I have a question about DCC decoders. I’ve seen several posts about motor control saying that TCS or LocPilot would be a better choice for improved motor control.
I have one TCS WOW-101 decoder in a Rivarossi oil tender that I can easily put behind any Cab Forward or Y6B in my fleet, all powered by either a single Canon EN22 motor, dual Canon EN22 motors or Faulhaber 2224RS motors (a total of 20 Rivarossi articulated locomotives). Four of the Cab Forwards have been kitbashed into AC-9s. All have 8 to 10 ounces of added weight.
I also have an oil tender with a MRC 1731 Steam decoder that I can swap out with any of my Rivarossi fleet. I must be missing something because I can’t tell the difference in motor control between the decoders. To add a bit more confusion to the pile, I also have an older MRC decoder 1656, several Digitrax decoders and I can’t tell any difference in motor control between any of my decoders.
There is a slight difference between sound, the TCS has the true SP articulated sound.
OK more fuel to the fire, I have eight MRC 1730 Diesel EMD 567 decoders and I don’t see any difference in motor control in those decoders compared to the TCS de
It may depend on how you use them. Since you only mention adjusting BEMF, I assume you aren’t using the momentum settings, or setting speed curves, or speed matching engines. If that’s the case, the engines will run pretty much the same as they did under DC, so there won’t really be much difference to compare.
I’ve never used Momentum, never turned it on the DC power packs that had that feature. As for speed matching I’ve never had a need to do that either. All of my decoders have been plug and play, no matching necessary with one exception. A recent remotor, I used a 8700 RPM Philips 9904 series motor and dropped the motor speed with gears. It’s close enough for steam because I never consist with my steam.
"…So I’m just curious about the statement “better motor control”, what am I missing? "
This statement is in reference to the range in efficacy between brands and models of decoders in the hobby. Initially, when I got into it back in 2005, ESU easily dwarfed the other available decoders with respect to fine motor control, and this applied even to the eagerly awaited Tsunami back in 2006.*
I would say that ESU has largely continued to dominate the market for those who wanted silky-smooth drives, but that changed with the introduction of the WOW several years back. The two brands went toe-to-toe and the difference is essentially negligible…it reduces to fandom.
The statement, to continue, pertained to getting locomotives to start at very low driver wheel revs at speed step ‘one’, and to continue that fine acceleration with each additional speed step. The idea was to overcome the tiny defects in the gear interfaces tha
I find the info very helpful but as I mentioned above, I can’t tell any difference in decoders. They all start the same and when I have a couple of my over weigh E7 tied together (same equipment number) they track very well together, even separated they stay pretty close over my 120’ mainline (loop) including a regular 3½% grade as well as my 3½% helix.
I do run multiple locomotives together for testing purposes, my layout wasn’t designed for multiple trains, I can only run one train at a time. I do not run my steam locomotives in a consist, only my E7s
My bottom line is I can not tell the difference between any of my decoders. To complicate things even more I have several types of motors, Pittman open frame DC70s, Mashima, Canon, Faulhaber, stock Athearn, stock Proto 2K and my latest is a Philips. Every one creeps great and runs smooth regardless which decoder is operating the locomotive.
I only have a total of 17 decoders that I swap around depending what locomotive I want to run. Out of the 17 five are considered permanent, four E7s and one Cab Forward.
The only problem I have ever had was not setting the BEMF and Randy help
There’s a whole group of modelers, or maybe I should say operators? that feel the need to tweek everything, to get things to run the way they think they should, so they use the programing availiable to accomplish this. Which is fine, if that’s what your into, and that group is what the decoder manufacturers cater to, with “new and improved/anvanced motor control”.
I use enough of the capabilities of my DCC system to start and run trains. And that’s as far as I go.
Some thoughts on your observations: Selector is right in that many people were comparing the motor control on the Tsunami with Lok sound. The first generation TSUs had a propensity for what was known as the “jack rabbit” start. While this could be programmed out of the decoder with some tweaking, it was annoying. As a result “better motor control” was an advertising catch phrase. The new TSU2s have fixed this issue.
I would suggest that the type of locos that you are running (big steam and smooth diesels) are making it harder for you to see the differences in motor control as most of those locos will run great with out any tweaking due to the either to the size of the loco and/or the quality of the parts you have use to remotor. When you get down to smaller wheel based steam and diesel critters etc. is where the motor control issues begin to be more obvious.
There is also the “creep factor”. Many operators prize slow speed operation. Some anomalies won’t show up in the meduim speed range but are very apparent in slow speed operation.
I would say in general that you are blessed if everything runs so well that it hard to tell differences in decoders.
I haven’t ever had a problem with any of my locomotives running great on either DC or DCC since Randy helped me with the BEMF settings. I have a couple of rough runners but that has nothing to do with DCC, some mechanical problems can’t be remedied easily especially hard if the manufacturer is no longer around.
I’ve been at this for a lot of years and if I have locomotive with a serious problem that can’t be fixed reasonably then I don’t need it. I’m really into restoring clunker locomotives and when I can’t make it run like new or better then it’s a goner. I’ve only had four out of 70+ that didn’t make it. GS4 pancake motor shells make great kitbash material.
A big difference may be in the speed steps used. I always use 128, which is the Digitrax default. NCE defaults to 28. No idea what MRC does because their ‘simplified’ documentation leaves out things like this - sorry but this has always been my experience with MRC, decoders and their other stuff. There’s a huge difference betwene HAVING the technical details available and REQUIRING you to read said technical details to use the system. A common complaing on Digitrax is that the manuals are too complex. Why, because they provide nearly EVERY bit of information on using and configuring the system? But the first couple of pages are the smae as everyone else’s manuals - hook theses wires to your track, put a loco on the track, press these buttons, and you are running a train. No one says you HAVE to read the nitty gritty details that come later, but Digitrax and NCE provide that information in their manuals. MRC tends to not provide it AT ALL.
