AML GP60 mods & improvements

 There's a number of little things I have seen that can be addressed:

• number board lighting bleeds into cab
• blue-white leds all over
• Cab light LED grossly visible from outside
• Kadee coupler conversion
• additional speaker in tank
• wiring change to allow shell to separate
• rewire track pickup wiring and addition of PolySwitch PTCs to protect from shorts

Wiring changes to allow shell to separate from chassis

All the wires between the shell and the chassis have a way to disconnect EXCEPT the wires from the ditch lights, which originate on the chassis, but then go into the shell/cab, and then the wires plus more wires go back to the chassis through a plug.

Below is the chassis side showing the wires from the ditch lights. You can see the 4 wires turned into 3 (combining of 2 blue LED common):

I added a 3 pin "micro fit" molex connector on the 3 wires between the chassis and the shell. Make sure you don't mix up the black wires, so your left and right designations in the socket are still correct.

Wiring changes to add short circuit protection

From bitter experience, I decided to add PolySwitches (3 amp solid state circuit breakers) to each track pickup lead to protect the internal wiring and pickup wiring in case of a short. (derailments on a switch often can cause a short between trucks).

I also took the opportunity to use both motherboard connectors, the front and rear ones for the track pickup connections. (the front and rear wires for both trucks were bundled together and used only one of the 2 track pickup sockets on the mother board.

The polyswitches are small enough they can fit through the hole in the chassis, so an added benefit is to allow removal of the trucks without unsoldering or removing the weird gray wire nuts.

Here's the system re-wired to have the track pickups for the trucks separated, by disconnecting the original wiring, and adding 1 more 2 position micro-fit connector, and using X1 and X14 on the motherboard. (this is not soldered yet until I confirm polarity for DC and DCC. I will add polyswitches on all 4 connections you see.

Blue-white LEDs

WTF? Really? in 2024?? So I have not decided if I will replace the LEDs with warm white, or cover with Tamiya yellow. Unacceptable 10 years ago. Absolutely nuts.

Contain number board light, and cab light reposition

Additional speaker in tank

Since I use decoders that have 2 speaker/amplifier outputs (and can route different sounds to different speakers) I will add another speaker in the fuel tank, since it is empty. I have not done this yet, but might actually use 2 speakers in parallel to really get some bass. (I do the prime mover sounds and spitters from the tank, and bell and horn from the speaker in the top.

Misc info:

Camarillo Pacific makes the Campac coupler box for Kadee mounting, and it adjusts to get a precise coupler height.

https://www.camarillopacific.com/wp-content/uploads/2023/08/AML_GP60_CampacInstall_Instructions.pdf