I'm running a Digitrax Zephyr DCC system that I finally hooked up to my layout. Everything works fine however I have a question. Say for example I have two locomotives running at the same time (we'll call them #1 and #2). Both are moving at two different speeds and in opposite directions. Let's say I'm currently controlling loco #1. I want to switch to loco #2. When I key in loco #2 (hit loco, 02, loco on my keypad) loco two will automatically take on the throttle settings of loco 1 which means it abruptly changes direction and speed. Is there any way to avoid this? It's a bit frustrating!
Thanks
Todd
You can adjust the 'brake rate' setting in the Zephyr to give it some delay in the speed changes so they aren't so abrupt, but this also adds a momentum effect to every loco you run, in that they won;t respond to the throttle instantly even if the decoder has no momentum programmed in. Or you could program momentum into the locos and they won;t adjust speed instantly.
This is the downside with a potentiometer based throttle - they all do that. An encoder based throttle like the DT400 doesn't do that - you can switch back and forth between running locos and none will change speed until you turn the knob.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
That's quite dissapointing to me. You'd think with technology these days the system would resort back to the original setting when you reselect that loco. Would adding a second throttle like Digitrax UT4 allow me to do this?
Say I'm running loco #1 and I want to change to #2. I press exit, then loco, adjust the throttle to what #2 is running at, loco, 02, loco. #1 keeps going without missing a beat and #2 doesn't speed up or slow down or change direction.
Dr. Frankendiesel aka Scott Running BearSpace Mouse for president!15 year veteran fire fighterCollector of Apple //e'sRunning Bear EnterprisesHistory Channel Club life member.beatus homo qui invenit sapientiam
OntarioTodd That's quite dissapointing to me. You'd think with technology these days the system would resort back to the original setting when you reselect that loco. Would adding a second throttle like Digitrax UT4 allow me to do this?
A UT4, no, because it's also a potentiometer throttle. The UT4 does SLOWLY adjust the speed to match the knobs setting.
Here's why the speed has to adjust. A potentiometer ('pot' for short) has a fixed amount of travel, 300-320 degrees for better ones. There is a physical stop at each end, on side the minimum resistence and the other maximum (more technically correct, a pot usually acts as a voltage divider withthe two end termiansl at extremes and the center contact tapping off at some point in between, placing the output at one or the other terminal's potential or somewhere in between. That's not critical to understand to get this explanation howver, just put it in for the nitpickers ).
At any rate, with the knob turned all the way one way, your loco will be stopped because that's how it's wired into the control circuitry. With it turned allt eh way teh other way, your loco will run at maximum speed. And any speed in between those extremes. Now, say you start loco #1, and adjust the knob to 50% and run at about half speed. Without touching the knob, you select loco #2. If the speed of the loco dod NOT adjust to the knob position, you now have loco #2 with STOP being at 50% of the knob's rotation. You in effect have only half the knob's range to control that loco. Say it did work that way, so now you advance the knob to 75% of it's travel, 50% of the remaining travel, to make loco #2 run at half speed. Now you go back to loco #1. Loco #1 is running at 50% speed, but with the knob at 75% - so to stop loco #1, you turn the knob back to 25%. 75% minus the 50% loco #1 is running = 25%. Getting confused yet? See why they DON'T work like this? If it did, you could end up with situations where moving the knob a tiny fraction rocketed a loco from stop to full speed - it would be uncontrollable.
There is one system with potentiometer knobs that DOES adjust the system to the loco speed rather than adjust the loco speed. The ESU ECoS system. But they cheat. Ever see high end audio gear with remote controls, but a knob for volume control rather than buttons? The remote controls a motorozed potentiometer that turns the knob. The ECoS system has the same thing. Select a loco running slower than the current knob position and it turns the knob down. Select a faster loco, and it turns the knob up. So much simpler just to use an encoder, like the DT400. An encoder generates an electrical signal to the circuitry when you turn the knob up and down. There is no stop, you can twirl it endlessly in either direction. Thus the position of the knob has no bearing on the speed comamnd being sent to the loco. Simplistically, the encoder acts like a couple of pushbuttons. Push one for faster, one for slower. Only it's a rotating knob instead of buttons - the circuitry behind it is similar to that used by a pushbutton throttle - in fact many encoder throttles ALSO have pushbuttons in case you prefer that - the DT400 does, and NCE's ProCab and PowerCab throttles also have buttons plus a thumbwheel encoder.
"What Rinker said"
Reason I did not go with the Zepher is the problem you are having. It is one of the reason I retired my Bachmann E-Z . You can add a DC transformer to the Zepher so you have two throttles. I went with the Super Empier Bulider because it came with the DT 400 and you can add one to the Zepher.
I was lucky that Simon 1966 brought over his Zepher before I installed mine and found this short coming. So back to K-10 Model Trains and trade it for the Super Empire Bulider, cost of the DT 400 was the same as getting the SEB.
Reason I so happy with the SEB is because of the TH 400.
