Switching from fast to slow/stopped locos with DCC

[Anonymous]

What does one do when you take over a slower or stopped loco when running a much faster loco in DCC?

Picture this scenario:

Train 123 is the mainline consist that you are controlling with your throttle. It's running at 60 MPH scale speed. You also have a small switcher in the yard that is stopped. The yard is crowded so there's not much room for high speed antics.

Remember, your throttle is controlling Train 123. Now you want to do some yard work. As soon as you switch to the switcher it will try to assume the speed of Train 123. Since there isn't much room in the yard, the switcher takes off crashing into everything until you can grab the knob and turn down the speed.

How does one handle this situation?

I can see some "solutions":

A) Slow Train 123 down to yard speed or stop it altogether before switching. This is so unprototypical.

B) Switch to the switcher and quickly turn down the speed knob. Now this becomes a game of reflex and reaction timing. This can't be fun at all. :)

C) Spend $65 to get a UT4 throttle (I have a Zephyr) and use that throttle for slow stuff. Now you have two throttles, one for similar high speed trains and the other for similar low speed trains. Now when you switch there's not much speed differential.

Are there better solutions? What do people do in these typical circumstances?

[rrinker]

I think you answered it. Get a UT4, control each train with it's own throttle, or at least use the speed matching ability of the UT4.
OR get one of the fancier DT throttles with encoders - if you had a DT400 and switched from runnign the mainline train to the switcher, the switcher would not move until you turned the speed control, even though you just switched away from controlling a train running at 80% speed. Of course, the DT400 has TWO knobs so you could remain in control of both trains at all times.
People sometimes complain about encoder throttles - here is the primary reason WHY they are good - there is NO chance to accidently leave the speed control at full speed and select a stationary train, only to have it rocket away as soon as it is selected.

--Randy

[Anonymous]

Hold on... do you mean to tell me that when switching to a different engine that the signal continues to be broadcast? I was under the impression that when changing train #s you have to somehow activate the new #. otherwise if switching from 1 to 5 train #s 2,3,&4 would jump as you pasted by on your way to #5, like an old TV tuner.

[Anonymous]

No, it's not like a TV tuner. It's random access and not sequential access so in your example, you just punch in Train #5 w/o disturbing Trains #2 through #4.

However, at least with my Zephyr, if your Train #1 is at 80% and you punch in Train #5, Train #5 will take on the 80% of speed that you just came from (Train #1). Not good if your Train #5 is a switcher in a small yard.

But, it seems like Randy provided another solution. I didn't know that the fancier DT throttles can do that. Now I'll have to take a look. Thanks Randy!

[Anonymous]

What if you were to switch to an unassigned #, then turn down the speed to 0 then select the engine you want?

[Anonymous]

Hmm, never crossed my mine but that would be a solution. I won't mind but I'm sure someone would object to the extra step.

A poor man's DT throttle! [:)]

[NZRMac]

My Lenz has two buttons UP and Down to scroll thru the loco numbers, loco's will do what ever they were doing when you last addressed them.

1 on the main at 80%, scroll thru to a switcher stopped it will stay stopped till you change the speed control.
if the throttle is at zero and you scroll back to the 80% loco it will stay at 80% even tho the speed is at zero, till you change it.

I thought all dcc was like this?

Ken.

[Anonymous]

Apparently if you have an electronic throttle what you described is possible as Randy pointed out with a DT throttle.

However, if your throttle is a mechanical potentiometer based one, then no, it won't work like that. Once you switch loco, the potentiometer is phyiscally set to 80% (or whatever number it was before the switch) and the next loco will take off ( or slow down) to whatever the potentiometer is set at physically.

My Zephyr's throttle is potentiometer based thus my original question.

[rrinker]

Actually, on the Zephyr you don't really need an extra step - just hit Loco, Exit, turn the knob to zero, Loco, enter the switcher's address, Loco.
The trick comes in when reselecting the road engine. But if you get the speed setting close, it won't jerk around - or program some momentum into the decoder so that even if you aren't exactly the same, it won't suddenly slow down or speed up.
Reselecting the road engine would be the same procedure - Loco, Exit to clear the switcher, set the speed control where it should be, Loco, enter road engine number, Loco.

--Randy

[johncolley]

Prodigy Advance has a neat button for recall that allows you to toggle around to different locos. when you toggle to another and enter it, the first one continues at the speed it was going. I am operations oriented and an inbound will enter the A/D track at slow speed and it takes a lot of time to run the length of the yard, allowing me to position yard switchers and/or have another road unit ready for the change. When the stage is set I toggle back to the inbound and slowly bring it to a stop with just enough room to cut off the road engines without fouling the main.

[dave9999]

QUOTE: Originally posted by rrinker

Actually, on the Zephyr you don't really need an extra step - just hit Loco, Exit, turn the knob to zero, Loco, enter the switcher's address, Loco.
The trick comes in when reselecting the road engine. But if you get the speed setting close, it won't jerk around - or program some momentum into the decoder so that even if you aren't exactly the same, it won't suddenly slow down or speed up.
Reselecting the road engine would be the same procedure - Loco, Exit to clear the switcher, set the speed control where it should be, Loco, enter road engine number, Loco.

--Randy

Actually, you don't have to hit the exit key. Once you press "loco", the current loco
address will flash. At this time you can turn the throttle down without changing
the speed of the current loco. Now, while the throttle is at zero and the loco address is still flashing, input the new loco address and press loco again.
The throttle will now be in control of the new address with the throttle at zero.
Pretty simple, I use this method all of the time. Good luck Dave

[BRVRR]

Why not install another power supply, even a train set buzz box, on one of the jump ports? Then you have two, independent throttles.

[Anonymous]

The less expensive DT300 also does what the DT400 does -- it picks up the new engine at whatever speed it's going at, rather than what the throttle is set for. And it also has dual controls. I got a slightly used one for my Zephyr for under $90 on eBay, and it's been the best investment I've made to expand my DCC setup to date.