Flickering head light on Digitrax DN167K0E

[craigolio1]

Hey all. I just installed a DN167K0E in a Kato FP7. The headlight has a very rapid flicker when it’s on, and when you turn it off, it has a very dull flicker. I did swap out the LED with a more appropriate coloured one as the original came with was very yellow. But that’s the only modification I’ve done to the decoder. During the install, I wrapped the contact strips in Kapton tape to isolate the motor leads as is best practice. So I genuinely believe there are no shorts. The locomotive runs properly and forward and reverse. Just curious if anybody has any ideas about why the LED would be flickering? I put a ticket into digit track to discuss it with them as well. I also tested it with the original LED and don’t remember seeing a flicker, but I did so very quickly just prove it worked before removing the LED and installing the new one.

Thanks, Craig.

[peteski]

I ran into this some time ago and it took me a while to figure it out. Turn off Digitrax transponding (it is on by default on 7th generation decoders like 167).  I don't remember what CV or what bit. The white LEDs are very efficient and they show the flicker.

[MK]

Peteski is correct.  Just set CV61=0.  Ran into the same problem myself and that fixed the problem.  I found the solution on the Digitrax Groups.IO.

[craigolio1]

I ran into this some time ago and it took me a while to figure it out. Turn off Digitrax transponding (it is on by default on 7th generation decoders like 167).  I don't remember what CV or what bit. The white LEDs are very efficient and they show the flicker.

I’ll try that!!  Thanks.

Craig.

[peteski]

I suspect that they use the front headlight LED as an electrical load for transponding. Maybe in a way similar to how the motor is used for generating ack. pulses during service mode programming. Maybe not the best idea  . . .

[Dwight in Toronto]

Damn, time and again, TRW just keeps comin’ on through for folks!
Great stuff guys.

[learmoia]

I'll give it a try as well.. I noticed it on some of my installs also..

[MK]

Damn, time and again, TRW just keeps comin’ on through for folks!
Great stuff guys.

TRW, Satisfaction guaranteed or your money cheerfully refunded!

[craigolio1]

A reply from Digitrax support confirmed this is the correct fix.

Craig

[peteski]

A reply from Digitrax support confirmed this is the correct fix.

Craig

Well, not surprising.  I wonder how modelers who use Digitrax transporting and have white LED headlight deal with this?  Personally I have never visited a layout which uses that feature, or seen it mentioned here. Maybe some big clubs do. Someone must be using it. 

[John]

Transponding is a good idea especially if you want to automate things.  There was a guy that had a Japanese themed layout online some years back that used it .. I can't remember the site now .. JMRI will allow you to automate a lot of stuff based on block detectors, so I've never used it ..  Hans Tanner has also done some work using GPS for train locationss

[John]

I just had this happen today on a new DN147A0 that I was installing into an Atlas GP38 (MMID) .. it looked like the setting was on by default out of the bag ..  fortunately the Railwire knowledge in this thread made it an easy fix

[peteski]

Yes, as I mentioned in my earlier post it is on by default on 7th generation decoders like 167.

[John]

Yes, as I mentioned in my earlier post it is on by default on 7th generation decoders like 167.

Yes .  that's where I got the idea to check