12v lightbulbs for genesis Sd70 series engines

[Anonymous]

Tom,

I am not familiar with Digitrax decoders, but rewired the GP38-2 completely.
I did the number boards under F1, blue and green wire on the decoder.

[tsasala]

Cor - I saw your post and it saved me after my decoder wouldn't work. I could control the headlight direction, but the engine wouldn't move. Very frustrating until I put your information together with notes on the digitrax web site. Now I know that at least with the P2K GP38-2, the number boards need to be disabled to get the decorder to work properly. Now I'm trying to figure out if I should replace the lamps or put in resistors. I haven't been able to find any concrete advice or opinions on this board. Thanks again.

-Tom

[Anonymous]

tsasala,

See my previous post,
For the p2k GP38-2, well,... could be it has to do with my attempt to keep the light out the cabin. But if I look at the shell now, I would go for resistors.
Maybe others have better experience though
Brgds
Cor

[tsasala]

I just got some 12v lamps for my P2K GP38-2 - should I put in resistors instead?

[nfmisso]

Say 15 V supply - typical DCC, 15mA 1.5V bulbs - leads to 13.5V 15mA -> 900 ohms.

For safety, start with 1K ohm resistors, one for each bulb.

[Anonymous]

If you call Athearn you'll find out the bulbs are 1.5 volt 15MA. I forgot what size resister I used but I think it was in the 600 to 800 ohm range. I like dim lights as they last longer.

[Anonymous]

Stltrains,

The (new) Genesis SD70MAC’s are DCC ready, just plug in a decoder and run.

If you’re talking about the genesis SD70M/I or SD75, use resistors as Nigel advises.

I recently put some 14V bulbs (my LHS didn’t had 12V as LL recommended) in a P2K GP38-2, but I didn’t like the way it lighted up the cabin. (far to bright )
So I toke an old credit card adjusted it to fit in the cabin and glue it under the light holder, in order to keep the light from leaking in to the cabin.
Its looked fine at start, but since the piece of credit card was very close to the bulb I wanted to make sure it didn’t melt, so left the light on for about half an hour.
Well….., guess I was lucky to be around because the piece of credit card is still ok, but the cabin shell started to melt en it looks now as if someone throw an piece of rock on the cabin from a bridge or so.

So I am going to replace the bulbs of all my P2K stuff with LED’s.

Best regards
Cor

[nfmisso]

NOT a good idea, use the stock bulbs and current limiting resistors or other method of voltage or current limiting. I like LM317 regulators.

Someone in another topic mentioned that they are 1.5V 30mA bulbs; --- 0.045 Watts. For !2V bulbs would have to be 3mA to generate the same amount of heat. Excess heat will visibly damage the shell.

[Anonymous]

what types of 12v lightbulbs will fit in the bulb holes in athearn genesis sd70 locos

digitrax specifies 12v bulbs