What light bulbs do I need for DCC conversions?

[mobilman44]

Hi,

I'm "fixin" to start ordering decoders for some of my locos and will start with the Stewarts (F & FT) and P2Ks (GPs, PAs, SWs, Es) - all representing 1st generation diesels. 

It is my understanding that some of these conversions require replacement of the lights (due to low voltage), or the installation of a capacitor.  My preference is to replace the bulbs.

Sooo, my question is, what specific bulbs are preferred for replacements?  

Thanks,

Mobilman44

[MisterBeasley]

I have been putting "Yellow-glow" or "Golden-white" LEDs in my engines.  You will also need a 1K (1000 ohm) resistor in series with each LED.

LEDs have several advantages over traditional incandescent bulbs.  They are very bright, and the light is very directional, like a headlight beam.  They use very little power, which saves you precious amperage against your DCC system's limit.  They give off almost no heat, so there's no danger of melting you locomotive's plastic shell.  Finally, they will probably outlive your grandchildren, so you're not going to have a never-ending maintenance task to keep your headlights burning.

[Stevert]

Interesting question!  I guess the answer is, "It depends."

  I don't have any Stewarts, so I won't comment on them.  But my P2K collection contains a few GP's of various vintages and three SW's.  I also have a pair of older P1K F3's (which use a variation of the P2K drive).

  I have a GP30 and a two GP9's with Digitrax DH163L0's.  These are a plug conversion that use the original bulbs, so they needed nothing.

  Likewise, the SW's all have TTX-SW12's, which are board replacement decoders.  Again, the decoder allows for the original bulbs to be  retained (especially handy since the cab bulbs are a pain to get to).

  My two GP18's are older, non-DCC ready models, so they needed to be hard-wired.  One has a high short hood, so removing the upper weight gave me room for a DH163D.  The other, with a low short hood, required a DZ143.  But again, I used the original bulbs with appropriate resistors.  Unfortunately, I didn't record the value I used, and they're not handy for me to pop the shells and check.

  Finally, in the P1K F3's I used DH123D's with the original light boards.  The traces were cut as necessary, allowing use of the (surprise!) original bulb/resistor combination.  They're "over-resistored" from the factory to give a nice, yellowish glow.

  So in my case, the specific bulbs that are preferred are whatever the loco came with.  After all, if it ain't broke, why fix it?

Steve        

[wjstix]

It would depend on whether you were doing a "plug and play" installation, plugging a decoder into a receptacle in the lightboard, or a "drop-in" or "hardwire" installation where you're replacing the lightboard with a decoder. In the latter case, it will depend on what the decoder is set up for. On some newer ones you can adjust the amt of output for the bulbs to allow for use with LED's or 1.5v ones. Otherwise on the older style ones I just use 12 or 14V bulbs.

[C&O Fan]

If you use a QSI revolution  decoder YOU HAVE TO use either LEDs or 1.5 volt bulbs

They are not set up to use 12-16 volt bulbs

 

A disadvantage in my opinion

[jbinkley60]

mobilman44

Hi,

I'm "fixin" to start ordering decoders for some of my locos and will start with the Stewarts (F & FT) and P2Ks (GPs, PAs, SWs, Es) - all representing 1st generation diesels. 

It is my understanding that some of these conversions require replacement of the lights (due to low voltage), or the installation of a capacitor.  My preference is to replace the bulbs.

Sooo, my question is, what specific bulbs are preferred for replacements?  

Thanks,

Mobilman44

I've used all Digitrax 165 decodes (except for a few 163s) and I've never changed a bulb yet on any locomotive due to voltage.  The entire 165 series and 163L0 series have current limiting built in to avoid bulb swaps.  I did recently change to Minitronics Yeloglo White in an old Kato C44-9W because the stock LEDs were yellow. The Yeloglo LEDs are a nice warm white.

 

[rrinker]

 My Stewrat F7 and FTs have LEDs in the amready, with a plug-in decoder there's no need to change anythign except that Stewart lieks to use yellow LEDs. Not Yelo-Glow liek the Miniatronics ones, no, these things are YELLOW like a stoplight. I've repalced the ones in my AS16 and DS4-4-1000 with the Miniatronics Yelo-Glo, and changed nothing else, just plugged in the decoder. On my P2K's I take out the light bulbs and add Yelo-Glow LEDs plus a 1K resistor on each.

 There's a huge advantage to usign LEDs or, if you ,must, 1.5V bulbs. 12-16V bulbs get HOT and can melt the palstic. It's no big deal when runnign on DC because you often aren;t runnign at full throttle, so the bulb gets maybe half the top voltage most of the time. But on DCC, when you turn on the lights, they get full voltage the entire tiem they are on. Save your shell, use 1.5V bulbs and resitros or LEDs with resistors. LEDs generate absolutely no heat, and will last longer than your grandchildren's lifetime (even if you don't have any yet) unless you connect them to a power source with no current limiting resistor.

                                       --Randy