OK here goes... I have two UP E8's that I am installing NCE D13SRJ decoders into. My ? is I have removed all the factory electronics and am hard wiring the harness. Is there a way to reuse the factory bulbs for the headlight and marslight. I don't know the voltage or currant rating of the bulbs.Also the MARS bulb has three wires 2 red and one white. Can the exsisting PCB be used at all? I don't want to fry anything. Thanks for the input.
rrgeorge
You can use the existing PCB, but the MARS light effect generated by the decoder is much better than the dual filament bulb that the factory board uses. I forget the exact values of the P2K bulbs, I think they are 3V 30ma. but don't assume that. You can also switch to LEDs, using a 1K resistor on each LED. The NCE function effects work well with LEDs.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
When I did my E9 recently I took them all out. I found that the 3 lead bulb really needed the circuitry of the OEM board. As I recall their bulbs are 1.5V.
I used bulbs to go back in vs LEDs as I like their glow in that generation of locos. Some decoder mfgs have settings for LED vs bulbs for lighting effects like MARS. So, if NCE has that setting LEDs might behave great for a MARS. There are also yellow glow LEDS that look very much like an incadescant bulb. The biggest issue with bulbs is to make sure they don't get too hot and melt something or are overdriven with too much voltage.
Yes, you need to use the proper type of LED - generic 'white' ones are too bluish, and look more like flourescent lights. Ones often called 'sunny white' are a brighter white, more like what you would find in a modern locomotive. 'Yelo glow' or 'Golden White' are more correct for older first generation diesels - these are the ones I use for my 50's era diesels. LEDs should last longer than your grandkids lifetime, and generate essentially no heat so there is never a problem with melting the shell.
TCS decoders have the most customizeable settings to make the effects work with LEDs - generally they work well with no adjustment, depending on which effect you are using. NCE doesn;t have much adjustment but they do work well for most effects using LEDs. Digitrax effects seem to only work well with incandescent bulbs. The issue is with how the 'dim' part of an effect is handled. Incadescent bulbs take a while to completely stop glowing, LEDs are instant. TCS and NCE decoders do a great job handling this difference.
Thanks Randy, I need to read the NCE manual as to the proper function wire to use for the Mars light. I am going to run these back to back so I don't need a Rear light , yellow or the green or violet . Back to the books.
RRGeorge
You can use any of those three, which one you use just changes which CV you change to set for the Mars effect.
I, too, want to put a DZ123 in a '90s P2k E8. I want to leave the old dual filament bulb and light board in. The instructions from Dighitrax are not clear but they say that (somehow) the board can be used for the Mars.. How do I wire the existing light board for the Mars (I will use the DCC for the headlight that is always on.
Do you have instructions to do this?
You have to solder a wire to the otherwise vacant pin on the 8 pin plug, on the E units this pin is wired to the Mars light circuit. That's the 'easy' way, replacing the bulb does get a much superior result.
All of the various DCC installer web sites that I have looked at and the various decoder manufacturers recommend that the P2K bulbs be removed when installing a decoder in a locomotive with the mars light.
rrinker You can use any of those three, which one you use just changes which CV you change to set for the Mars effect. --Randy
You would use functions 3 or 4 with that decoder, (the green or purple & blue wires).
Randy, your statement is not correct or I'm missing your meaning. You choose the function number (map to 3 or 4), then set your CVs for the desired effect, (Mars). It's explained in the D13's instructtions on page 3.
You can use the light bulbs with the model's light board if it has an 8-pin socket. I have one wired that way, it works quite well. On the NCE board you set the CV for on/off and the P2K board handles the Mars effect.
I've also done one with LEDs, (with 1k ohm resistors), which also works well using only the D13, although it is brighter.
The lightbulbs in the E units are 3.0 volts, so you would have to figure out the resistance needed to run off the NCE board's 12v outputs. The Mars bulb would have to be wired to the Blue, green and purple wires and the CVs set for alternating ditch lights and then you would also have to set the flash rate CVs. A better solution would be to use a regular bulb with appropriate resistance and use the Mars light CV settings.
The best solution is to use Golden White LEDs with the 1k ohm resistors and the NCE D13. The Golden White LEDs are available from Richmond Controls and Litchfield Station amoungst others.
Jay
C-415 Build: https://imageshack.com/a/tShC/1
Other builds: https://imageshack.com/my/albums
Sorry, I have been away for awhile. I have installed SMD yeloglow LED's in one of the engines so far ,but have not been able to go beyond that. The testing and CV programing is going to have to wait for me to get back to modeling. Life takes over some times, such as a 100'+ tree about to fall on my car port. So for now, thanks to all that have posted reply's .I know that we will succeed. RRGeorge
I said the same thing. If you connect the Mars light to function 3, then there's a CV you chage so that the fucntion 3 wire has the Mars effect. If you use the function 4 wire instead, then it's a different CV to set.
To use the built in circuit, when plugging in an 8 pin decoder, you have to connect an extra wire, either the green or purple, to the pin on the 8 pin that usually has no wire attached. That function is then used as a simple on/off. no effects programmed, wich turns on or off the factory circuit. Not as good as the decoder-generated Mars effect but it will work.
I'm back , Thank you all for the great help and hints. the project is half done 1 down and 1 to go.I ended up installing smd's and after sitting down and writing all the CV's... SUCCESS... The NCE effect is very impressive. I did find that even with "Yelo glow" smd's they still had a blueish tint to the color. Solved that with a thin " one pass " Sharpie orange marker , now they look more like light bulbs. thank's again for everyones help.
George