LionChief Curcuit Board with 4 Ohm load?

Perfectly logical reasoning for this application.

I was joking about the Spikes.  I don't believe they are of a long enough duration to cause excessive heating in the cap, ie failure.

The bottom of my AC/DC Buck Converter board is different than the one represented on the order page.  On the one I received, the DC Input appears to be incorrectly labeled AC Input and the large capacitor is connected differently (unless I am looking at it wrong?).  Take a look:

Depicted

What I received:

John

I would put AC or DC in on the AC terminals.  Since it's a full-wave bridge, it'll handle DC just fine on the AC terminals.

@gunrunnerjohn posted:

I would put AC or DC in on the AC terminals.  Since it's a full-wave bridge, it'll handle DC just fine on the AC terminals.

Thanks John.

Good to know.

And in terms of a current keeper capacitor to be clear I could solder that to the bottom right where I labeled Lg Capacitor on the photo above.  Is that correct?

John

Yep, right across that large input cap, make sure you get the polarity correct.

@gunrunnerjohn posted:

Yep, right across that large input cap, make sure you get the polarity correct.

Of course.

Thanks again John

John

@Craftech posted:

Update:

Here's where I am with this experiment.

1.  Definitely louder sounds with either the HiLetgo or Adafruit mini amps with a 4Ω speaker (tried two different ones) powered by an AC/DC Buck converter.   Seems to work the best without any attenuation on the Lionel amplifier speaker outputs.  Input level can be controlled with the Lionel remote.  Both mini amps also have trim pots.

The problem with it is that there is an interruption in the sound when it goes across the insulated sections of the FasTrack switches (see below)

Those are necessary to prevent shorts with certain wheels (Example:  Lionel Santa Fe Super Chief RTR set).

The only way to combat the interruptions would be for me to install a second pickup on the other truck which I really don't want to do.  Maybe someone else someday may want to try that.  Frankly I have had it with messing with mini amps inside this thing.

I removed all of it.

2.  So then, despite the warnings about overloading the Lionel amp I tried two different 4Ω 3W speakers in place of the stock 8Ω speaker and guess what?  It made no difference in the loudness at all.  Neither 4Ω speaker was any louder than the original 8Ω speaker.

So I back went the original setup with the pill bottle baffle for placebo effect.

I may try an 8Ω 0.5W speaker for the heck of it.  The aforementioned SF RTR set has one of those and sounds great.

Thank you everyone for all the help with this project. 

John

UPDATE:  Tried an 8Ω 0.5W speaker (with the baffle).  Again, no difference in loudness, just a slight reduction in base response.

Will try the amp with the current keeper capacitor next.

John

Sad follow-up.

Grandson's original amp board fried.

Was able to use the HiLetgo amp fed by the AC/DC buck converter with a current keeper cap as mentioned above.  Using an 8Ω speaker (original) it sounded great and no interruptions going over switches.  Adjusted the pot on the amp to reduce the level feeding the speaker (no pad on the input from the LC engine amp) and it was plenty loud.  Better than ever.  So I ran it for awhile.

Then it derailed at a switch and shorted out popping the Sensata breaker connected to the Z1000 (usually not a problem).  Just reset it.  There are also a TVS diode attached to each end of the two loops.

Except now there is no sound at all even when put back at the stock configuration.  No Bluetooth chirp - nothing except a hum.  When Bluetooth remote is turned on the engine moves forward and backward, but the sounds are gone.  Tried the Bluetooth app on a tablet - no sounds with that either.  So engine controls work, Bluetooth works, sound does not.

Unless there is some miracle anyone knows about I am assuming I have to open up the Lion Chief engine and replace the entire amplifier board.

I knew the risks when I started this project.  My grandson is coming tomorrow so I'll let him know what happened. 

Thanks,

John

I doubt there's a miracle in the offing.

@gunrunnerjohn posted:

I doubt there's a miracle in the offing.

I think the board is $75.  I just have to find disassembly instructions.

Thanks,

John

John sorry to hear about the accident.  Good luck replacing the LC board.  Who knows, maybe the new one will be louder...

@SteveH posted:

John sorry to hear about the accident.  Good luck replacing the LC board.  Who knows, maybe the new one will be louder...

I thought of that.  At least others who find this thread will have an idea of what one faces ahead of time.

Thanks,

John

Increasing the sound volume on a Polar Express that is on a Christmas layout prompted me to go through this post. Since its been over a year, has any new hardware or ideas on how to accomplish this shown up?

TVS are connected to pickups on all my locos that have circuit boards as well as AirPac breakers on the ZW.

I was thinking of adding a speaker, Buck Converter and amplifier to a passenger car just behind the tender and putting a tether that connected the tender speaker output to the  passenger car amplifier input.

@Santa Bill K posted:

I was thinking of adding a speaker, Buck Converter and amplifier to a passenger car just behind the tender and putting a tether that connected the tender speaker output to the  passenger car amplifier input.

Keep in mind that it's likely that any amplifier power supply would have to be totally electrically isolated from any track ground or power.  A common ground is unlikely considering the way that most speaker amplifier circuits are designed on our model train electronics.  Power is an important consideration in a project like this.

Considering using the Buck attached and the Stereo amp attached with one 1.5" speaker (not sure that the 2" would fit in the bottom of the Polar Express passenger car) for each channel and sending the same input to both of the channels.  I think that 2 speakers and the amp would provide plenty of volume. On the grounding consideration: The Buck would be powered by the same pick up roller as the lights in the passenger car and the ground from the wheels same as the lights. The Buck would power the amp. The input signal would come from the speaker connection in the Tender.  The amp input impedance should be high enough to not have much affect on the output of the Tender amp. The Buck and amplifier would be isolated from the frame of the passenger car. A new tether made of the small power connectors that you frequently refer to will carry the audio signal from the tender speaker to the stereo inputs.

LED upgrade is already in the passenger cars. (Rod's kits)

Would this provide the adequate ground isolation that you are referring to?

Any suggestion on using different parts?

Thanks for sharing you wise council.