Spectrum steam engines and DCC sound

[charliek1932]

Our club members have several Spectrum steam engines either DC, DCC and DCC with sound. All our track is Atlas. The DCC sound engines have problems going over the turnouts. Every engine stops will die at a turnout, reset itself and then take off. This happens intermittently and not at the same turnout. The engine can run for several loops and then do this at a different turnout. We have cleaned the engine and the turnouts and it still occurs. All our non DCC sound engines do not have this problem. Broadway Limited and other manufactures do not have this problem. Any suggestions?

[richg]

The Tsunami do have this issue occasionally.
Sometimes, it is the frog, sometimes intermittent pickup, sometimes spots of dirt on the track or not so clean drivers.
On my Spectrum steamers, I installed all wheel pickups and the factory tender trucks pickup only on one side of each.
The Tsunami that you install yourself comes with a stay alive cap but some people install more capacitance for this issue.
About the factory installed Tsunami, I have no idea of how to install more capacitance.
I do not know if anyone has hacked the factory installed decoder at this time.

My diesels with all wheel pickup and Tsunami I installed do not have this issue.

Below is an article on this issue.

Click on Loco Stay Alive.

http://www.members.optusnet.com.au/nswmn/index.htm

All I have read seems to indicate intermittent pickup somewhere.

Rich

[Thomas1911]

I have been experiencing a similar problem with my Tsunami-equipped Spectrum steam locos.  I also have this problem with my Proto 2000 SD7's and Athearn F7's, all equipped with Soundtraxx DSD decoders.  I have Atlas #6 turnouts and all of my locos will stall intermittently, but always at the frog.  I do have a few #4 turnouts as well, but they have not been a problem.  I noticed that the frogs were slightly higher than the railheads on all of my #6 turnouts by approximately 1/64", checking with a straight edge laid across the turnout at the frog.  This was causing the wheels of my locos to lift from the rails and lose power.  I also searched the Atlas forum and found others with this problem.  My fix was to use a flat file to level the frog with the rails.  This has significantly helped the problem, but not completely cured it.  I think the guardrails may be the rest my problem as they were a little wide when checked with an NMRA gauge.  I haven't had an opportunity to test my hypothesis as of yet. 

[Jim Banner]

I have not experienced any of these problems with the Tsunamis in my 0n30 locomotives, neither in the ones with factory installed sound nor with the ones I have installed myself.  I suspect it is because I use all metal turnouts.  If so, then powering the isolated frogs used in Atlas turnouts may well solve the problem.

The article Rich linked to makes a lot of sense from an electronics point of view.  The only questionable point was comparing the keep alive capacitor in a Sountraxx decoder to that in a Lenz Gold decoder.  In the Lenz decoder, the keep alive capacitor continues to power the decoder even if contact with the rails is lost.  Other circuitry in the decoder maintains communication with the command station when contact with the track is lost.  With a large enough capacitor, or better yet, a battery, you could run an engine equipped with a Lenz Gold decoder all day without ever making contact with the rails.  With other decoders, increasing the keep alive capacitor or adding a battery will power the motor only until the packet time out (in CV11) is exceeded.  Then the decoder will turn off motor power no matter how much power is available.  I am not sure if packet time out plays a part in the stalling and restarting that people are noticing or not.  The Tsunami Technical Reference Manual lists the default value for CV11 as 0 which should set the packet time out to infinity.  Programming CV11 to a value of 0 to make sure that it is actually zero may help with the problem and certainly will not hurt anything.

Jim

[scotthight]

My Spectrum USRA 4-8-2 Mountains (2) stalled on the frog of some of my Walthers Shinohara DCC friendly turnouts. Bachmann was kind enough to exchange the Mountains for Consolidations, which have no problems with the turnouts. Now, unfortunately, I find the Tsunami sound in the new Consolidations is much 'tinnier' and shallow-sounding than the Tsunami sound in my older Consolidations. I've looked at the sound install in a new and an older tender and can't see any difference. I've reset the Tsunamis back to factory defaults with no improvement in sound.

[digitalgriffin]

Most of these issues are related the turnouts NOT being dcc friendly, or not wiring up the frog itself to the switch machine.

What happens is with non dcc switches is that sometimes the rails short and then the train doesn't get power (power goes straight to ground instead of going through the locomotive)  The Soundtraxx Tsunami does NOT have a very large capacitor like the QSI engines.  So it doesn't have the energy reserves that the large when a short happens.

With DCC friendly turnsouts, you have two types.  Live frog (electro frog) and insulated frogs.  With electro frogs (the best there is to use with short locos), you have to wire the frog to the switch machine relay.

Please read the following article about DCC switches.

http://www.wiringfordcc.com/switches.htm