Hi!
Having a minor brain fog this morning - please humor me................
Fixin to install DCC boards in several HO P2K GPs (Limited Edition). The P2K instructions say bulbs must be replaced, calling for "12v, 50 milliamps".
I have several new Model Power # 381 bulbs - that are described as "12-16 volts, 0.03 amps". Will these work - and last - and shine brightly?
If not, what do you recommend?
Thank you!
ENJOY !
Mobilman44
Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central
Mobilman,
I'm not an electrician and I don't play one on TV, but if I read your message correctly, the loco light board is putting out 12 volts and 50 miiliamps, but the bulbs are only rated for 30 milliamps. I think the bulbs will burn out, fairly quickly, if not in the first flash.
Like you, I would want to use parts I have on hand, but you could put in LEDs and 1K resistors as an alternate.
Have fun!
Emman
I have learned a valuable lesson when I put bulbs (14v) in a super detailed Atlas RS1 and the very first show smelled that burning plastic and seeing that finely detailed, painted, weathered, and customized to pictures of the prototype shell bubble up. Since then I have switched to LEDs and 1K resistors in all my decoder swaps. If these are diesels then a sunny white LED would be great. On DCC the bulbs get hotter because they are getting full 12 to 14 volts. On DC the voltage varies and hardly gets to 12 volts and remains on the track. I strongly recommend LEDs instead of bulbs. 3 millimeter is an average size for most HO locos. Well worth the money and time.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
A 12 volt 30 miliamp bulb will be fine on a 50 miliamp circuit. As noted I'd switch over to LED's. They will last the life of the loco and run much cooler.
Springfield PA
mobilman44,
As an alternative to LEDs, why not just buy some 12v, 50ma. incandescent bulbs from Miniatronics?
I use Miniatronics bulbs in a lot of my engines. They are relatively inexpensive and last forever.
OK, maybe not forever, but a long, long time.
Rich
Alton Junction
A 12-16 Volt 30 milliamp bulb will work just fine on 12 Volts -- in fact, they will last much longer because they won't get as hot, but they will be slightly dimmer than a 12 Volt bulb. And they will not immediately burn out as one poster wrote just because they are only 30 ma instead of the recommended 50 ma.
Less is always good - many decoders can only handle 30ma on the function outputs. I still say the best way is golden-white LEDs and a 1K resistor in each, you'll never have to worry about one burning out or even worse the heat melting the shell.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thanks all!
Who is a good source for the LEDs and resistors (other than radio shack)?
Its a shame with all this high tech stuff that "they" can't produce a decoder/board that will handle existing bulbs - and/or the loco mfgs start putting out LEDs or "whatever" that will work with existing decoders.
mobilman44 Thanks all! Who is a good source for the LEDs and resistors (other than radio shack)? Its a shame with all this high tech stuff that "they" can't produce a decoder/board that will handle existing bulbs - and/or the loco mfgs start putting out LEDs or "whatever" that will work with existing decoders.
Miniatronics
They do - the Digitrax DH165L0 plugs in to any of the P2K locos that has the wires goign to a small board which is plugged in to a slightly larger board with a bunch of diodes on it. The diode board is removed and the DH165L0 plugs right in and works with the stock bulbs (except some GP38's with extra bulbs to light the number boards - those apparantly were connected across the motor terminals and cause problems)
However I prefer the TCS decoders for better motor control and while they have one that drops right in those P2K locos it doesn;t include the resistors to use the stock bulbs. So I remove all that stuff and wire in a T1, it's cheaper anyway.
Mianiatroncs Yelo-Glo LEDs are great for first generation lights, they give off a slightly yellowish glow. And unlike some the LED body is clear, only a speck of yellow/orange inside it so when the LED is visible through the headlight lens there's not a big yellow blob, just the little speck - light a light bulb. They come with resistors but neither ones is correct for DCC. If you are only doing a few, you cna get the 1K resistors at radio shack. They're a lot more expensive than Mouser bt for just a few, adding in the shippign costs will make RS cheaper. If you need to do 50 locos and need 100 or more resistors, then ordering from Mouser makes sense, the resistors themselves are like 1 or 2 cents a piece. Miniatronics LEDs aren;t cheap, but you cna pick them up most anywhere - one of the things I actualyl buy at my LHS because they always stock them. There are cheaper sources of eBay but so far I've not tried any because even if 100 LEDs for $5 is really cheap, if they are not a nice color then it's $5 wasted - I know the Miniatronics ones are the color I like. For Proto Geeps, the 3mm size works great - a little filing of the flange at the base of the LED and they drop right in the pocket in the weight where the bulb was, so it points directly into the light pipe in the shell. Once again I have failed to take photos while doign something, but this is what I did to my last GP7, I just filed the flange flat on 2 sides and the LED settled right in where it needed to be.
