Postwar whistle tender, only whistles when engine on track.

Well, in troubleshooting, the number one system check is the fuse first, not an issue here, and then the voltage.  So, do you have the track voltage turned up enough?

Perfectly normal. \

Why? A simple answer- some amount of resistive load- be it the smoke unit or as simple as the headlight bulb, or even the load of an E-unit.

That load helps the powermaster better manipulate the AC waveform making the DC offset more prominent in the track power- and building a stronger field in the shaded pole relay- AKA your whistle/horn relay.

@Vernon Barry posted:

That load helps the powermaster better manipulate the AC waveform making the DC offset more prominent in the track power- and building a stronger field in the shaded pole relay- AKA your whistle/horn relay.

Thanks, an explanation is always helpful.   

I have Voltmeters connected to track.   I did further tests using the same voltage reading.  Removed engine from the track and added a lighted car.  No whistle, LED light in car.  Added a car with an incandescent light and whistle worked.   

@VHubbard posted:

Thanks, an explanation is always helpful.   

I have Voltmeters connected to track.   I did further tests using the same voltage reading.  Removed engine from the track and added a lighted car.  No whistle, LED light in car.  Added a car with an incandescent light and whistle worked.   

Same reasons for adding a tiny capacitor to an LED circuit for a headlight on an R2LC TRIAC controlled output.

An LED load is not enough load for the TRIAC to trigger and conduct- but you add a resistive or capacitive load- now the TRIAC conducts as intended.

The Powermaster and electronic controlled transformers like a CW80 using TRIACs to shape and control the waveform to include bell and whistle function DC offset distortions to the AC wave form need that load- ideally a resistive load- can be as simple as a light bulb in a lighted lockon.

FWIW, way back, the exact moment- 10/4/19, when I got schooled by @gunrunnerjohn on using a capacitor to load the typical TRIAC light controlled circuit.

https://ogrforum.com/topic/103...0#103777491014667070

I get a more positive response using the bell button instead of whistle.