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CBUS DCC Controller

For those using or thinking about using Digital Command Control ( DCC) on their layouts, a MERG kit CANCMD2 is available. At today's meeting of the Virtual Area Group, Martin Perry described in detail how this circuit worked.



All DCC controllers work to an agreed NMRA standard , which sets out how the required  control data is encoded and superimposed on the track power lines. 

The original Rev A board ,CANCMD1 which ran off an ac supply was described and details given on how this could be modified to run off the safer dc power blocks that we are familiar with.

The newer improved CANCMD2  board  which requires a 15 Volt dc supply, has additional leds to indicate when the board is powered up and also to show when track output is available. 

Other improvements are in the design of the power supplies and in the PIC timing now working from an 8 MHz crystal rather than the previous less reliable resonator.

A link will either pass power to the tracks using a CMOS MC4426 chip via DCC booster circuits  where required, or to a programming track using an L6202 H bridge circuit.

A handheld controller CANCAB is also available.

Current prices (MERG members only) in the Kitlocker are 
            CANCMD2  -  £29.47 and 
            CANCAB     -  £39.13

Andy R





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