Thursday, September 6, 2012

SoundBytes 9-6-12

In this edition, we explore one more of our new C-19 release, discuss upcoming appearances, and for our Tech Tip, delve more into speed settings.

In other big news…
SoundTraxx was selected as one of 50 Colorado Companies to Watch by the Office of Economic Development and International Trade! This is a big honor that will come with TV and media coverage. A special “Thank You” to all the discerning modelers who have helped push us to what we are today.

Blackstone Models C-19
Included in the newest C-19 lineup is D&RGW No. 342. This interesting loco traveled throughout the narrow gauge in Colorado in her lifetime. Number 342 was operated out of Durango in the early to mid 20s and out of Salida, Colorado in late 20s and early 30s, primarily as a switcher.

She also was operated from Ridgway to Ouray in the mid 30s until her untimely demise in 1938. Blackstone Models has modeled this little engine adorned in the Royal Gorge herald paint scheme. Sporting a road pilot, flat smokebox door with box number plate, rounded steam and sand domes, a box headlight and a prototypical straight side tender, this sound-equipped, ready-to-run model can be at home on any narrow gauge layout. Reservations are due by September 28th, so hurry down to your favorite dealer and get yours ordered today!

B310209-S D&RGW C-19 No. 342
B310209W-S D&RGW C-19 No. 342 Weathered

Upcoming Shows.

Next up is the National Narrow Gauge Convention in Seattle, Washington from September 12th through the 15th. We will be attending and giving clinics and demonstrations throughout the week. If you are in the area, be sure to come by and see us and say “Hi!”

Tech Tip: Speed Tables
Setting up speed tables can be quite an undertaking, but by following a few easy steps, it can be much less of a hassle. Following up from our last post, we’ll use the speed table to limit top speed, and then to speed match locos. First, let’s look at the affected CVs. CVs 67 through 94 correspond to each of the 28 steps in a 28-step table (CV 67 is step 1, CV 68 is step 2… CV 94 is step 28). As we learned in the last post, the decoder calculates the in-between steps when in 128-step mode. CV 66 and 95 are trim CVs that adjust the entire speed table (default of custom) up or down to compensate for mechanical differences in forward or backward respectively.
When setting top speed, first you have to decide how fast is too fast. Many times, you can use a scale speedometer, or a foot per second rule to determine the speed of a loco. Once you determine top speed, to get an even, linear speed table, we’ll do a bit of math -- don’t worry it’s not difficult! Let’s say you desire the top speed of your model to be the same as it when set to ¾ throttle. Each step CV can be set from 0 (0% throttle) to 255 (100% throttle). So for ¾ speed as top speed, CV 94 should be set to 192. But how can we determine the values of CVs 67-93? Simple math. Divide 192 (Value in CV 94 as determined by top speed) by 28 to determine the number by which to increase and decrease each step. This yields 6.8, which rounded off is 7. Set CV 93 to 185, CV 92 to 178, and so on until CV 67 is set to 6. Run the loco, and the top speed, step 128, will produce a ¾ top speed.

Almost every loco out there seems as though it runs better in forward than when in reverse, or vice versa. The Tsunami decoder uses CV 66 and 95 to help overcome these differences for a more consistent, predictable speed, no matter the direction, for better consists. If the loco runs slower in reverse than forward due to better broken-in gears in forward, then use CV 66 to slow the motor down when in forward. CVs 66 and 95 multiply the speed table by X/128, where X is the value of the CV. The default value for CVs 66 and 95 is 128, so this will have a multiplier of 128/128 or 1, or no change.
Translated, values of 129 through 255 give the speed table a 1+ multiplier, and therefore cause the motor to turn proportionally faster throughout the speed range. Values of 1 through 127 give the speed table a fractional multiplier, which causes the motor to turn proportionally slower. This is applied to the entire speed table, the default linear table or a fully custom speed table. Values farther from 128 will give more drastic changes. Just remember, to set CV 29 for alternate speed tables and CV 25 to 16 for user adjustable speed tables. Using CVs 66 and 95 can also be used for quickly speed matching locos.
Using these methods, you can have the easy, full custom speed table you desire.