Mark R. Congratulations ! You got more patience than me when it comes to wanting to decipher some of those factory boards. Mark.
Congratulations ! You got more patience than me when it comes to wanting to decipher some of those factory boards.
Mark.
There is a bit of history to this project that backed me into somewhat of a corner.
When I bought the two PAs, I had the two D!3SRP decoders on hand, so I thought, why not just plug them in, no problemo. But then I realized that the pins were bent on one of the plugs and a wire was broken on the other decoder. So, I sent them back to NCE, waited a month, and then got back new replacement decoders. So, at that point, I couldn't bear to cut off the plugs.
In retrospect, it was no big deal, but I got stumped when the LED wouldn't light. So, if nothing else, it was a learning process. If I had it to do over, I might well have approached it differently, hard wiring over the plug in approach. But in the end, it all worked out.
Rich
Alton Junction
Seriously For me, step 1 in any DCC install is to rip all the factory bulbs and boards out and chuck em. ditto with the factory wiring, since its usually clor coded wrong!
Karl
NCE über alles!
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
mlehman Excellent! Sounds like the LED Mars light effect works for you?
Excellent!
Sounds like the LED Mars light effect works for you?
Yeah, the Mars light effect is nice, a lot better than the incandescent. I should take a short video.
My Golden Whites arrive on Monday.
Mike Lehman
Urbana, IL
Ooh, ooh, ooh. Got the Mars light rotating. CV122=9.
Gonna wrap this project up.
Life is good !
Got both LEDs working this morning.
I believe, as Randy suggested, that a diode or resistor on the DC board, limited power to the headlight LED. So with the resistored leg on the headlight tab and the non-resistored leg one one of the Mars tabs, I got the LED headlight to work using F0.
As for the Mars light, the Output 3 and Common connections are on the DCC decoder board. I got the Mars LED to light using F1.
Next up, program the CVs to create the Mars light effect.
rrinker Very likely there is an additional diode and/or resistor in the lamp circuit on the DC board so that the stock bulb could be used. I gave up trying to trace those messes a long time ago, just hard wire the decoder, problem solved, because you will KNOW the decoder wires are connecting to the correct LED leads. --Randy
Very likely there is an additional diode and/or resistor in the lamp circuit on the DC board so that the stock bulb could be used. I gave up trying to trace those messes a long time ago, just hard wire the decoder, problem solved, because you will KNOW the decoder wires are connecting to the correct LED leads.
--Randy
Before I give up on the D13SRP, I will give it one more try in the morning. Apparently, I did find Output 1 on the DC board because I got that LED to light. Output 3 and Output 4 are on the DCC decoder board, and those can be used for the Mars light.
If that fails, then I will just use the two D13SR decoders that I have on hand, so I don't have to cut off the plugs on the D13SRP decoders.
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
richhotrain Mark R. Just my two cents .... but in the time you've spent trying to diagnose that factory board (and still are), you could have by-passed the board, wired everything direct and be playing trains by now .... Mark. Or, putting it more bluntly, I should have listened to you in the first place. Rich
Mark R. Just my two cents .... but in the time you've spent trying to diagnose that factory board (and still are), you could have by-passed the board, wired everything direct and be playing trains by now .... Mark.
Just my two cents .... but in the time you've spent trying to diagnose that factory board (and still are), you could have by-passed the board, wired everything direct and be playing trains by now ....
Or, putting it more bluntly, I should have listened to you in the first place.
Just sayin' ....
Just did the other PA. Same result. The LED won't light on the two headlight tabs on the DC board.
But one LED leg on the headlight tab and the other LED leg on any one of the Mars light tabs, the LED lights in forward.
OK, this is weird, at least to me.
I started fooling with the LED on the DC board tabs.
I touched the short leg with the resistor to one of the headlamp tabs and the long leg to one of the Mars light tabs. It lit. In fact, it lit when I touched the long leg to any one of the three Mars light tabs.
What is going on here?
P.S. With the motor in reverse, the headlight did not light, as expected.
richhotrainEdit Note: I just had a thought. Would it make any difference if I reversed the decoder plug? It is inserted to run forward, unless the motor wires are reversed.
Gotta have the correct directional bit in there, too, so you add a 1 to make it come on in Forward in CV 120 IIRC.
Here's where the wires go on mine with that decoder...
The decoder plugs into the 8-pin.
The blue wire to the headlamp attaches to the factory board at the very right rear tab.
The white wire to the headlamp attaches to the factory board at the third tab in from the right rear.
