Trains.com

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Soundtraxx Tsunami CV 4 problem with Bachmann Spectrum 4-4-0 (HO)

3200 views
11 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    October 2007
  • 58 posts
Soundtraxx Tsunami CV 4 problem with Bachmann Spectrum 4-4-0 (HO)
Posted by Scale Hogger on Monday, May 9, 2016 7:27 AM

I'm using a Digitrax Zephry Xtra with a brand-new Bachmann Spectrum 4-4-0 (HO) with Tsunami decoder.

Anyone else having trouble setting CV 4 (Baseline Braking Rate)? I'd like to set it at 75. Engine acknowledges change in value, but there's no change in performance afterward.

CV 3 (Baseline Acceleration Rate -- set at 100) and all other CVs work fine. 

One other thing I note is that the engine won't move until the throttle is at 1.5 or higher. CV 2 (Starting voltage) is at factory default of 00.

  • Member since
    February 2002
  • From: Mpls/St.Paul
  • 13,892 posts
Posted by wjstix on Monday, May 9, 2016 2:17 PM

For the latter part, increasing CV2 will make the engine start sooner. I'd start with a setting of say 20 and try that, then increase it if necessary by 10 or 20 until it's where you want it.

For the other part...how does it work now? When you stop the engine, is it coming to a dead stop (like as if CV4 were zero)? Or is there some stopping momentum, but you're not able to increase or decrease it?

Stix
  • Member since
    October 2007
  • 58 posts
Posted by Scale Hogger on Tuesday, May 10, 2016 2:58 PM

[quote user="wjstix"]

For the latter part, increasing CV2 will make the engine start sooner. I'd start with a setting of say 20 and try that, then increase it if necessary by 10 or 20 until it's where you want it.

For the other part...how does it work now? When you stop the engine, is it coming to a dead stop (like as if CV4 were zero)? Or is there some stopping momentum, but you're not able to increase or decrease it?

 ---------
Thx, Stix.
1) I'll try adjusting CV 2 per your suggestion.
2) When I change the Zephyr's direction control to BRAKE, the drivers make about 1 revolution and then stop abruptly. I have tried setting CV 4 (Baseline Braking Rate) to various settings: 50, 75, 100, 150 and even 255. After each change, the loco acknowledges the new setting -- but there is no change in braking performance.
3) I now have a call into Soundtraxx.
  • Member since
    July 2006
  • From: Pittsburgh, PA
  • 1,796 posts
Posted by JoeinPA on Tuesday, May 10, 2016 3:18 PM

The brake function via the brake posion on the Zephyr direction control is independent of the CV settings in the locos decoder. You can set different braking rates for the Zephyr via the program function. Take a look at the manual on about page 20. To use the rate set in CV4 you can just set the trottle to zero or as Digitrax suggests flip the direction control to the opposite direction. I prefer just lowering the throttle setting and allowing the CV4 setting work.

Joe

  • Member since
    February 2002
  • From: Mpls/St.Paul
  • 13,892 posts
Posted by wjstix on Tuesday, May 10, 2016 4:14 PM

Interesting, I used a Zephyr for about 10 years and I don't recall anything about it having an internal momentum setting? I used to use that center-brake setting all the time since I was running a switching layout. I would set an engine to 8-10 MPH and not touch the throttle, just use the direction switch and let the momentum settings have the engine drift to a stop and slowly start the other direction.

Just some off-the-wall "try anything" ideas:

I suppose it wouldn't hurt to check and see that the decoder is set to 128 speed steps - although if it isn't, I'd think that would affect it both starting and stopping...unless the decoder somehow got set to some oddball speed curve or something.

Maybe check CV 66 Forward Trim and CV 95 Reverse Trim and see if they're still at the factory default of 128, and if CV61 F11 Braking Rate and CV 24 Consist Braking Rate are set to -0-. Also make sure F11 didn't accidently get 'stuck' on.

Otherwise you might have to 'bite the bullet' and just do a full factory reset and see what happens. I find Tsunami and other recent Soundtraxx decoders very difficult to set up, and often have to reset them once or twice before everything is hunky-dory.

Stix
  • Member since
    October 2007
  • 58 posts
Posted by Scale Hogger on Tuesday, May 10, 2016 9:01 PM

Thx Joe and Stix! Here's the latest.

Setting the Braking Rate IN THE ZEPHYR (using the MU button) controls BOTH the Acceleration and the Deceleration speed -- and overrides any setting that been done with CV 3 and CV 4 in the decoder. The default setting is 01 (minimal acceleration and deceleration). I find I can live with the result of setting it at 11.

If I set the Zephyr's Braking Rate to 00 (Off), then the Braking Lever doesn't work at all. The only way to stop the loco is to turn the throttle knob to zero or -- in an emergency -- to turn off Power to the track.

