Hello once again. I solved the Tsunami MU problem with the help of you guys now I have another.
I put in a Digitrax DH165A0 decoder in my newest run Atlas RS1. Everything went just fine and it runs on DC and will run as its is supposed to on dcc using address 03. But the Atlas LEDs do not light up in dc or dcc. I made sure they were wired at the ends like they are supposed to positive to neg etc. I also pulled one back off and tested it on the track with just the leads and it works fine.
Is there something I am supposed to do to make the tabs live?
Thanks again for your help. With your help DCC is winning me over.
I'm having a similar issue with a backing light, but a few things may help you
1- have you hit the "light" button (F0)?
2- did you by chance leave any diodes in place? No biggie unless they're backwards, in which case they'll do what they do and prevent any forward current
3 are you sure the LEDs are connected to the right leads? Most only take power one direction.
4. If you were able to put it to track voltage and have it work, did you break the little "V" trace at the front of the decoder for high current applications?, or at least ensure that you dont need to? I'm not sure if you have a resistor on the LED or not, just something to look into.
5. Have you tried smacking the engine?, the wiring?, the Zephyr? If so, you're frustrated. Just WALK AWAY for a bit
The obvious stuff was tried, you are right it usually is something obvious that I skipped.
There does seem to be diode or resistor in the positive wire. The digitrax instructions are very vague about the v. I guess it would help if I knew what the amps are for the Atlas LED. You think maybe it takes more juice ad I need to cut the v?
Thanks
Maybe take a 12-16v lightbulb and hook it up to the leads and see if that lights up?? If so, you know the leads are getting power OK.
It has become stranger. I took an old grain of wheat bulb that is at least 12 volts that worked fine on track leads. Wired it in and nothing on dc or dcc. The Atlas LED at one end seems to try to come on faintly on DC but nothing on DCC. I'm beginning to think I have a bad light path on the board or it is very finicky about the LED voltage. I have sent Digitrax an email. Ill see if they have any solutions.
The DH165A0 already has a current limited output for the LEDs - if there are already resistors in line they need to be removed. Out of the package, the DH165A0 is set for 15ma to the headlight outputs, perfect for LEDs. The instruction sheet included with the decoder explains all this.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
The fact that the light barely glows in DC, neans there is only about 2 volts output at the board, meanimg it's just right for an LED without a resistor. If you have an LED without a resistor try it it should lite up.
Jay
C-415 Build: https://imageshack.com/a/tShC/1
Other builds: https://imageshack.com/my/albums
try putting a 1.5VDC grain of wheat bulb on the leads. Not the track, it will just pop it. Just put the leads right on the F0 tabs if possible, -you can leave the other light hooked up. The things that are inline on the original lighting may be diodes. If they are black and have a silver band with an arrow looking thing, it's a diode, which is used to control the directional lighting and there would be one at each light. They can be left in providing the (+) and (-) wires are hooked up correct. Resistors will have several bands of colors and are tan (normally). The resistors are meant to drop the voltage for a device, so unless you have the decoder set to deliver track voltage to the lights the resistors will not allow enough voltage to light the LED.
I finally figured out this afternoon that the board does only put out enough for a small bulb or LED. The instructions are a bit vague here.There is only a couple of run on sentences about options for lighting, a notation about ma's at the tabs would have been useful.
Page 6:
The DH165A0 is configured to control the forward-headlight F0F/white lead and reverse-headlight F0R/yellow lead for directional lighting. These two headlight function leads are current regulated for LEDs or lamps, with factory setting of approx 15mA, with no resistors required. Cut the ADJ link to increase headlight current to approx 30mA- see fig 4. I dunno, seems pretty straightforward to me, F0F and F0R are factory set to 15ma for small bulbs or LEDs, no resistor required. --Randy
The DH165A0 is configured to control the forward-headlight F0F/white lead
and reverse-headlight F0R/yellow lead for directional lighting. These two headlight
function leads are current regulated for LEDs or lamps, with factory setting
of approx 15mA, with no resistors required. Cut the ADJ link to increase
headlight current to approx 30mA- see fig 4.
I dunno, seems pretty straightforward to me, F0F and F0R are factory set to 15ma for small bulbs or LEDs, no resistor required.