Cuda Ken
I hate Rust
Thought you were a MOPAR man, what's with the Turbo Hydromatic transmissions?
Cheaper way to "fix" it would be to add a Jump throttle or two. It's still a potentiometer based throttle but you'd have one for each train.
Okay, for starters, anyone who runs a train without any kind of direct throttle control is certifiably insane. This is how accidents happen, and I cannot stress enough how unwise a practice it is...that is, unless you like wrecking your trains. If that's the case, heck, go to it and have a blast. Just, um, stay away from my layout, okay?
With the Zephyr, you do have the 2 jump ports available. If you have a DC throttle or two (from MRC, generally), simply connect it/them to the Z's jump port(s). These DC throttles can be set up using the Z's key pad, and then the assigned locos are under the DC throttle's control. The Z can cycle through each port to access control of functions, but each throttle is still controlling the seperate trains.
For example, say you have a DCC address 1200, and you want to run it on jump port #1 that has an MRC Tech II throttlepack wired into it. Press the "JUMP" button on the Z, and the jump indicator light will show on the LED display. Press LOCO, then enter 1-2-0-0, then hit LOCO again. The MRC throttle now controls address 1200 (speed and direction). Say you have another DCC address 1407 you want to assign to jump port #2 that has an MRC Tech 4. Press "JUMP" again, and the jump indicator will now start to blink. Select 1407, and now this addess is assigned to Jump port #2. Changing the speed and direction of the Tech 4 will now control 1407. To go back to the Z's own throttle, hit "JUMP" again, and the jump indicator light will go out. At this point, you have two trains running on seperate throttles with the Z's throttle still open.
BTW, if you don't have a DC throttle for a jump port, one can build one out of some inexpensive parts if one wanted to.
As for why the Z does this with throttle speed matching, as others have said it's because of the type of throttle they are using. The Z is has the form function it does because Digitrax wanted folks who were comfortable with DC throttlepacks to see the Z as something similar. Since all DC powerpacks have pots for throttles these days, so does the Z.
Now, Digitrax used to offer a speed matching pot throttle called the UT-1 (and UT-2 which was the same thing but with programming features). The UT-1, when selecting a moving train, would have a series of blinking LED's to indicate if one should move the throttle lower (scrolling right to left) or higher (scrolling left to right). They also had a bi-polar LED for indicating direction. If it was red, the direction toggle needed reversed. If it was green, you were all set. The only trick, of course, is that while one is futzing around trying to match the knob to the train speed, you have no control over the train at all. This led to accidents, and this "feature" was not repeated in the newer UT-4.
If one wants a throttle that can simply take over control of a moving train without any issue, then you need a DT-series throttle like the DT100, DT200, DT300, or DT400 (only the DT400 is still in production).
Paul A. Cutler III*******************Weather Or No Go New Haven*******************
Maybe if you don't have a continuous run.. or confidence in your tracklaying. My previous layout had a double track loop so I could let things roll, and I often would run my PCM T1 as background ambiance while I built kits at the workbench. I could run long trains forwards and backwards at warp speed with no derailments, so running at 5 mph was no problem ever. Plus even if it would have rolled completely over, no track was close enough to the edge that it would have fallen to the floor. All this with out of the box Atlas Code 83 track components and flex track. Impossible, some might say? When/if I have the room to build another layout with a continuous run option, I'll be glad to demostrate. Yes, I could run steamers and other complex locos like a GG-1 through the turnouts at full throttle and they never ever derailed. That is my 'acid test', if they can run at warp speed withotu derailing, I am pretty confident they can run at proper scale speed without derailment. I wasn't so trustign that I'd leave the room with equipment moving, but I wasn;t worried that I'd wreck my trains if I turned my back for a few minutes.
rrinker Thought you were a MOPAR man, what's with the Turbo Hydromatic transmissions?
Randy, I wonder why TH 400 sound so familiar to me, from my cars days not that I ever had a one. As you know I ment DT 400.
I think I'll install a jump throttle-that way my son can run a train at the same time. My Digitrax docs say a "smooth DC" throttle will work. What do they mean by smooth DC? One that is not pulsed like an MRC 1500 or one that doesn't "bleed" AC? I have an old Bachman power pack from a RTR set. I was going to hook it up but thought I better check here first in case.
OntarioTodd I think I'll install a jump throttle-that way my son can run a train at the same time. My Digitrax docs say a "smooth DC" throttle will work. What do they mean by smooth DC? One that is not pulsed like an MRC 1500 or one that doesn't "bleed" AC? I have an old Bachman power pack from a RTR set. I was going to hook it up but thought I better check here first in case. Todd
Both. A simple plain train set pack should be fine. There are some super-simple circuits to build one in the Yahoo Digitrax Group files and pictures sections. One potentiometer, one transistor, a resistor, an dpdt toggle, and a 9V battery. Add one more SPST toggle to turn the power off, or always rememebr to remove the battery, it drains out rather quickly if not removed. I built one and used it on my Zephyr with excellent results.