Author Topic: Using Stock Analog Light Board With Wired DCC Decoder?  (Read 1003 times)

0 Members and 1 Guest are viewing this topic.

MetroRedLine

  • Crew
  • *
  • Posts: 553
  • Gender: Male
  • Respect: +156
    • Union Pacific Vallealmar Subdivision (Facebook Page)
Using Stock Analog Light Board With Wired DCC Decoder?
« on: September 01, 2019, 06:08:50 AM »
0
For my Labor Day Weekend project, I'm planning to do my first real wired decoder install (I installed a wired decoder into a Tomix Thomas the Tank Engine last year, but it was too easy to be considered a *real* wired install ). The subject is a Digitrax DZ126 into Life-Like 2nd Generation GP38-2, released in the mid-2000s. It's actually a good DC runner and even looks great for a Life-Like, despite it not being DCC-ready. I tried selling it in the past but got no takers. I figured I'd hold onto it since it was the last thing I bought from a beloved LHS right before they closed for good, so there's some sentimental value in it for me. The decoder is small enough to fit under the existing light board without any frame modification.

Anyway, I understand the basics of installing a wired decoder -- make sure the motor is totally isolated from the frame, most of all. I have Kapton tape and have been taping off the inner barrel where the motor sits. The rest is somewhat straightforward as far as where to solder.

Thing is, it has an analog light board and from running it DC, I like the brightness and the LED glow (nice golden color, not the ugly cold white from other LEDs). Plus, it has the LEDs in the correct position for the front and rear lenses, and if I did remove the analog light board, then I'd have to manually wire in some SMD LEDs + resistors.

Here's what the frame looks like (Image from the Spookshow.net entry on this loco):



So, is there a way to install this wired Digitrax decoder and use the existing light board? If so, how would I wire in the yellow/white/blue wires? And would I also have to isolate the light board from the frame? Or is it best to remove the light board and use my SMDs/resistors?

This is what the decoder looks like:


Under the streets of Los Angeles

Steveruger45

  • Crew
  • *
  • Posts: 1704
  • Gender: Male
  • Respect: +524
Re: Using Stock Analog Light Board With Wired DCC Decoder?
« Reply #1 on: September 01, 2019, 07:41:07 AM »
+1
You can use the dc board but you would have to modify the traces on it to get the lights to work with the decoder.
To my mind it’s better to keep the dc board as is and just remove it and do a fresh dcc install with leds/resistors etc.  I usually make my own pcb for this.    Then if you ever change your mind latter you can always convert the loco back to original dc.
You can get warm white leds which don’t have that blueish tint or color them with a yellow marker or you could desolder the leds off the dc board and reuse them.  This still allows you to resolder them back on the dc board if you ever want to convert back.

Here is a link that may be helpful describing some installs.   http://n-scale-dcc.blogspot.com/search/label/Decoder%3A%20TCS%20M1

The following from the above link of installs seems to be the closest to your loco.

http://n-scale-dcc.blogspot.com/search/label/Loco%3A%20Walthers%20GP38-2
« Last Edit: September 01, 2019, 09:03:10 AM by Steveruger45 »
Steve

MetroRedLine

  • Crew
  • *
  • Posts: 553
  • Gender: Male
  • Respect: +156
    • Union Pacific Vallealmar Subdivision (Facebook Page)
Re: Using Stock Analog Light Board With Wired DCC Decoder?
« Reply #2 on: September 01, 2019, 04:06:49 PM »
0
You can use the dc board but you would have to modify the traces on it to get the lights to work with the decoder.
To my mind it’s better to keep the dc board as is and just remove it and do a fresh dcc install with leds/resistors etc.  I usually make my own pcb for this.    Then if you ever change your mind latter you can always convert the loco back to original dc.
You can get warm white leds which don’t have that blueish tint or color them with a yellow marker or you could desolder the leds off the dc board and reuse them.  This still allows you to resolder them back on the dc board if you ever want to convert back.

Here is a link that may be helpful describing some installs.   http://n-scale-dcc.blogspot.com/search/label/Decoder%3A%20TCS%20M1

The following from the above link of installs seems to be the closest to your loco.

http://n-scale-dcc.blogspot.com/search/label/Loco%3A%20Walthers%20GP38-2

Thanks! I've actually seen this page years ago but disregarded it because I was too timid to deal with wired decoders at the time. This is a great help!
Under the streets of Los Angeles

MetroRedLine

  • Crew
  • *
  • Posts: 553
  • Gender: Male
  • Respect: +156
    • Union Pacific Vallealmar Subdivision (Facebook Page)
Re: Using Stock Analog Light Board With Wired DCC Decoder?
« Reply #3 on: September 02, 2019, 08:59:37 PM »
0
Okay, I'm following the directions on the wired install of the TCS decoder into the LL GP38-2. The wires are exactly the same as my Digitrax DZ126.
It says to remove all the components on the light board and re-use two of the resistors into new locations. So what's the best way to remove the components and not botch this job?

Under the streets of Los Angeles