PS2 or PS3 transplant into TMCC engine

I'd buy the PS/3 diesel upgrade kit if it were me.  You'd have to replace the TMCC bulbs if you used PS/2 in any case, PS/2 uses all 6V incandescent bulbs except for markers which are LED and TMCC used 12-14V bulbs.  You can probably use the existing striped wheel, but you have to use the supplied tach reader with the DCS upgrade kit.  The PS/3 diesel kit has wiring for every light imaginable.

PS/3 speakers are 4 ohms, so you'll need a compatible speaker. The kit comes with a 2" speaker, but I'm pretty sure the slim speaker that fits in the Atlas is a different form factor.  You have to change the couplers as well as PS/2 or PS/3 couplers and TMCC/Legacy couplers are not compatible.

Many thanks GRJ.

So, are these kits a white whale?  I can't find them for sale online.

Ron,

Just wanted to chime in on the speaker thing...If I understand correctly, you can use a speaker with 4 ohms or greater for the PS3 guts. Even though it says you need a 4 ohm speaker, using a speaker with higher impedance just diminishes the output a bit.

And from my practical experience recently, I have an 8 ohm speaker in a recently installed PS3 system, and I can't tell the difference at all. I don't blast my speakers super loud, so maybe if I tried to increase volume it would make a difference, but I wouldn't have ever noticed.

However, using a speaker with less impedance can overdrive the amp on the board and maybe burn out the amp.

Also, yes those kits are a white whale. I frequently check MTH site, and literally every time I check they're out of stock. Going on a couple years.  Guys on here insist that they frequently restock and you will get an email, but never happened for me. I just wait to find a deal on an existing loco with the guts I'm looking for and rip those out.

I have done Atlas Diesel conversions and they used LED.  They had small boards to work the LED with the TMCC outputs.  You could use the flywheel to register with tach, but if your concerned about scale speed, add the MTH tach tape.  The couplers must be changed.  If they are a unique Atlas type mount, the MTH won't work and you will have to do without coupler control.  Smoke can be integrated too.  You will want a 4 ohm speaker for volume.  G

@GGG posted:

I have done Atlas Diesel conversions and they used LED.  They had small boards to work the LED with the TMCC outputs. 

George,

This Atlas engine has these little boards.  I was hoping to keep all of the existing lighting.  Since these boards are present could I just connect the existing lighting to the appropriate board wires for lights?  There is even a switch in the engine that can manually change the class lights from white, green, red.  I would love to keep that feature in place.

vr
Ron

Those boards were taking AC from the R2LC and changing it to DC for the LEDs.  So you can't connect the PS-3 wires.  You would need to remove components/cut traces and then wire correct polarity to the LEDs.

The ones I converted were not that elaborate to change Class light color.  They did use Forward direction light to operate front HL and rear classification and vice versa so that the Class lights went on and off depending on direction.

You have to study the PCB to figure out if do able.  G

@GGG posted:

Those boards were taking AC from the R2LC and changing it to DC for the LEDs.  So you can't connect the PS-3 wires.

But what about the PS2 board?  That one typically uses the incandescent lights.  If I use that, would these Atlas light boards be doing their job of converting the AC to DC or do I have the same issues to resolve as you described above?

vr
Ron

I don't know.  PS-2 is sending 6V equivalent.   You need to draw out the schematic of the PCB.  What resistance, where are the diodes, and caps.  Gets involved and time consuming.  G

George
If Ron wanted to keep the switches to change the marker lights, could he run the small boards directly off track power since that is what the R2LC provides in conventional (and half wave in command)?  He would, of course, lose the ability to control the marker lights with DCS.  

Bob