I usually use the miniatronics sunny white but get the resistors from Radio Shack. The resistors in the miniatronics LED pack are too low a value for decoders. Or you can pick up these from Train Tech. http://www.traintekllc.com/LEDs/products/71/ They sell 2 LEDs with 1K 1/4 watt resistors for $2.95.
http://www.richmondcontrols.com/ is another good source, he even has prewired sufsce mount LEDs. All his LEDs come with a resistor whos value you can choose..
If, once you've tried some LEDs and want to buy a lot more, you should use one of the Hong Kong e-bay sellers. They're veery cheap in bulk, I bought 100 sunny white 3mm for $12, reasonable postage and got them in less than 10 days.
Jay
C-415 Build: https://imageshack.com/a/tShC/1
Other builds: https://imageshack.com/my/albums
modelmaker51 If, once you've tried some LEDs and want to buy a lot more, you should use one of the Hong Kong e-bay sellers. They're veery cheap in bulk, I bought 100 sunny white 3mm for $12, reasonable postage and got them in less than 10 days.
I use Miniatronics exclusively.
I have been very disappointed with buying cheap LEDs in bulk on line. They are nowhere near as bright as Miniatronics. Not only sunny white, but also the red/green bi-color and the individually colored LEDs.
Another place to check for LEDs at a reasonable price are Christmas light sets. Write up here (not by me): http://web.me.com/unionpacific/The_Roundhouse/LED_Headlights.html#grid
Have to add resistors, but not a big deal. Just make sure the set you get is sunny white or golden white. The set I got is a bit bluish, but coloring the LED with a Sharpie makes it closer to the right color.
The P2K GP9s I have are older ones, so I took everything out and hard-wired. I used Minatronics LEDs on these, before I got a LED light set.
I have some P2K GP30s I put 14v bulbs in, headlights are fairly dim. Was felling lazy, and should go back and put LEDs in.
Mike WSOR engineer | HO scale since 1988 | Visit our club www.WCGandyDancers.com
Thought I would give you all a follow up on this posting..................
I selected 2 ATSF P2K GP7s and 2 GP9s to make up a consist. From Toy Train Heaven, I got a bunch of Miniatronics 12v 50ma bulbs, and NCE P2KSR decoders.
This was my most complicated (to me) DCC installation to date, and I decided to work it "mass production" with the four units. As the locos were all "new in the box/display cabinet" and that made it a bit easier.
First I "lubed and tuned" the drive train and made sure all those infamous defective geared wheelsets were replaced. Then I pulled the light boards and old bulbs, installed new bulbs, and installed the decoders. At this stage I thought it wise to test on the layout, and all four actually worked as they should!!!
Back at the work bench, I put a strip of electrical tape under the boards, and a narrow strip over them to hold them in place for installation of the shells. Then, I installed KD whisker couplers.
I reviewed the packages of detail parts (i.e. window boxes, etc.) and decided the locos were just fine for my '50s era layout. Then, all four made the trip back to the layout, and a final test before dialing in loco I.D. numbers and consisting.
Even without sound, the four together look impressive, and can pull anything I can put together - even up the two percent grade from the lower level - with ease.
Well, as I slowly progress through stages of increasing difficulty with decoder installation, my next attempt will be a detailed Stewart ATSF F7 ABBA consist - wherein all units are powered with the Kato motors and need to be hard wired. Funny thing, six months ago doing that was scary, now it seems fairly easy.
Thanks again to all that have given to my DCC education - helping to prove that 67 year old dogs CAN learn new tricks!
Thanks for the update.
Sorry for late reply, but here are the two methods side-by-each.
Left side, 14v bulb. Right side, LED.
And with most of the room lights off.