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    • July 16, 2020 9:23 PM EDT
    • Adam Dziuk said:

      Just a thought,

      It appears the flickering LED lights when the loco looses connection with the track.

      I'm wondering if the motor is acting as a generator as it free spins, especially if it has a flywheel, when it no longer has input voltage applied and back feeds voltage to the LED? A capacitor in the circuit may even intensify the problem. It doesn't take much voltage or amperage to momentarily light an LED. 

      Adam

       

      Interesting idea. There is no flywheel and, of course, it has worm gears but there is some momentum when it loses power. Maybe I just need to make it into a test sled when I take the cab off and try some ideas.

      Or maybe make this the next battery RC conversion on my list and go with direct lighting from the RC receiver. Hmmm....

       

    • July 16, 2020 9:09 PM EDT
    • Just a thought,

      It appears the flickering LED lights when the loco looses connection with the track.

      I'm wondering if the motor is acting as a generator as it free spins, especially if it has a flywheel, when it no longer has input voltage applied and back feeds voltage to the LED? A capacitor in the circuit may even intensify the problem. It doesn't take much voltage or amperage to momentarily light an LED.

       

      Adam

    • July 16, 2020 8:33 PM EDT
    • Jon Radder said:

      OK - Can you take that pack and connect it directly to the loco - no track?  I still suspect intermittent loss of track power may be the cause.

       

      Well, Gentlemen, your assumptions are correct. I hooked the battery pack to a Kadee wheel cleaner and ran the motor in both directions. If I held the cleaner firmly to the wheels, flicker was eliminated. If I applied intermittent pressure, the 'off' LED flickered, as shown in the video. I guess the next attempt will be the parallel capacitor. Since that will require the third disassembly, I will take time to do some other up grades. Will report back when it is finished. Thanks for your insights! 

      Regards,
      David

       

       

    • July 16, 2020 5:54 PM EDT
    • OK - Can you take that pack and connect it directly to the loco - no track?  I still suspect intermittent loss of track power may be the cause.

    • July 15, 2020 10:03 PM EDT

    • I disconnected the MRC unit and connected an 11.1 volt Li Ion battery pack directly to the track:

       

      The flicker appeared to be exactly the same (I tried slo-mo but YouTube speeded it up so I ended up with a grainy, fast video):

       

       

      I did find more specs on the diodes I added and it shows 'Reverse Current at Peak Inverse Voltage' of 10 Micro Amps. I assume that the diode is feeding that amperage back to the off side of the LED when at PIV, which is 200V for this diode. Is there enough amperage at the 4 or 5 volts of the power feed to flicker the LED?

      I have used capacitors to keep passenger car lights on but not sure how to keep an LED off.

      Still a lot to learn, I'll keep trying. Appreciate your suggestions.

      Thanks,
      David

    • July 15, 2020 9:30 PM EDT
    • Perhaps a capacitor wired in parallel with the LED will smooth out these "peaks" and solve the problem.  Use the series diode to be sure it only gets dc and is rated for more voltage than it will ever receive.  I do this for the LEDs in my streamliners to prevent them from flickering over dirty track.

    • July 15, 2020 8:43 PM EDT
    • I have no data, but I suspect it's a half-wave rectifier.  You could easily add a robust bridge rectifier to the output.  You could prove that the supply is the issue if you have a drill battery you could hook up to the loco with clip leads. I suspect on pure DC with a solid connection, you would not get the flashes. It may also be back EMF from the motor as it momentarily looses connection with the track.  You could hook up directly to your supply (not with track) and see if the problem goes away.

    • July 15, 2020 6:50 PM EDT
    • Jon Radder said:

      What is your power supply. Is it possible there may be some stray AC on the rails?  The flashing looks like it may happen when there is a slight loss of track power.

       

      Thanks for the comment. My power supply is an MRC Tech II Railmaster 2400, originally used on my HO layout, now in service on my indoor test track. Not current high tech, but has done a good job with my low amp engines. I never have the 'Pulse' switch on when running. I don't know how clean the output is. 120v input, 14 Volts DC variable output for the trains and 18.5 Volts AC output for accessories and another 15 Volt DC fixed output.

       

    • July 15, 2020 6:10 PM EDT
    • What is your power supply. Is it possible there may be some stray AC on the rails?  The flashing looks like it may happen when there is a slight loss of track power.

    • July 15, 2020 4:43 PM EDT
    • My grandson likes to disassemble computers and salvage parts. He had a couple of LEDs and wanted to know if we could use them on my railroad. We got together and put them on a Hartland Mighty Mack as marker lights on the roof. We wired them so forward was the front headlight (which we had converted to an LED) and green LED; reverse is the rear white light (LED) and red LED. Test:

      The problem is that whichever LED is supposed to be off blinks. In the video below, note that the green LED in on and the red LED is flashing (look carefully):

      When I noticed this problem, I put a Radio Shack diode (below) in series with each LED in order to block the reverse current but the 'off' LED still blinks. How do I solve the 'flashing/blinking problem?

      Diode

      Thanks,
      David

    • June 17, 2020 6:19 PM EDT
    • Jon Radder said:

      Nice. What control system are you using?  C-19 sparkie or steam?  Oh, you said servos, so live steam.  RCS Tx/rx ?

