DCC And JMRI Notes

One thing I've discovered about DCC is that CVs 3 and 4 control acceleration and deceleration momentum. This is especially useful for locos without flywheels -- certain older Bachmann locos, like the PC GP40 that still turns up on line, or some of the SD40-2s, have good motors and cardan shaft drives but no flywheels. (A separate problem is that if these locos come "DCC equipped", it's with a very basic decoder that doesn't support most CVs. You will need to replace this for any but very basic DCC options.)

I reset the values for CVs 3 and 4 to 1 on the Bachmann PC GP40 that I worked on a few posts ago, and its response is now very close to any flywheel-equipped loco.

I've only been working with JMRI Decoder Pro for a few months, but I've found that the minimal expense of a USB cable and a DCC interface to my computer has been paying off hugely. Here is some of what I've learned:

• JMRI is a user-friendly interface for DCC. Instead of searching through mnufacturer documentation on the ins and outs of individual decoders and CVs, Decoder Pro can simply take you to function screens, which makes programming decoders quick and easy.
• Beyond that, Decoder Pro is able to discover decoder features that aren't documented in the manufacturer documentation. For instance, the Walthers Mainline SD70ACe with sound appears to have five horn selections via the Decoder Pro panel. In addition, a number of the Soundtraxx limited-feature sound decoders on Bachmann and Walthers locos allow you to activate the automatic sound features, like bell on at low speed and whistle signals for direction, on DCC, when by default they occur only in analog operation.