This was what I was looking for. Dropped CV5 to 127 and now I have a lot more room on the throttle. Thanks.
Most likely, you really only need to adjust ONE - CV5, the top speed. If, for example, the loco currently runs twice as fast as you want it to at full throttle, cut CV5 in half, to 127 (the default of 0 ALSO means 255). That will make the top speed half of what it was when you run at the highest speed step. All steps from stop to full throttle will be linear - each will raise the speed by approximately the same amount per step until you get to full throttle. And you will still have the full number of speed steps, even though you cut the top speed in half - it will still take 28 or 128 steps to get from stop to full speed, it;s just that each step will be that much smaller a change.
As you may not in several MR loco reviews, if you use a system that defaults to 28 speed steps, try the 128 step mode - every time they include this information in a review, the loco in question had a much slower start speed when using 128 steps.
The only reason to adjust CV6 is if you don't want this linear speed change. Default here is also 0, which means "in the middle of" whatever the difference between CV5 and CV2 is. If CV2 is 0, and you reduce CV5 to 100, leaving CV6 at 0 means it will act like it's set to 50. In this case, if you set CV6 to less than 50, each step of the throttle from stop to half speed will be a much smaller change in speed than each step of the throttle from half to full. If you set CV6 to something bigger than 50 (but do not exceed 100 - decoders do funny things when you give them conflicting information that way), the each step from stop to half will have a greater effect on speed than each step from half to full. For a switcher, you probably want the former, however if the out of the box top speed is REALLY fast and you have to cut down CV5 a lot to get it to run no faster than 26mph, each step will have such a small effect on speed that you probably won't have to touch CV6.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Nevin,
You may find that whatever TCS decoder you choose, it will be great right out of the box - without needing to adjust any CVs at all. However, the ones Henry mentioned - CV2, CV5 & CV6 - are all you really need to adjust the Vmin, Vmax, and Vmid speeds. And probably only the latter two because CV2 as is will more than likely give you a starting speed <1sMPH.
TCS has become my go-to non-sound decoder installment because their motor-control is top-notch. While I do enjoy sound in doses, motor-control is much more important to me - especially in my switchers. I can live without sound. What I can't bear is a switcher that immediately lurches to 5sMPH on speed step 001.
And I've never had a TCS decoder disappoint me yet. Good choice!
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
CV 2, 5, 6 are start, mid range and top voltage. edit (don't trust free advice on the Internet, its top and midrange.) I would write down the initial values, before I changed anything. If you are happy about it's start, the 5 & 6 are all you need to adjust.
Never hurts to consult the manual before you start http://www.tcsdcc.com/Customer_Content/Literature/Decoders/WOWSound/WOWSound_Literature.html
Henry
COB Potomac & Northern
Shenandoah Valley
I know I have read it some where, but what I would like to do is re-program my engines with TCS decoders so that their top speed is about 25 mph. right now I never go about 20-30% of the thottle. My Tonopah and Tidewater never averaged more than about 15-20 mph in its heyday anyway. What CV's should alter? Thanks.