chassis.
It now comes on at full volume, TMCC still has up and down volume control.
I have always set the Control Pot to mid position, now it has reverted to the as built sound, comes on extremely loud.

What would you suggest I should do next ? [?] [:(]

Sent E-Mails to K-Line and Lionel.