Engine Revs w/motion but drops to idle sounds while moving...More ?, Pix Added

Years ago I bought an ICG gp-38 from weaver that had the same problem...sent it back and got it corrected.  I also had a tmcc lionel santa fe b unit with the same problem...I think I had this too corrected...but have not run this for years so I don't remember.  I think they both had the same kind of period sound units in them.

Reset may cure this...

If a configuration reset doesn't fix this, it's probably the RS audio board.  Try a different diesel audio RS4 board in it and see if you get the same symptoms.

Try  re-programming, if the problem still is the same you have a bad VCO circuit.

Bill

I plan to try a reprogram but I need the number that it takes to complete it.  The engine did not come back with any instructions so I do not know the number.  Any ideas...

Here's a copy of the generic TMCC reset instructions.  I'm suspecting you'll be using Alt1-5 or Alt1-8, depending on the presence of smoke capability.

Thank you...  that's exactly what I wanted.  Will give it a shot when I get hold of the engine.  I believe the installer will repair it if this does not resolve the issue.

Hope it's just a simple reset.

The Railsounds board requires a CAM signal to maintain the RPM level.  Probably the TMCC conversion process left the CAM out.  You can try to enter manual RPM mode by pressing the "6" key (RPM up),  The "3" key is the RPM down.  It may not hold the elevated RPM level however, only the ElectricRR upgrades had the ability to hold the manual RPM level without a CAM.  (We developed custom code for this feature.)

If the RPM won't hold in manual mode or the person does not want to use manual mode, you will need to add the CAM.  A reed switch can do the task.  Most upgrade boards have a CAM input.

Jon, don't thought some of the boards had a VCO that generated that signal.  The TAS EOB board I'm currently working on will vary the RPM with no cam input and any RS Audio board installed.  It also holds the higher speed as long as the motor is running at the same rate. 

The steam version has the external chuff input. 

John

If it was upgraded to tmcc using lionel parts and not ERR or TAS then it would require a switch, cam or the vco connected to the motors. If using ERR they might have not connected the VCO to the motors, if that is the case then the rev's would return to idle.

Bill

John, true, EOB could generate a CAM signal.  Still, I believe that the missing CAM is the core issue for the failure. 

Since the EOB VCO was directly wired into the motherboard, I surmised this was not an EOB install because that wiring would be unlikely to fail.  Anyways, EOB or not, it needs a CAM to operate properly, or it will ramp down.  The RPM ramp down after motion is a dead giveaway it is missing the CAM signal.

Ok...  if this is the case, and by what you're saying it sounds very probable, can this be repaired by the original folks that did the install?  It was upgraded by Gary w/Weaver.  Is it possible that it was there and it has failed or disconnected?  I am not as familiar with these board sets as I am with MTH, so I'm not entirely sure what a "CAM", in this instance, is.

I guess nowadays that Weaver is using the ERR stuff, so the motor connection certainly seems to be the top suspect. 

Thanks Guys, haven't had a chance to check out the loco yet.  Am hoping it will be a simple fix.  Fingers crossed

I think I'd probably trust Jon to know the issue, it could be as simple as a missing wire.

I finally got together with my buddy and tried the reset, no joy   So...  here are some pix of the innards of this engine.  If I understand the manual that Boxcar Bill linked to, this engine does not have the "VCO" connected.  My question is...  should it be or should these boards have the "CAM" that Jon wrote about?

Please forgive the timidity, but, is the VCO connection what I need to do, for sure?  If this were mine I'd just "do it!"  Just trying to be sure.  Would any pix from another angle help?

Thanks again!!!  Really appreciate your help!!

There's no downside to connecting the VCO to the motors, and it should solve the issue of the motor revs.

The curious thing is the RailSounds Commander in the pictures doesn't exactly match any of the ones I have installed or the manuals, including the one that Bill linked.  I wonder if that's just an older version of the RailSounds Commander?

Here's the page that describes what I believe your configuration should be.  As you can see, there is no five pin connector, and the other connectors are not in the same positions.

Click on the picture to expand it.

Cheryl

   The first pic in looks like a lionel sound mother board, 691PMB2A02.  In the first pic were is the red, black and gray wires connected , could you take a pic were the wires go to, I believe they are connected to a hall effect switch. If it they do go to the hall effect switch, the switch, wiring or the motherboard is bad. Try hooking the motherboard vco to the motors.

Bill

Bill, thanks again for your response and patience.  I'm at the shop now, will shoot the pix and post when I get home tonight. 

Thanks for the clarification Bill, I was wondering what board that was.  It does look like the one she has.

Bill, do you have the pinouts for this board?

John

    I don't have the pin outs for that board, Sorry.

Bill

Cheryl, The VCO is a CAM pulse generator.  Try hooking up the VCO as suggested.  If you need a cable, email me with your address and I will ship one to you.

John, the pinout on the board you picture is the same as the ElectricRR upgrade board, with the following changes: The additional 3 pins by the speaker connectiosn are for the POT, as the POT is not installed.  The small 3 pin connection (lower left) is an additional input to the RS board for an "angle sensor"; used on the Vision rolling stock product; not active in the code on any other RS audio boards.

Thanks Jon, there is no 5 pin connector on the RS Commander, so that must be different as well?

"Cheryl, The VCO is a CAM pulse generator.  Try hooking up the VCO as suggested.  If you need a cable, email me with your address and I will ship one to you."

Jon,

Thank you for the affirmation and the offer for the connector.  I do have some from various other engine projects that should work.  It appears to be the standard two pin connector found in most of the O Gauge train products.  Will post the results of my efforts later tonight.

Wow, it worked.  Yippeeeeee!!!  Thanks guys for all your input.  I will have a soon to be very happy buddy.