HO 2-6-6-2

[bugg]

Just bought the 2-6-6-2 in C&O in HO and the sound was off - one chuff every 4 revolutions. Sent it back to Bachmann and it sounded correct when I got it back. Used it one time and sound reverted to the old problem the next time I fired it up.. Is this something I can correct w/o sending it back again ? Bugg

[bapguy]

Go to Soundtraxx web site. On the bottom right click on manuals. Click on documents for factory installed decoders. Scroll down to Bachmann. Click mon the loco you want and it lists the CV# and what they do as well as factory setting. Chuff rate is CV116 I think and is default value 75. Change this to a different value. Try increasing the value by 5 (IE 80) run the engine. If it gets closer to being in synch, change it higher by 5. If it gets worse, change it by subtracting 5 from the default(IE 70). There might be a formula for figuring this out with out trial and error. Google steam decoder chuff rate. Hope this helps.  Joe

[wjstix]

Yes the Bachmann Spectrum engines don't have a cam to make the chuffs happen. The decoder just works that it makes X no. of chuffs per minute based on how much power you've applied. It's not too hard to increase or decrease the chuff rate, but can take a while to get it 'just right'.

[bmjcook]

Gidday
            If your control system allows it, you can program the CV,s on the main whilst the loco is running. This does not take long at all......Cookie