Robert, sorry. I used the term "full stop" to stop the thread because I understood my mistake. My DCC controller "Intellibox II" made by Uhlenbrock (a German company) has two built in throttles that display the actual step they are sending (0 to 126). I use them seldom and forgot to use them to see the actual step instead of the UT and guess the step. My decoders are usually set to CV2 = 0 but I learned that the Bachmann GP7 with Tsunami sound decoders start moving around step 20 - 25. That is roughly around 9 o'clock. It set CV2 to 4 and the engines start now at a tad after 8 o'clock with step 5. That is perfect for me.
The IB II handbook in english if you are interested in more details
http://uhlenbrock.de/de_DE/service/download/handbook/en/I4B050BD-03E.apd/Bes65100-01e.pdf
Reinhard
Have you adjusted CV5 and/or 6 or laoded a custom speed table?
My Ut4 throttle sends speed step 1 around the 8 o'clock position. Most of my locos will start moving at step 1 with factory settings; however, once I adjust CV5 and 6 to slow them down, then they often will no longer start at step 1. I assume this is because when they interpolate the speed steps, step 1 ends up being less than .5 causing it to round down to zero. It sounds to me like the decoder is seeing speed step 1 and starting the sound, but when it actually determines what speed step to run at(due to the decoder settings) it comes up with 0 and so doesn't move until the throttle gets to speed step 2 or higher.
farawayFull stop!
No, there is no seperate "full stop" command. There is simply "stop" or speed step 0, and speed steps 1-126, assuming 128 speed step mode (there is an "emergency stop" command, but the UT4 throttle does not send that command).
farawayI got another throttle that displays the step from 0 - 255
What throttle would that be? If it is showing you 0-255, then it is showing you what it is reading from the potentiometer, not what it is sending to the command station, because it cannot send a speed command greater than step 126.
If you have JMRI, then you can see exactly what the throttle is sending by using the LocoNet -> Monitor Slots command. It will, however, show speed step 0 for stopped and step 2-127, and never show "step 1". This is because the binary equivalent of "speed step 1" is the emergency stop command (when it is showing 2-127, it is really step 1 - 126).
Full stop!
I got another throttle that displays the step from 0 - 255 in effect and you are right. Even the most sensitive emgines does not start at step 1. The Tsunami decoder starts the motor about at step 20. That matches the 9 o'clock position.
Case closed, my fault.
Thanks for the reply.
I agree. The throttle has no problem but I am courius how it works :-)
I made some tests with my must sensitive engines and several different decoders and decoder settings but no motor start before the knob is in the 9 o'clock position. That is ok with me and no problem at all!
But what sends the throttle at 8 o'clock position that makes the sound start? That is also very welcome and a nice function but I am courios how the DCC system works in that area.
I assumed the UT4 can only send step 0 - 255, direction and the function keys.
May be there is something between "off" (7 o'clock) and "step 1" (9 o'clock) at 8 o'clock?
I don't think the throttle has a problem. The motor needs to over come the engines weight and friction. Maybe you could program in a custom speed curve that has the first step quite high. But then the engine might lurch instead of starting smoothly.
The most left position of my UT4 is at about 7 o'clock. All engines start at about 9 o'clock. No indivdual setting of the decoder (e.g. CV 2) makes an engine motor start moving prior to the 9 o'clock position.
I assume the UT4 signals at that position to go from step 0 to step 1.
Observation: My Tsunami sound decoders activate the sound when I turn the knob to 7:30 - 8 o'clock positon. The motor starts like all other decoders at about 9 o'clock.
Question:
What signals UT4 at about 8 o'clock that is not a transition to step 1 but triggers the sound of the Tsunami sound decoder?