Testing Lionel's AC Smoke Regulators

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The Lionel TMCC/Legacy AC Smoke Regulator can be tested with this little test fixture using either a Lionel TMCC Service Station test board or using the RailSounds output connector of an Electric Railroad TMCC Mother board with a R2LC. Any type ERR board will work.

Use a ERR Sound Commander's jumper to connect the Serial and AC to the test fixtures.

The AC Regulator board is connected to the blue terminal strip. Care must be taken to distinguish between the Regulator's brown smoke element output wire and the brown "serial signal" input wire. The AC Regulator the Output wire is the brown wire closest to the Triac on the regulator board. The "serial"  wire is on the outside edge of the regulator board. Some boards have a second black AC common wire. That wire can be ignored.
The board is made from common Radio Shack parts and Lionel 8 and 27 ohm smoke elements.

Board        Radio Shack       276-0148
Terminals   Radio Shack       276-1388
3 pin Header Digi-Key         455-1015-ND 
I used an 8 and a 27 ohm element so the board can also test the  AC Regulators that use higher resistance elements than the usual 8 ohm ones.  Wire the output to the appropriate terminal for the correct element load.
I have used this jig to find an intermittent board that was occasionally only putting out half the voltage.
Cycling the smoke on and off (Aux1 ,9 and 8) eventually proved the board as bad and not a wiring issue.
The voltage out is chopped AC and when measuring with a RMS AC meter will give you a reference but not an true reading of the voltage.  You could look at it with a Scope but trouble shooting usually works fine with just a meter.

Depending on the Regulator version and type the outputs will vary. I have found usually my meter reads 2.5 to 4.5 volts depending on board. The voltage will start at 4.5 and drop to 3 volts on the most recent versions. This is normal. Be sure you use a full 18 volts on the track voltage.