Now, what I WISH I could do is simply set CV 3 (startup) and CV 4 (braking) to the separate values I want and have them work from the Forward-Brake-Reverse lever. Apparently, that's not possible unless I have overlooked something. If so, do let me know!

Early on, I did a Factory Reset, checked everything out and started from scratch (loco address and all). I haven't changed the Forward and Reverse Trims.

Again, thanks to both of you. Things are better now, if not quite perfect from my point of view. If I learn something significant from the folks at Soundtraxx I'll post it here.

JHF

  • Member since
    January 2015
  • 257 posts
Posted by RR Baron on Tuesday, May 10, 2016 10:08 PM

 

Scale Hogger,
Decoder uses Speed steps and  throttle setting not Brake position of the Forward-Brake-Reverse lever
CV 4 – Baseline Braking Rate

Braking rate computed as :

seconds/speed step = CV 4 x 0.896 ÷ Number of speed steps

 

CV 3  - Baseline Acceleration Rate
Acceleration rate computed as:
seconds/speed step = CV 3 x 0.896 ÷ Number of speed steps

 

Ref: Tsunami Technical Reference

http://www.soundtraxx.com/manuals/tsutechreference.pdf 

 


Also, 

Digitrax Zephyr  Xtra can be inconsistent programming SoundTraxx Tsunami decoder.
see KB33: Programming SoundTraxx Tsunami Decoders with Digitrax Zephyr

 

RR Baron

 

 

  • Member since
    February 2002
  • From: Mpls/St.Paul
  • 13,892 posts
Posted by wjstix on Wednesday, May 11, 2016 8:31 AM

Tsunamis can be a bit odd, and finicky to program. I had one that would work fine for a while, then for no apparent reason it would "forget" some of the speed CV settings...so I'd have it speed-matched to another engine and when I tried to run them together a few weeks later, they were not longer matched.

I just this year had to send a Tsunami back for repair work because it just quit working - the engine was rumbling along just fine, then stopped dead and the sound died. I got it back and it's working OK - except the lights don't work! I've temporarily added LEDs with resistors/diodes so the lights are on whenever there's power to the track; eventually I'll add a lighting decoder or just use an old non-sound decoder when I upgrade an engine to sound.

Anyway, after using TCS, LokSound and Digitrax sound decoders, I'm unlikely to ever buy a Soundtraxx decoder at least for the forseeable future.

Stix
  • Member since
    February 2008
  • 8,877 posts
Posted by maxman on Wednesday, May 11, 2016 8:50 AM

Why are we calling CV 4 baseline braking rate?  I thought that it was deceleration rate, or deceleration momentum, or something similar.

I think we're all talking about the same thing, but I've never heard it called that before.  Or is that what Soundtraxx calls it?

  • Member since
    September 2003
  • 10,582 posts
Posted by mlehman on Wednesday, May 11, 2016 11:33 AM

Soundtraxx calls CV4 the Braking Rate.

Worth checking CV29 to be sure it's not in something other than in 128 steps. The user guide does note that if using 14 or 28 steps that it's useful to set CV4 higher than 0 for good response as this smooths out the response between speed steps.

Also note that the HIGHER the value in CV4, the longer it takes to stop, as much as "several minutes" if it's set to 255. I usually use values between 12 and 40 or so.

Even if you've done a reset before, if the new values don't seem to have an effect, go for another reset. If this is a problem, you're probably not using DecoderPro, which will store what's supposed to be the CV list and make it easy to update to your local settings.

Mike Lehman

Urbana, IL

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Wednesday, May 11, 2016 12:32 PM

 If adjusting CV3 is makign a difference on acceleration, then the programming is workign fine. If you read back (and you must hit CV-RD, because f the last thing you did was set CV4 to say 20, the display will still show 20 BEFORE you read the CV - this is NOT the value in the decoder itself, this is the last number you keyed in on the Zephyr) and get the expected value, ie, whatever you programmed in, then again, the decoder is accepting the programming and  the issue lies elsewhere.

 Also see Page 21 of the current Zephyr Xtra manual for setting the brake lever. If this has been disabled by setting the brake rate to 0, nothign will happen when you move the direction elver to the brake position. You can test for the CV4 value working by flipping the direction to reverse while at speed, rather than brake. If the loco gradually slows down and then changes direction, the CV4 programming is actually working, and the issue is that the brake ont he Zephyr is probbaly disabled. If it does not slow down and gradually stop before chaning direction, it's a decoder issue. It should also slow down gradually if you leave the direction switch alone and just set the throttle to 0.

                    --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    October 2007
  • 58 posts
Posted by Scale Hogger on Wednesday, May 11, 2016 3:33 PM

Hi -- Yes, Baseline Braking Rate is what Soundtraxx calls deceleration.

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Users Online

There are no community member online

Search the Community

ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!