      Yes, the C-19 is live steam. It always had the Orange, so I put that back inside the tender. Found some bent pins, but all is now well and it is ready to go to a new home.

      I left my RCS TX-3 in Florida (accidentally) so the TX is a standard DX6i. Amazing it still works after all these years, but then it doesn't come out of hibernation very often. I do have a couple of RCS Cobra 24V ESCs for my electrics - one is in the little Feldbahn engine.

       

      I soldered up a cable for the micro-RX this afternoon as part of my testing of the RXs. I also printed the instructions, which turned out to be wrong - they had the 4 small sockets labelled the opposite of the cables (black/+ at the opposite end.) So I assumed the engineer knew what he was doing and tried it anyway. The instructions also pointed me to the tiny 'bind' button (it's visible near the 3 power pins in the front.) I was wondering where the bind plug would go! Very interesting, and it worked.

       

       

    • June 17, 2020 3:58 PM EDT
    • Nice. What control system are you using?  C-19 sparkie or steam?  Oh, you said servos, so live steam.  RCS Tx/rx ?

    • June 17, 2020 3:02 PM EDT
    • I have to put the receiver (RX) back in my C-19 tender, and I received 2 packages from my favorite supplier recently, so I figured you guys might like a photo.

       

       

      I've used the Orange RX before, and I think this one came out of something else, as my pal asked me if I had a use for the 'battery' thingie. Nothing special about the Spektrum except the neat pin layout. The interesting one will be the micro RX in the foreground, which is (presumably) designed for small drones, etc. It came with the cables which will have to be connected to servos - good job I have some spare extender cables. Now I have to find out how to make it "bind" to my DX6i.

      Stay tuned.

    • June 16, 2020 10:34 AM EDT
    • Derailed said:

      "Keep in mind that your DCC's track power voltage drops about 1.5 volts on the outputs in your DCC decoder."

      Is this due to a bridge rectifier inside the decoder?  1.5v is pretty close to the voltage drop across the 2x diodes in a BR.  I assume the decoder has some form of BR for accessories such as lights and smoke.  

      One of these days I will take an electronics class at the local college.  

      Its not a bridge rectifier, at least not for the motor output, its an H bridge. For lights and such it would be a rectifier circuit of some kind. Also, on the switchable outputs (lights, smoke), there is also a switching transistor in the circuit. So yes, your actual voltage output would be reduced by the forward bias voltages of these components.

    • June 16, 2020 10:16 AM EDT
    • Derailed - I'm not an electronics engineer so can't answer your question.  Someone like Greg Elmassian will need to chime in on that one.

      I install a lot of Massoth XLS DCC/DC Sound Decoders.  Massoth Technical Department informs me that the outputs on these decoders is not DC or DCC Voltage.  Instead it's pulse modulation with 25 volts (peak voltage) and smaller for lower voltage.  So, they advised me to use an RMS Multimeter in AC mode with load to measure the voltage outs from their decoders. So I don't use the RRamp to measure these decoder's outputs; I use the RRamp to measure the DCC voltage from my Command Stations to the track.....and amps.

      I'd be curious if Greg or others know whether this approach is used by other DCC Decoder manufacturers, such as ESU, Soundtraxx, etc.

      Tom

       

    • June 16, 2020 9:57 AM EDT
    • "Keep in mind that your DCC's track power voltage drops about 1.5 volts on the outputs in your DCC decoder."

      Is this due to a bridge rectifier inside the decoder?  1.5v is pretty close to the voltage drop across the 2x diodes in a BR.  I assume the decoder has some form of BR for accessories such as lights and smoke.  

      One of these days I will take an electronics class at the local college.  

    • June 15, 2020 12:58 PM EDT
    • Thank you.  I have to wait until next month as I bought a new Pustefix car for a price I couldn't pass up.  Need to replenish my Train Stipend.  ;)  

    • June 14, 2020 9:05 AM EDT
    • Derailed said:

      Not sure if this is the correct location for this question.

      I plan to buy the RRAmpmeter.  I see they now offer a version 4.   It says it handles DCC of 18-20A.  Usually I see ranges of 1-20A or up to 20A.  I am running 10A Brutus.  Does anyone have the version 4?  Will it read down below 10A?  

      Hi Derailed - You received your answer.  I do have the RRamp V.4 and find it a great tool.  Let me know if you have any questions after you start using it.  Keep in mind that your DCC's track power voltage drops about 1.5 volts on the outputs in your DCC decoder.  This is a good data point to consider when you're adjusting your DCC decoder's outputs for things such as lighting, smokers, etc.  Also, when measuring voltage outputs on your decoders, do so under "load", i.e., have the device connected to the decoder's output, e.g., light, motor, smoker, etc.

       

    • June 15, 2020 9:23 PM EDT
    • That is a big cigar.  I think I would turn green before I finished it.  Or just waste about 12".  I once had a 9" torpedo that was about 1.5" thick.  Took me 3 sittings to finish that thing off.  I know, you aren't supposed to relight a cigar but I was in Iraq and cigars weren't easy to come by.  My tolerance is more of a Robusto length.  I got my wife to switch from cigarettes to cigars so I could have a full time smoking buddy.   ;)

    • June 14, 2020 8:54 AM EDT
    • I got it solved.......got some help from a long-time ESU large scale decoder user/installer.......the Massoth Pulsed Smoker now works great with the ESU 5 XL.