Lost Address

[geejbee]

Good evening,

I have a TTS decoder fitted in my Tornado which generally works very well. However, all might be fine for say three days then on the fourth its a case of no go except I believe the sound functions still work. If I then re-program the address, all will be fine again for an indeterminate period of time.

Can anyone tell me what is causing this annoyance please.

[Chrissaf]

Do you get any instances of very brief transient short circuits. On DCC, these type of short circuits cause ringing (a form of runaway oscillation). This can cause decoders to lose their configurations or have them corrupted. Re-addressing then needed to recover or if severe corruption a CV8 factory reset. Very severe 'short circuit ringing' cases can permanently damage the decoder or just make then weak and susceptible to continually loosing their configuration [compared to other locos on the layout].

 

The theory of this and a suggested fix to reduce the ringing effect is described and detailed on this website written by Mark Gurrie a member of the NMRA. In particular, read Section 2 of the linked page.

 

https://sites.google.com/site/markgurries/home/dcc-general-best-practices/wiring-planing/snubbers-rc-filter

[geejbee]

Hello Chrissaf.

By "brief transient short circuits" do you mean the kind of situation where say a derailment somewhere on the layout causes the select controller to trip out, because I have had that happen in the past but couldn't say that this had an immediate affect on the tornado.

[Chrissaf]

You can also get transient short circuits that are so brief that the controller doesn't get a chance to fully trip. A metal wheel for example bridging opposite phase rails as it passes through a point. It doesn't have to be a full derailment.

[geejbee]

Blimey, it gets a bit complicated doesn't it.

[ColinB]

There seems to a lot of issues with TTS. My most recent one TTS in dummy HST 125, working perfectly ok when I last used it, suddenly no sound. So I did the usual, checked speaker connections etc, etc, did a ton of tests in tester. Suddenly it started working, until I switched the DCC on and off (didn't even touch the loco), this is on top of one that every so often would lose its sound. I have got to the point now where I am checking all my locos with them in. There is either something very suspect about the way they set things in their software or some very suspect hardware. I use them because they are good value for the money, but I am beginning to think is it worth it? The one that kept losing sound seem to be an interaction with the loco motor, replaced it with an expensive Zimo one, put the original TTS in another loco and it worked ok, but who knows what will happen in a couple of months time. The annoying thing is when they work they sound ok.

Sorry don't agree with the short circuit explanation, that would be the power side of the decoder, the electronics within the decoder should handle that. The only issue you might get is multiple resets on the decoder micro which if not programmed properly could put it in an undefined state.I assume what he is refering to is, if the decoder has "on board" memory and is writing to it when it gets a reset, but it should only be reading from it in run mode. I will read what he has to say though.