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@Manitou posted:

I just cannot slow down the train, or halt it in any way.  I can only put the train on the track with the power turned completely off. Once I turn the power switch on the train springs to life. If I rotate the red knob on the CAB-1 clockwise, the train will speed up to the point that it de-rails going around a bend. If I rotate it counter clockwise, it does nothing.

The Command Base must be powered up before the track so the TMCC equipment knows whether to come up in conventional or command.  Let's eliminate the PM-1 as your roadblock:

Hotwire that PH-1 directly to the track w/o the PM-1 using wire stripped & folded back on itself to plug in to the two occupied sockets on the PH-1 cord - polarity doesn't matter for this test but the PM-1 passes the center socket to "A" and the outside one to "U" if you want to keep it straight for logic continuity. Connect Command Base "U" to an outside rail.

Power up the Command Base.  Check with your remote that the base is receiving signals from the remote - light flashes on base.

Put the train on the track and, keeping your finger on the switch, power up the PH-1. If it takes off in conventional, it is not receiving a TMCC signal from the base... shut down PH-1 immediately to avoid crashing, and go back to your power supply and maybe switch the ground coupling to the other AC output and test again.

As GRJ stated, "repair or replace?".  I would vote for replace.  But one last test:

The TMCC Command Base broadcasts its RF signal A) into the outside rails of the track via the track wire connection, and B) into the house wiring ground (green wire).  The TMCC receiver in the locomotive senses the RF voltage from the track and the signal emanating from the house wiring.

At this point, the replacement wall wart is powering the Command Base which is responding to the CAB-1 remote (red LED flickers).  The ALCO PA-1 is not responding the the TMCC signal.  Potential causes: the Command Base may not be transmitting the RF signal; the antenna (house ground connection) is not connected; or the ALCO's TMCC receiver (or antenna inside the engine) may be at fault.

Two TMCC receivers are on hand - the 6-24130 PowerMaster, and the 6-18952 ALCO PA-1 Diesel. We know the ALCO is not responding correctly.

The first test I would run would be to determine if the TMCC Base is transmitting the RF signal to the Powermaster.  Does the Powermaster have a flickering green LED that indicates a weak RF signal?  If the LED is solid green, set up the PowerMaster to run in conventional mode and determine if it can be commanded using the CAB-1 to control track voltage.  If you can verify that the TMCC PowerMaster is receiving the RF signal and responding to TMCC commands, then the ALCO's TMCC receiver/antenna is probably failed.

If the TMCC PowerMaster has a flickering green light and/or is not responding to TMCC commands from the CAB-1, then look at the RF signal broadcast from the Command Base.  The signal via the wall wart power connection may not be getting to the house wiring.  This can be overcome by connecting a wire to  your black/green wires on the wart and running that wire alongside the track and PowerMaster.  This provides an "known good" alternative antenna for the TMCC signal (*).  If both the PowerMaster (in conventional mode) and ALCO still don't respond, then the Command Base's RF output has likely failed.  Replace the Command Base.

If the ALCO's TMCC reception is bad, then I would open up the ALCO and look for a bad antenna connection.  The antenna is likely a copper strip hot glued to the underside of the loco's shell with a wire to the electronics.  If these have come apart, the loco can't receive TMCC commands.

(*) Another source for the Command Base's RF output is pin 5 of the DB-9 serial connection.

A Powermaster receives its commands directly from the Cab1. It does not get its signal from the command base. The powermaster and Cab1 were released before the command base.

Some of the variables need to be eliminated to get a better sense of what’s happening although from what we are gathering it is looking like the TMCC base.

Last edited by MartyE

Both the Base-1 and the Powermaster have strong green lights that do not flicker. When any buttons are pressed or the red throttle knob on the CAB-1 are manipulated the red light will flicker on both the Base-1 and the Powermaster giving the indication that they are receiving signal.

I will check to make sure that the Alco's antenna is intact, but (I realize my knowledge is very limited) I am really wondering about the grounding connection in my home made wall wart. It is the only "non-standard"/"non Lionel" component

Manitou, try the alternate antenna wire before disassembling the loco.  If you have a DB-9 male connector handy, pin 5 is the recommended antenna output for improving the TMCC signal.   (Pin 5 and the sleeve connector of the Command Base should be electrically connected.)

Marty, I was describing the current PowerMaster operation which gets the TMCC signal from whatever base is used (Legacy, 1L, or original TMCC Command Base). Do you know what year Lionel switched the design to TMCC RF?

Manitou, if you have an early PowerMaster that gets signal directly from the 27.255 MHz CAB-1 signal, then disconnect the TMCC command base and run the ALCO in conventional mode.

I finally got around to setting everthing back up for my O gauge. I took a single strand wire and inserted it into the serial connection terminal pin #5 and ran that directly to the house ground pin where the home made wall wart plugged into the power strip. I powered up the power strip which powered the Base-1 and PM-1(but left the 135w Power house transformer turned off ). I placed the Alco-1 locomotive on the tracks and let it communicate. After about 30 seconds I turned on the Powehouse and the train runs as it is supposed to. I can control the speed and the bell and horn sound when their respective buttons are depressed.

Thank you for all of your help.

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