Pinout for this NCE decoder?

[daniel_leavitt2000]

I have this old NCE decoder that was torn from it's wires years ago. Since it's probably dead anyway, I thought this may be good practice for a reflow hot air station I may get soon.

Trouble is, I don't know what the pinout is. The decoder is not on the NCE site, but looks pretty close to an N12NEM, their decoder for the 6 pin NEM socket. The rest of the N/Z/12/14 series have totally different board layouts.

Problem is... It does not quite match the N12NEM either. It has a common out, noted as pin 7. The pins also appear to be shifted slightly from the NEM decoder.

I would like to resurrect this if possible. It's small and can fit in a lot of areas. Any ideas?

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[peteski]

Just looking at the components and traces, I can identify the following pins on the second photo. Shown in sequential order.

One marked "7"  - you think it is positive common "blue" pad
Square pad - motor output
Pad - other motor output
Pad - track power
Pad - track power
Pad - unknown - likely function output (headlight?)
Pad - unknown - likely function output (other headligth?)

Have fun!

[daniel_leavitt2000]

Any idea what side the right rail or motor wires are?

[peteski]

Any idea what side the right rail or motor wires are?

No, no way to tell that from the circuit.  Actually, if you skip pin 7 (blue wire), then it becomes a standard 6-pin connector.  The square shaped pad is pin 1.

So here is the pinout:

Of course since you have pin 7, the common positive from the headlights and other functions will go to that pin (not left rail pin 4).

Oh, the pads marked 3 and 4 are likely outputs for additional functions.  They appear to have zero ohm resistors (shunts) installed on-board, so you could unsolder those and replace them with appropriate resistors to eliminate having resistor off-board.

[daniel_leavitt2000]

No, no way to tell that from the circuit.  Actually, if you skip pin 7 (blue wire), then it becomes a standard 6-pin connector.  The square shaped pad is pin 1.

So here is the pinout:

Of course since you have pin 7, the common positive from the headlights and other functions will go to that pin (not left rail pin 4).

Oh, the pads marked 3 and 4 are likely outputs for additional functions.  They appear to have zero ohm resistors (shunts) installed on-board, so you could unsolder those and replace them with appropriate resistors to eliminate having resistor off-board.

Following that logic, if I replace the "0" resistors on pins 5 and 6 with "102" resistors, I should be able to run LEDs without off-board resistors, correct?

[peteski]

Following that logic, if I replace the "0" resistors on pins 5 and 6 with "102" resistors, I should be able to run LEDs without off-board resistors, correct?

You got it Daniel!