I installed a Digitrax SDH164D on a Proto 1000 RDC-1. I turned the LED off with the F0 key on my throttle. When I move the RDC forward or backwards the LED turns back on dimly and flickers. How can I solve this issue?
Not to use a decoder that recommends NOT using LEDs with them.
David B
p.s. Check that you have Transponding turned off. Google to find out which cv that is…
Where did you find such a recommendation?
Quote " We do not recommend using LEDs with FX effects because they don’t give realistic lighting effects."
http://ikm.digitrax.com/questions/1324/Ditch+Lights+with+FX+Decoders+
They are correct, I have not been able to get LED ditch lights working to my satisfaction and have ordered a replacement decoder (ESU) and will use the Digitrax somewhere else, where lighting is not so important. I am a big fan of Digitrax equipment, but this is my last decoder from them.
My first two decoders were Digitrax. Besides a Soundbug I got to play around with, they were my last two Digitrax decoders. Since I got back in the swing of things, those two are now sitting in a drawer, replaced by TCS. They REALLY need to fix the BEMF before I buy another Digitrax decoder. It wouldn;t be hard to make LEDs work, either, but that would require another code change and probably a CV like TCS has to adjust it so it works proeprly with both incandescent bulbs and LEDs.
–Randy
Thanks for providing that info.
I have two comments.
First, LEDs apparently will work, they just “don’t give realistic lighting effects.” So, I am not so sure that David’s comment actually addressed the OP’s problem.
Second, if LEDs don’t perform as well as incandescent bubs, why doesn’t Digitrax put that statement in the Owner’s Manual that is shipped with the decoder?
This whole issue amazes me.
Rich
Indeed, they LED’s work fine for headlamps and simple on/off functions with Digitrax decoders. The response from David has more than a bit of history and prior experience wrapped up in it.
Who knows. What amazes me more is that this is not a bigger issue and that complaints and demand from the market have not forced a design change?
Solution to the OP’s problem I believe would be to turn Transponding off. I vaguely remember seeing somewhere that transponding can make an LED headlight flicker, since the transponding pulse is generated by pulsing F0 (like the motor is pulsed when programming). An Incandescent bulb wouldn;t light up with the short duration pulses, but LEDs do.
On/off lights work fine as LEDs with Digitrax decoders - it’s anythign that requires them to dim or blink off where there is a problem. LEDs don;t really ‘dim’. The function outputs usually use PWM similar to the motor drive to reduce the average ‘on’ time to make the lights dim. Problem is, LEDs respond almost instantaneously, unlike an incandescent bulb where the filament glows for a time after current is removed. LEDs need much less ‘on’ time to appear dim, compared to an incandescent. The decoders that do work well with LEDs, like TCS, sometimes have a CV to adjust this. I’m guessing with TCS that the CV controls the average ‘on’ time, since you use lower values for LEDs and higher values for incandescent. Digitrax ha sno adjustment, just a fixed value, which works really great with incadescent bulbs - the effects really are good. But not so much with LEDs.
–Randy
I am not sure about Digitrax, but some decoders depending on CV29 and other CVs have fof, for, etc lighting capabilities. QSI does this. The flickering, assuming you don’t have any FX activated could be due to bad connections, etc. You may want to try a reset?
Richard
I have learned about the op’s intentions over the past year and he wants to have transponding working on his layout.
With transponding, Digitrax sends out a small signal with the F0F output (white wire). With a filament type bulb, this signal has no side-effect, however with LEDs it causes them to flicker.
Hence Digitrax suggests that you do NOT use LEDs with their decoders when you intend to use transponding. Hence why I commented on the OP’s poor choice of lighting source…got it?
David B
David,
I got it ! LOL
As I said in an earlier message, though, I am surprised that this is not mentioned in the specific product sheet for that decoder.
Sounds like TCS is winning the Decoder War, hands down.
Rich
I have no LED issues with the Digitrax DH165A0 only the SDH164D. I will still convert to TCS decoders.
Transponding is probably off in the in the DH165A0. It normally is by default, but it may have gotten turned on in the SDH.
You don;t actually need transponding to automate operations. The Train Tracker feature in RR&Co is quite sophisticated, and you can do similar in JMRI, it just takes some scripting.
–Randy