What is a CV?

CV stands for Configuration Variable.

CVs are where you can store your chosen settings in a decoder, just as you can store a friend's number in your phone.

• Storing a value of 27 in CV number 1 makes the loco respond to the number 27.
• Storing a value of 8 in CV number 3 makes the loco accelerate more slowly than if you'd store a value of 1 there.

CVs are something you can ignore when you're getting started, except for allocating individual numbers to your locos.

A typical decoder has dozens of CVs where you can customise various settings should you wish. Anything from the loco's maximum speed through to the rate at which a light will flash.

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