ps-2 tinplate engine, no sounds

If it,s running ok it,s probably the audio amp is blown , but can be repaired by n mth  asc tech ! all it takes is a track short or drailment to blow the amp ! Alan

If this engine has a tether, it could a bad solder connection that needs touching up in the loco as you had intermittent sounds previously. Could also be a broken wire in the tether. I would check this out first.

Also, check the battery. I read that it runs. When the battery gets weak all kinds of things can happen.

Look at the speaker for flaking magnet.

@Engineer-Joe posted:

Also, check the battery. I read that it runs. When the battery gets weak all kinds of things can happen.

Look at the speaker for flaking magnet.

Good points, I haven't opened the tender yet.

thanks Gentlemen.

If the resets work and such the battery is probably ok.  Bad Speaker, broken speaker wire, tether IF board in different location then speaker.  Not normal except PS-2 5V.  Audio amp.  G

Finally had time to dig into the tender.  Wow, what a pain! I have been into mth tinplate tenders before,  but this early model was a  challenge.

The speaker was mounted to the bulkhead.  This was different. Getting the shell off is usually either a slide or two more screws away, and then a slide.  In this case there were 4 screws, all of which were buried under the trucks.

Turns out everything around the speaker is glued in place.   The hot glue gun will need to come out for reassembly.   Fortunately,  the speaker looks good,  no flaking.

About this time my phone died so I stopped taking pictures. I figured the tender will get a new battery since it's open.   In the process of unplugging battery,  the battery end of one the moles connector wire came loose - o well,  a new battery and will take care of that anyway.

Also you can see 2 yellow wires nuts.  That's because the third one fell off!  The wires undercut were barely touching and contaminated with some type of glue that was helping hold the wire nut on.  These two wires will probably get soldered together and coated with liquid electrical tape, that's just how I usually deal with tight spaces.   Hopefully after taking care of these loose connections everything will be back to normal.

Put a Volt meter on the 2 speaker wires in the center of the 12 pin connector,  does it read about 4 ohms.  If not.. speaker or a solder joint along wire at the connector is bad.  Test speaker at the terminal.  If good, sounds like audio amp unless the 12 pin connector not fully seated.  G

@GGG posted:

Put a Volt meter on the 2 speaker wires in the center of the 12 pin connector,  does it read about 4 ohms.  If not.. speaker or a solder joint along wire at the connector is bad.  Test speaker at the terminal.  If good, sounds like audio amp unless the 12 pin connector not fully seated.  G

Thank you. I will test the speaker separately first since its unplugged and then trace it back to the 12 pin connector and test again after its plugged in and let you know what I find.  I already ordered the new battery.

JHZ563

@GGG,  How precise does the 4 ohms need to be?  I got 5 ohms at the speaker itself, the speaker plug, and the 12 pin plug.

Images of the board stack mounting set up.  Given the small space in the tinplate tender the board is mounted inverted.   Getting the 12 pin plug loose for an ohm check on the speaker last night was tricky.  The plug seemed to be fully seated. 

Not being an electronics gut, I am not sure which component is the audio amp.  For right now the plan remains the same - get new battery, reconnect loose wires found under the one wire nut, check the connection under the other two wire nuts, and test again.  Maybe I will get lucky.

Usually they read around 3.8.  But 5 ohms should work.  G

@GGG posted:

Usually they read around 3.8.  But 5 ohms should work.  G

Thank you. 

Well,  finally had time to get back to this.  No joy on the super obvious .   New battery and reattached the wires that fell out of the wire nut.   Still response to remote but doesn't make a sound.  Start up, shut down,  smoke and direction work fine when starting through dcs, just no sound.

What does this audio amp look like,  and can I change it myself?  I don't do circuit board soldering, so if it needs off the board, I need help. @GGG I will send you an email.

@jhz563 posted:

...

What does this audio amp look like,  and can I change it myself?  I don't do circuit board soldering, so if it needs off the board, I need help. @GGG I will send you an email.

See this OGR post which has a photo of the audio amp.  There is related info in the thread.  While the part itself is only $3 or so, the soldering job is not a walk in the park.  Send it to GGG.

Got my boards back from @GGG about 2 weeks ago and just had time to finish getting them installed.   The audio amp was it.  Thanks GGG!!

You are welcome. G