I have an older Atlas Dash 8-40BW non sound that I removed the Old Dual mode decoder and replaced it with a Soundtraxx AT 1000 FDL (modern) sound decoder. The installation is done except for the lights. The original lights look like bulbs but only light when I test them with a 9 volt battery not a 1.5 battery.
Like I said above, I think these are bulbs not led's so the question is Did Atlas use higher voltage bulbs on their older engines and if so can I use the same connection points as for leds on the Tsunami? Do I need resisters also?
I searched the Atlas website with no luck.
Thanks for the help,
Marty C
All my SoundTraxx decoders deliver 12 VDC from a DCC system. A far as I know, older HO locos used 12 to 14 VDC bulbs. I have a few older non DCC locos.
Put your voltmeter probes on the output terminals on the decoder.
I have never been able to light an LED with 1.5 volt battery. An LED requires at least 2 to maybe 3 volts. A 9 volt battery with 1k resistor works also.
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
If you physically removed one and looked at it and it is a bulb (it's pretty obvious, vs an LED), and they only work on 9V or more - then you pretty much answered your own question. I would repalce them with LEDs while you are doing all this work, so you (hopefully) will never have to replace them later. If they are indeed 12-14V bulbs, you probably don;t want to use them - they may draw too much current for the decoder function outputs, plus on DCC they will be at full brightness (running on DC< unless you drive your trains at full throttle all the time, they never get full voltage), and thus can get hot, hot enough to melt the plastic. LEDs have none of these problems AND last practically forever.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
If you insist on the bulbs, put a 22 ohm, ½ watt resistor in series with one lead. Prolongs life. Voltage surges when the decoder lights a bulb is what many times blows out a bulb. But the conversion to LED's is a good suggestion along with 1k, ¼ watt resistor.
Rich and Randy,
You are right, I have answered my own question and agree that Leds will be the best install. Thanks for the quick replies.