Any Successful MRC 1636 Installs Out There

Discussion in 'DCC & Electronics' started by ScratchyAngel, May 16, 2008.

  1. ScratchyAngel

    ScratchyAngel Member

    Well, I wanted sound.

    I got a Prodigy Express on eBay. I got an Atlas U25B and successfully sent off a frame to Aztec, and almost by teleportation got the exchanged milled frame right back.

    I was thrilled, the speaker fit the milling perfectly. I slid the decoder in. I ran the speaker wires under the decoder then down through the part of the frame with a little black plastic where the motor ends. I screwed the frame back together. Popped it on the track. Lights, quiet rumbling of the motor. A bit quiet, but I thought maybe the recommended resistor was just holding down the volume. Lights go on and off, horns and bell work. Woo hoo. Then a bit of throttle and it sits. Change direction the lights flip as expected, still no motion.

    Boo hoo.

    Disconnect DCC, hook up a DC throttle, and back and forth she goes. Rehook up DCC, sound, no movement then the board feels hot to the touch as I check the connections. Several tear downs and reassembles and then try without the resistor, now no sound SDVA whenever I hook it up. It looks like one of the tiny wires to the speaker lost its insulation, then it breaks.

    I have a second one, which was supposed to go into another loco. Before I can even get this one in the frame one of the speaker wires breaks from the solder. I resolder it, this one gives lights and sounds for exactly one second before going dead as the other did.

    I'm fairly sure I let the smoke out of them... $120 down the toilet. I really would like at least one loco with sound, so I'm actually stupid enough to think about ordering a 3rd, but I'm just wondering if someone out there has actually successfully gotten one of these babies working before I try again.

    Some days, it just doesn't pay to get up.

  2. UP SD40-2

    UP SD40-2 Senior Member

    Jason, this sound decoder is a "snap in" type for N scale, right? Walther's #500-1636

    at first it sounded like there was no contact being made to BOTH sides of the trucks, that would make the lights work, but not enable the engine to move. after reading the rest of your problems though, i am puzzled because it sounds like the decoders have been fried out:eeki::frowns: .

    i am in HO, so i am kinda clueless as to whats going on:oops: (i have never used a "snap in" type sound decoder) . i thought to ask if you tried to program it on the program track, but if the lights are/were working properly, it wouldn't help to do that, as obviously the system IS/WAS reading the decoder.

    if you don't get a response on here, try calling MRC's tech department, i have done this when i first got my PA, and got excellent service:thumb: .

    :deano: -Deano
  3. UP SD40-2

    UP SD40-2 Senior Member

    i could be totally wrong on this:rolleyes: , but the more i think on your problem, it seems somewhere the contact wire to one side of the trucks is broken, or shorting out on something, just a thought, would be worth checking:winki: .

    :deano: -Deano
  4. ScratchyAngel

    ScratchyAngel Member

    Yeah, that was my first thought, and hence some of the disassembly and reassembly. The motor makes contact to the little board with two little strips, and I thought they might be shorting, or that the strips to contact the trucks were off. What's a bit more disturbing is how incredibly fragile the little speaker wires are, and that one of them on the first decoder seemed to lose it's micro-thin insulation (the wires are copper colored and seem almost hair thin, but it had turned silvery over the section that seemed "fried"). I'll definitely try to call MRC sometime next week.

    The snap-in part seems absolutely idiot-proof, so I'm thinking somehow the speaker wires are where I went awry as far as blowing it. I definitely suspected contact issues, but whenever I put the old light-board back in it ran like a champ on DC (and still does).
  5. ScratchyAngel

    ScratchyAngel Member

    Update: the smoke is not out of them, but there's one broken speaker wire and on the other decoder one lead now disconnected from the board, and it's a ___ to resolder.

    I was able to get it to move both ways, it seems the two little contacts with the bottom of the board are extremely picky. If they aren't bent just so to push hard enough, no good contact. If they move just so, they create the short I was seeing. Snap-in or drop-in my eye. I'll try to eventually take a picture of the offending places, and hopefully will have some kind of update if there's any joy in getting the speaker wire soldered back on.wall1wall1wall1wall1wall1
  6. woodone

    woodone Member

    replace the wire

    Get some mangnet wire. #36 should do the trick. Small tip solder iron and replace the wire. You will not have to strip the wire just pretin with the hot solder iron, and it will melt the lacquer insulation. You will jut have to touch the wire where you want it and it should solder it self there.
    You want a hop tip and just touch the wire long enough to flow the solder. You don't want to to hold the hot tip on the board very long. A count of one-two and your out of there.
    Happy soldering:thumb:

Share This Page