I am sure that this must have been discussed before, but I couldn't find it regardless of the combination of search terms I used with the advanced search.
With DCS, the train or engine speed is displayed on the remote in Scale Miles Per Hour, SMPH. With Legacy, there are more steps available to control the engine speed, but what do the displayed numbers represent: 1/2-SMPH? 1/3-SMPH? Other increment SMPH?
Thx!
Alex
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While the Legacy speed steps are 200, as speed increases, the equivilent smph (proto 2) reduces from 3 speed steps at 10 smph for 1 smph to less than 2 speed steps at higher speeds. Because I run 3 and 4 consists simultaneous with the proto 2 infront of the Legacy or TMCC engine, I am very concerned with this relationship. Most of my trains run at 10 smph which translates to 37 to 39 speed steps depending upon the engine. One further difference is that Subways have a different ratio with my R 27 at 39 speed steps for 20 smph in syncing that consist with the MTH Northern Shore. The switchers such as the Genset are a whole different animal with my Reading triple MU running at 3 smph requires the genset to be at 24 speed steps to sync with the triple. As you can see it is real simple to match speeds and when Albrecht was running my layout with me we had my dual MU MTH electrics running with the Legacy FEF-3 up to 80 smph. I just do not remember what was the Legacy speed steps. Even with my dual SMRs on my O54 6 foot loop I run the proto 2 conversion at 3 smph (actually closer to 10 smph but the small wheels and other operating characteristics of the sound file make this measurement just relative and not a true smph) and the ERR conversion (with cruise control) at 12 speed steps to have the consists match.
Alex,
The following is my understanding of Legacy speed steps, as explained to me by a Legacy operator of my acquaintance. If I'm mistaken, I'm sure someone more knowledgeable than I as regards this subject will correct me.
Not all Legacy engines behave the same as regards speed increments. Different "classes" of Legacy engines go faster or slower than other "classes" of Legacy engines at the same speed step. One "class" of engines, for example, may be diesel switchers and another class may be "steamers", and they would run at different speeds at the same speed step. However, within a "class", all engines should run the same.
Legacy engine are absolute so each speed step is linear. The other cool thing is even though different classes have different speed curves, when in a MU switchers with the slower speed steps will adjust to match the road engine.
Further, speed steps may or may not be linear, i.e., a speed step increment may be a smaller or bigger speed increase depending upon whether it's step 6 or step 60.
Marty,
Thanks for the correction. I've amended my post.
Barry, your comment was correct for the knob control of voltage. Each step of the knob is a equal time increment on the voltage sinewave. Increments near the peak of the sinewave add more RMS power than increments near the tails of the sinewave. This would apply to modern ZW transformers, Powermasters and TPCs. I believe it also applies to TMCC engines, at least those without Cruise.
If I understand correctly -
To find out the SMPH at which a Legacy engine is running and correlate that with the remote display speed number, I need to either (1) time it over a known distance, or (2) pace it with an MTH engine?
Thank you for your replies!
Alex
I use your method 2. I place the Legacy consist on the rails behind an MTH one and spin the velocity wheel on the CAB2 to match and see the speed step read out. This permits me to take conversion engines (ERR and Proto2 kits and find out the necessary speed step to match a given smph readout as I did for my SMR engines. Also, I am not willing to spend the time to find a sound file that will match the smph for a Kline proto2 converted engine such as my Hudson or tank. The hudson runs at a 16 smph indicated to match with my Reading T3 and NW J running at 10 smph. My tank engine runs at 7 smph indicated to match 10 smph for my triplex. Marty I have to disagree with my physically doing this for 8 Legacy engines. The speed steps are not linear over the 200 speed steps (or MTH smph are not). If they were linear, my speed steps of 38 for 10 smph would imply 76 for 20 smph and that is not the case for my 6 road legacy engines.
You can see the speed readout on the bottom right of the CAB2 display(I think it is the engine number). I am upstairs at this point so I can not say which button provides the readout but please note that the setting is not sticky (it does not stay displayed.) The speed steps are displayed any time you move the speed dial under the engine number. After the speed is where you want it and do not change the speed, the text ENG appears over the speed step display. If you move the dial, the new speed step will be displayed. If you want to see the speed without changing the speed step, depress the scroll button twice and the speed step will be displayed.
Tomas, I believe Mike Wolf and his DCS patents are the reason for that.
Most of the posts here explain attemps by Lionel and workarounds by operators to arrive at some common ground when using both systems/engines.
If the legacy does not show speed then what are the numbers on the lower right of the legacy screen under the engine number that start out as 1 and go up the more the red knob is turned?
Legacy displays speed in "Speed Steps" not scale MPH. It was from what we were told a patent issue. Sometime ago someone had a approx SMPH vs Legacy speed step chart.
If you set 2 Legacy engines at the same speed step they should travel closely at the same speed.
Legacy engine are absolute so each speed step is linear. The other cool thing is even though different classes have different speed curves, when in a MU switchers with the slower speed steps will adjust to match the road engine.
Further, speed steps may or may not be linear, i.e., a speed step increment may be a smaller or bigger speed increase depending upon whether it's step 6 or step 60.
>>Legacy engine are absolute so each speed step is linear.
Sorry Marty, not quite correct. Speed steps are closer together relative to track speed at the low end, and at higher speed steps produce a larger speed change.
Non-Linear.
You're the guy that should know! 
That would be my experience as well. As slow speed, the steps are very close. Of course, that's what I want, so I'm happy with that operation!
so the chart is wrong?
maybe santfefan can make a new chart?
Legacy engine are absolute so each speed step is linear. The other cool thing is even though different classes have different speed curves, when in a MU switchers with the slower speed steps will adjust to match the road engine.
Further, speed steps may or may not be linear, i.e., a speed step increment may be a smaller or bigger speed increase depending upon whether it's step 6 or step 60.
>>Legacy engine are absolute so each speed step is linear.
Sorry Marty, not quite correct. Speed steps are closer together relative to track speed at the low end, and at higher speed steps produce a larger speed change.
Non-Linear.
Jon, is it still linear TIME steps like on TMCC? I would expect so.
Marty,
Sorry Marty, not quite correct. Speed steps are closer together relative to track speed at the low end, and at higher speed steps produce a larger speed change.
See, I was correct after all!
I guess you should write that in a book! LOL!
I love learning!
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