The green wire for the Mars lamp runs from the J1 spot on the 8-pin plug to the Output 3 on the decoder. The J1 spot shows not being used on page 2 diagram of the pin-outs for the D13SRP, so I added that. I also added a wire between the LED and the common located between the Output 3 and Output 4 because it was easy to access there.
I suspect I came across this hack on the internet, because it's way more engineering than I can usually come up with.
I also may have swapped in resistors tgo my taste at the back of the factory board, not certain. I like things a little dimmer, but suspect the factory one are sufficient for LED protection.
richhotrain So far, the only light that I am testing is the headlight, not the Mars light. I put the 2 legs of the LED into the same tabs where the headlight incandescent bulb was located. The headlight is controlled by the headlight button (F0) on my NCE Pro Cab. Rich Edit Note: I just had a thought. Would it make any difference if I reversed the decoder plug? It is inserted to run forward, unless the motor wires are reversed.
So far, the only light that I am testing is the headlight, not the Mars light.
I put the 2 legs of the LED into the same tabs where the headlight incandescent bulb was located.
The headlight is controlled by the headlight button (F0) on my NCE Pro Cab.
Edit Note: I just had a thought. Would it make any difference if I reversed the decoder plug? It is inserted to run forward, unless the motor wires are reversed.
If you are looking at the engine from the rear, pin 1 on the socket is on the front left of the eight pins. Pin one on your decoder plug corresponds to the orange wire.
Just for giggles, re-install the bulb and see if it works (provided the bulb is good).
No, you only have 8 pins, and only 7 have wires. 2 for the rail pickups, 2 for the motor, 1 for the blue functionc ommon, and the white front light and yellow rear. There is no power feed to the circuit for the Mars light circuit - though this is what I mentioned about the modification to connect an extra function wire to the 8th pin on the 8 pin connector, it then allows that function to power the Mars circuit. But it won't give any constant power to any pads, it will merely supply the on-board flasher circuit and thus blink the two outputs for the Mars bulb.
Yeah, tried that but nothing.
Is there some way to test the tabs on the DC board with a meter?
When you plug in the D13SRP onto the DC board, shouldn't it pick up the lighting circuitry?
Don't forget, LEDs - unlike bulbs - are polarity sensitive. If you have it installed backwards, it won't hurt it, but it won't light either. Try reversing your connections.
Without the modification to the 8 pin plug I mentioned, the only tabs on the factory board that would have power would be the ones for the main headlight, i using a plug-in decoder.
Mark, the Golden White LEDs that I ordered won't arrive until Monday.
So, on a temporary basis, just to test the lighting, I am using some 5mm High-Brightness White LEDs from Radio Shack with 750 ohm resistors.
They are pretty bright when I test them with a 9 volt battery and just as bright when I contact them on the solder points of the decoder.
It makes me wonder if when I plug in that D13SRP whether it is looking for the same tabs as the DC setup with the incandescents. It just seems like there is no power on those two tabs on the DC circuit board.
Most likely there is an onboard resistor for the bulb. Is the LED quite bright or rather dim for what you want ?
And, yes .... this is another reason I scrap the factory boards. They come up with some real dandies some times. Getting your mars light to run off that board using an LED will be a real treat as well.
I have encountered my first problem with the lights, and maybe this is why some advise bypassing the DC board and hardwire the decoder.
I installed the D13SRP decoder by plugging the 8-pin plug into the connector on the DC board.
I placed an LED (with resistor) on the DC circuit board tabs where the incandescent bulb was located for the headlight. I set the loco running forward with the headlight button activated but nothing, no light.
When I place the LED legs on the solder points where the plug wires are connected to the decoder, I get the lights to come on.
Any ideas, thoughts, suggestions?
I left the DC boards in place, removed the two incandescent bulbs and wiring in place, and installed the D13SRP decoders. All went well.
Next up, the installation of the LED lighting which I ordered, and it is on the way.
I am going to cautiously install the D13SRP decoders today and then wait for the LEDs to arrive before installing the lighting.
I will report back.
On ones I did, I left the board in place, but I pulled all the black plastic clips and removed the wires and connected them directly to the decoder. The factory board is 100% bypassed, but if I would ever need to make it a pure DC loco again I could just cut the wires and reconnect them to the factory board with the clips.
You may find some install instructions that have you add one of the extra function wires, purple or green, to the one spot on the 8 pin plug that normally is a no connection - the blank spot is what makes it safe to plug the 8 pin connector in backwards - nothing fried, but it won;t run right either. Life Like connected that pin of the 8 pin socket on the factory board to the mars light circuit on the board - so if you add one of the extra function wires you can retain the stock setup and trigger the Mars light. But - I still say most any decoder does a better job of simulating the Mars light than the stock two filament bulb and circuit.