I have an Intermountain F3A and F3B consist that until recently had DZ143PS non-sound decoders that I installed a few years back.
Recently, I purchased a LokSound Select sound decoder from Intermountain and installed the decoder in the F3A loco.
The problem is that the LokSound Select decoder is factory programmed to start up and stop prototypically. But the DZ143PS starts up and stops immediately upon command. The result is that the F3B drags along on start up while the F3A gathers speed. Conversely, the F3B fights the F3A upon stopping as the F3A continues at a higher speed.
So, I need to match CV values to the extent that is possible. My problem is that I have never mastered CV functions. I have no idea which CVs affect prototypical start up and stop procedures.
Can someone more experienced offer some help and advice? Is the speed table part of this process?
Rich
Alton Junction
Loksound defaults have a bit of momentum in them so you can get the primer mover to load. It might be as simple as putting some non-zero value in CV3 (and 4 so it doesn't keep pushing when stopping) so the DZ143 starts up more slowly.
The other thing to check - by default, Digitrax decoders are set so that when using advanced consisting, there is no BEMF. That usuall translates into the decoder needing higher values in CV2 for the start voltage to get it moving on lower speed steps. To have the same BEMF setting standalone as well as in consist, you need to read CV57 and then adjust it as follows:
If it's 1, make is 17. If it's 2, make it 34. If it's 3, make it 51, if it's 4 make it 68, if it's 5 make it 85, if it's 6 make it 102, if it's 7 make it 119, if it's 8 make it 136, if it's 9 make it 153
(don't ask unless you want to learn hexidecimal numbers)
That may help - or maybe you already did this way back. If CV57 is already something other than 1-9, it's been done.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thanks, Randy, I will run down to the layout and copy the relevant CV values for both decoders and get back with the results.
Loksound decoders have a start delay feature if the sound is turned on. You may also want to disable this feature so it will start moving immediately upon throttle advancement.
Set CV 124 to a value of 16 to turn it off.
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
Rich,
If, even after tweaking, you can't get the Digitrax decoder in the B-unit to work to your satisfaction with the Loksound Select in the A-unit, you could always purchase a Loksound motor decoder for your B-unit. At the very least - turning off momentum in the A-unit should help considerably.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
Mark R. Loksound decoders have a start delay feature if the sound is turned on. You may also want to disable this feature so it will start moving immediately upon throttle advancement. Set CV 124 to a value of 16 to turn it off. Mark.
tstage Rich, If, even after tweaking, you can't get the Digitrax decoder in the B-unit to work to your satisfaction with the Loksound Select in the A-unit, you could always purchase a Loksound motor decoder for your B-unit. At the very least - turning off momentum in the A-unit should help considerably. Tom
rrinker Loksound defaults have a bit of momentum in them so you can get the primer mover to load. It might be as simple as putting some non-zero value in CV3 (and 4 so it doesn't keep pushing when stopping) so the DZ143 starts up more slowly. The other thing to check - by default, Digitrax decoders are set so that when using advanced consisting, there is no BEMF. That usuall translates into the decoder needing higher values in CV2 for the start voltage to get it moving on lower speed steps. To have the same BEMF setting standalone as well as in consist, you need to read CV57 and then adjust it as follows: If it's 1, make is 17. If it's 2, make it 34. If it's 3, make it 51, if it's 4 make it 68, if it's 5 make it 85, if it's 6 make it 102, if it's 7 make it 119, if it's 8 make it 136, if it's 9 make it 153 (don't ask unless you want to learn hexidecimal numbers) That may help - or maybe you already did this way back. If CV57 is already something other than 1-9, it's been done. --Randy
On the LokSound Select, the values were as follows:
CV2=2, CV3=4, CV4=56, CV5=255, CV6=88.
CV 57 had a zero value in both decoders.
Since the adjustment in the value of 124 in the LokSound Select did the trick, I decided not to mess with the other CV values.
CV 57 has a different meaning in Loksound, that was for Digitrax. Do they STOP together? Because with those CV settings, the Loksound has a good bit of deceleration momentum (CV4). It's also implementing a 3 step speed curve, CV5-255 means the top speed is unmodified, but CV6 = 88 is putting the mid throttle speed at something below the middle of the speed range, which would be 127. Now, if they are reasonably close across all speeds, I wouldn;t worry about the CV2-6-5 settings, but I suspect that if you throttle up then quickly turn it down, the Loksound one will want to keep pulling the Digitrax one since the Loksound has deceleration momentum and the Digitrax does not - the Digitrax will stop immediately while the Loksound will continue going and 'coast' to a stop. This would only be noticeable on abrupt throttle changes, if you just slow down one click at a time the momentum doesn;t come into play. On Loksoumd, you need some momentum for it to be able to generate the brake squeal sound. There is a configurable threshold where if you throttle down faster than that setting, it will play the squeal, if you slow down slower than the limit, it will just slow down and there will be no squealing brakes.
