I am going to call into Soundtraxx support tomorrow, but thought I would ask the group tonight for any clues or things to look for.
The story is that I have a digitrax DCC system with a DB150 command station. I have run pretty much everything with DCC either out of the box or my own installations with no problems whatsoever to this day.
So I decided to try a soundtraxx decoder as people speak highly of them. I wired a diesel decoder and the recommended speaker purchased at the same time from a local train store, into an older bachmann spectrum GP30. Worked for a minute or two then poof. Overheated and that was that. As I was testing it I simply assumed that I shorted a bare wire on something as I was just doing a test before I soldered it all together.
I emailed Soundtraxx support and they said send it in and they will warrenty it. No problem, or so I thought. This was back in December. In February I checked in and they said they were short on replacements for the diesels and were having another run made eventually. I still have not received it.
Ok, so I move on while I am waiting. In the meantime, I went ahead and bought a steam decoder to pop it into my bachmann K4 to replace the digitraxx I had put in it that worked just fine. Easy peasy. Bought a decoder, a speaker, and a 9 pin plug all from the same vendor in person and verified the parts were correct to work together. Simple install. The only actual wiring is the 2 on the speaker.
Plugged it all in and everything worked great! I was very impressed with the sound and low speed control. Ran it for a few minutes slow, fast, fowards, backwards, and so on. Then the speaker started to make a humming sound. Then a few seconds later it was all over. No more sound and melted shrink wrap on the decoder. Huh? Ok, but the motor still works great, just no sound. Put the digitraxx decoder back in and no problems. Tried the soundtraxx and still no sound. Hmmm, ok, maybe some bad luck? So I sent that one in for warranty and got a replacement back quickly. Did all of the same thing as before only even more carefully. Double checking every step. Made absolutely sure there was no way for it to short. Plugged it in and wow! Great! Good sound and motor control. Went forward and back, slow and fast, etc. Had my fingers on the decoder to see if it was warm. Everything was great. Then...
It just started humming again and I quickly grabbed it off the track. Decoder was warm and the shrink wrap in that same little spot was starting to melt. Huh? Guess what? No sound but everything else... I checked and have 13.7 volts at the track in the spot where I was testing. No beeps, no shorts, no warnings. No circut breaker tripping on the chip or on the command station. Tripped the track with a screwdriver and it shuts down correctly and beeps. Now the decoder is still working the motor just fine, just the sound portion blowing up.
For other info, I have bachmann, broadway limited, MTH, and digitrax with sound working just fine, no hums, no hiccups, no nothing. Never anything like this.
So am I just unlucky? Is the product bad? Is there something else wrong that I cannot yet identify? Any ideas? I can blame myself once or even twice, but three times? After being extremely cautious? Anybody got any ideas to throw out? Anybody had anything like this happen to them?
Is this the split frame Bachmann?
http://cs.trains.com/mrr/f/744/p/171822/1886666.aspx
Henry
COB Potomac & Northern
Shenandoah Valley
The diesel was but I was thorough and isolated everything. Both work fine with a digitrax decoder, just not the soundtraxx, thats the wierd part. And the steam loco has an 8 pin NMRA plug in it already, and again, the digitrax works fine. So its not an internal short in the loco. And the motor works fine, just not the sound.
What specific model of Soundtraxx decoder and what specific brand/model of speaker?
Assuming no wiring/insulation errors, you can still burn out the amp if you use the wrong impedance speaker.
As an aside, I've installed a few TSU and TSU2 PNP's in various locos and they've all worked fine.
If one of the speaker terminals or wires contacts the frame, that will fry the amplifier as well. Or it touchs something connected to the track, like one of the tabs on the truck mounting screw in the steamer.
I only ever had one Tsunami, never had a problem running it on my Digitrax system but I prefer the motor control and sounds in ESU, especially with diesels (Tsunami horns are weak), so I traded it for the same loco with an ESU decoder, and I buy nothing but ESU. But while I had it, the Tsunami had no problem running on my Digitrax layout. You DO have the scale switch on the DB150 set to HO or N, right, not O? Your track voltage reading would seem to indicate HO but depending on your meter na dhow you measured, it's a little low for HO and a little high for N. Expensive meters are not the answer here, cheap ones give more accurate readings. Digitrax recommends measuring Rail A to GND, in DC, and then Rail B to GND, in DC, and adding them together. They should both be the same or within a couple of tenths of a volt (less than .5V difference) unless you have address 00 at a speed other than 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.
I don't have them in front of me but I think the speakers were 8ohm. Both were verified by the vendors selling them to me in person. One at a local train shop, and the other at a train show. I also verified the ratings on the package with the instructions. The first decoder, the diesel one, was an economi. The second one was a TSU2200 steam 2 decoder.
The speaker came in its own enclosure. No bare wires but the connections the decoder which was covered. Voltage is 13.7 on HO. When turned up to O, I get 18+ volts
Same speaker used each time? Have you used your meter to verify the speaker's impendance?
Mike
Water Level Route Same speaker used each time? Have you used your meter to verify the speaker's impendance?
One thing to watch is the watt level,of the speaker. The Tsunami2 has a 2 watt auito out put and most sugar cubes are only rated to .7 watts . It is easy to over drive the speaker if the volume is turned up much.
This will damage the speaker- and possibly the decoder.
the Econami has a 1 watt amp, but again watch the volume level
this is the speaker in the steam loco:
https://railmasterhobbies.com/railmaster_hobbies_speakers.htmlRailmaster hobbies DS1436-8: 8 ohm, 1.5 watt, 14mm x 36mm x 10mm(0.55” x 1.41” x 0.39”). Comes with ported enclosure.
Checks out at about 7.7ohm on my meter
I spoke with soundtraxx and they dont have any ideas either, but the issues I am experiencing can be pretty much narrowed down to the speaker leads. All I can say is that somehow it is theoretically possible the wires touched something or each other even though I did everything I could to protect them...I have one more coming to test and I am going to setup a test with nothing else possible to intefere on a short section of track isolated from everything else, with every single wire carefully shrink wrapped etc. If I get through this time it would have been some simple mistake I made somewhere. If not I am at a loss where to look. Will update the thread next week with the results.