Transformer voltage testing higher than marked

[shelbs8346]

I'm new to model trains so forgive me if I'm going about this the wrong way. I have a Bachmann transformer and speed controller that I am using to power a trolley line that I have running through my Christmas village. I ordered a Circuitron AR-2 to auto reverse the trolley (it should be here tomorrow). From what I understand the board needs a min. of 16V but no more than 18V. I tested my transformer output, it's about 21V. Can I wire in a resistor between the transformer and circuit board or is there another way to step down the voltage?

Speed Controller:
Item number: 46605A

Transformer:
Model: AC1601000
Input: AC120V 60Hz 24W
Output: AC16V 1000mA 16VA

[Len]

You should measure the voltage under load. A light bulb of the rated voltage works well for this. Using a high impedance multimeter to measure the output, with nothing connected to the power supply, will almost always give a high reading.

Len

[shelbs8346]

Thanks but now I seem to have another problem. When I turn my speed controller to on my train takes off at full speed. This happens as soon as it clicks on and I have no control over the speed. It intermittently works as it should but I can't make any sense of it. I'm thinking about buying a new one.