Anyway - in 128 step mode the difficiencies of the motor control in many decoders becomes fairly obvious. Even Digitrax - i will not use any Digitrax decoders because of one major fault - computers, including the microcontrollers in decoders, use binary. The calculus used for BEMF control equitions (differentials and derivatives) results in numbers with many decimal places. Not all decimal numbers can be accurately expressed in binary, so there is rounding error. Digitrax decoders seem to lump all that rounding error into two places within the speed range - so between two particular speed steps there is always a ‘jump’ in speed compared to the nice even progression of all the previous speed steps. No matter how carefully you tune the BEMF and other things like momentum, you can never truly get rid of this - it’s always there, and I can handily demonstrate it
For others - the difference is also readily apparent when running at a slow speed. The better decoders will happily chug along non stop at step 1, no stalling.
I normally only swap my TCS equipped tender around to one of my favorite locomotives because of its great SP articulated sound. I only run it with my favorites which all happen to have Faulhaber 2224RS motors. I have 6 locomotives equipped with Faulhaber motors, 4 Rivarossi Cab Forwards and 2 Kitbashed AC-9s from Rivarossi Cab Forwards. The rest of my articulateds have either a single or dual Canon EN22 motors.
After reading your post I swapped the tender with the TCS decoder to a AC-9 with dual Canon EN22 motors and it did exactly what you described. By the second lap it was running normal.
Thanks Randy! I won’t be spending my meager retirement budget on more WOW decoders because of the difference in cost. I wouldn’t have known the difference the way I was operating my DCC equipped locomotives but now I’ve learned to expect different operation from the TCS equipped tender over the rest.
I would like to have one more WOW decoder permanently for one of my AC-9s but at almost 3 x 1 cost it won’t be happening soon. No big deal, my layout wasn’t designed for multiple train operation. I wasn’t thinking DCC back in the 80s when I designed and built it and at 81 it’s
I’m glad to hear that all of your decoders are working satisfactorily. I think that you have proven that in many cases that the difference in operating characteristics is a non issue.
For me, I’m into critters so good slow speed operation is a big issue. For that reason I’m using Loksound Selects simply because they work for me.
When I buy new decoders they will be Loksound Selects too even for the bigger engines, not so much for the slow speed operation, but more for the fact that all my decoders will operate and program the same way. I have a couple of FP7s with QSIs in them and they sound and operate just fine. The problem is that I can never remember which level of shut down they are in or how to start them so getting them running usually requires getting out the manual. Part of the problem is that I don’t get to run them very often because I don’t have my own layout so, given my already forgetful nature, I can’t remember how to run them when I want to. Programming the things is also painfully slow.
By standardizing all of my decoders, when I do get to run my trains at the club, I won’t have to be scouring the manuals trying to figure out how to get them to run.
Thanks for your input Dave. True about standardizing. I experiment with everything I do so I normally end up with some sort of a mix and sometimes I have to bite the bullet.
I forgot to mention that I also have a Soundtraxx TSU-1000 SP Cab Forward sound decoder that works equally as good as the rest of my decoders. It also has great Cab Forward sound.
Randy got me to use the JMRI Decoder Programming software and that took care of my programming issues, that makes programming all of my decoders super simple and I don’t have to depend on my memory.
I have sort of standardized on the MRC 1700 series decoders, they work well and the price is right at just over $40. Not bad for a sound decoder.
As I model the early to mid 1950s I don’t need a large selection of sound. I rarely run any of my GPs or SDs so no decoders for them, when I do run them its in DC mode only. I tried decoders in my MDC Shays but not having a Shay sound decoder to dink around with I haven’t installed speakers in them. My norm with my Shays is DC operation.
I have 5 or 6 1st generation EMD and Alco engines using MDC sound decoders. Just recently installed an MDC sound decoder in an Atlas RS-1, using an MDC decoder with first generation Alco sounds. Worked out quite well; since you already like the EMD version why not try the Alco decoder in your Alcos?
p.s. you could always put a non-sound decoder in your geared steam engine until you find a sound decoder you like for it.
Well yes, if you’ve never used CV 3 and 4 momentum settings then the way the decoders function will probably will seem about the same. Momentum in a decoder isn’t exactly like the momentum switch on a DC power pack. You can set it to be a little or a lot, most folks find at least a small amount helps the engines get up to speed and coast to a stop more smoothly / realisticly.
Speed matching has nothing to do with how the decoder is installed (“hardwire”, “plug-and-play” etc.) but how the engine operates with other engines. Yes, you can re-gear engines to slow it down or speed it up, but you can do the same thing by changing CV 5 (and 6 if available); using CV 2,3 and 4 allows you to have the engines start and stop together smoothly.
Is the decoder your using a 2704? I don’t have any experience with that series decoder. I have a pair of Athearn PA & PB with the original Athearn motors wired for DCC. I could pull the two existing 1731 decoders from another pair and install the 2704s, they have Mashima motors.
I haven’t looked for a MRC Alco 244 sound decoder in a couple of years and didn’t know MRC made them.
I believe it was a 1704, the older version of the 112704 decoder. MRC also makes a decoder with multiple prime mover sounds - two Alco sounds (539 and 244) and four different EMD sounds.