Isn't this fun?
Yeah, loads of fun..........................not.
I spoke too soon.
Yes, the locos run in unison when slowing turning up or down the speed, but you are correct. A quick speed up or quick slow down results in an immediate response from the B unit, but the A unit takes its time.
Now what?
Do I swap the Digitrax decoder for a non-sound LokPilot?
Or can I make the two decoders, LokSound and Digitrax, compatible?
Add some momenttumn to the Digitrax. A little bit - 2-4 in CV3, since the Loksound doesn't have much there. More in CV4 for deceleration since the Loksound already has pretty much. And you may have to set CV6 mid speed in the Digitrax to bring down the middle speed. Try a similar value to what the Loksound has as a starting point.
Or get a Lokpilot and assuming you set the motor control parameters the same (or use the auto adjust, one at a time), set the other speed control CVs exactly the same and they should be VERY close, differing mainly due to manufacturing tolerences assuming Intermountain never pulled a Walthers and put different gear ratios in the two units.
rrinker Add some momenttumn to the Digitrax. A little bit - 2-4 in CV3, since the Loksound doesn't have much there. More in CV4 for deceleration since the Loksound already has pretty much. And you may have to set CV6 mid speed in the Digitrax to bring down the middle speed. Try a similar value to what the Loksound has as a starting point.
I reset the values of CV2 and CV4 on the Digitrax non-sound decoder of the F3B.
I only changed the value of CV2 from 2 to 3.
But, CV4 took a little more work on my part. I started on by matching the value of the LokSound at 56. LOL That took forever for the B unit to stop. Changed the value to 28, then 14, then 7, then finally 8. Perfect!
Randy, as always, thank you so much for your help and advice.
Incidentally, I should be embarrassed to admit that after 11 years of DCC, it took me this long to pay attention to the values programmed into CV2, CV3, CV4, CV5 and CV6. I had always been satisfied with factory defaults that set these values at zero, and I got frustrated with factory settings that were programmed for prototypical performance. Kind of a throw back to my American Flyer days as a kid.
richhotrainI had always been satisfied with factory defaults that set these values at zero, and I got frustrated with factory settings that were programmed for prototypical performance. Kind of a throw back to my American Flyer days as a kid.
LOVE prototypical performance. More important than sound, IMO.
I don't always add momentum to my locomotives; choosing to use the incrimental buttons or thumbwheel on my Power Cab to move from step-to-step. I do like the slight hesitation with the Loksound decoders before the locomotive starts out - particularly the steam and the release of the air brake. Nice touch.
Yes, there is no true standard for how much momentum you get for the value of the momentum CVs - Loksound is a bit confusing since they mention two different values in the manual, Digitrax has their formula in their big decoder manual. I know from experimenting when I first got DCC that values much over 16 or so for Digitrax are nearly useless as it takes way too long to start or stop. For grins I set it to the max, and on my little loop of track it went around a dozen or more times before stopping. Loksound clearly is usually a formula that yields less momentum per a given value, since they use 56 where it took you only about 8 to get a similar effect with Digitrax. I THINK Digitrax uses the NMRA RP formula, or close to it. (this all came up in the thread about the two Loksound locos not having the same deceleration momentum)
rrinker Yes, there is no true standard for how much momentum you get for the value of the momentum CVs - Loksound is a bit confusing since they mention two different values in the manual, Digitrax has their formula in their big decoder manual. I know from experimenting when I first got DCC that values much over 16 or so for Digitrax are nearly useless as it takes way too long to start or stop. For grins I set it to the max, and on my little loop of track it went around a dozen or more times before stopping.
Yes, there is no true standard for how much momentum you get for the value of the momentum CVs - Loksound is a bit confusing since they mention two different values in the manual, Digitrax has their formula in their big decoder manual. I know from experimenting when I first got DCC that values much over 16 or so for Digitrax are nearly useless as it takes way too long to start or stop. For grins I set it to the max, and on my little loop of track it went around a dozen or more times before stopping.