Re: US trains SD70Mac problem

Bill Kohler

BTW – The board with the antenna is the G-Wire receiver and the rotary switch is a channel selector for radio channels 0 to 7.
Bill Kohler
CEO & Chief Engineer
Greenbrier, Cheat & Elk RR

You're never too old to enjoy a happy childhood!

Sent: Wednesday, April 11, 2018 10:51 PM
Subject: Re: [QSIndustries] US trains SD70Mac problem

Download this to see the connection diagram on the 2nd page.
Unfortunately, this is a very simple connection guide, not the more detailed instructions that came with the Titan large scale decoders.
On a QSI Titan Magnum, the CV is 56.1, bit 0=0 for rail DCC; bit 0=1 for G-Wire/AirWire.
But if it is already set to 1, you can’t address it from a DCC programmer – only from a G-Wire or AirWire transmitter...
With a Titan Magnum, there is a simple procedure to power up with a reed switch connecting one input to ground.
I am not finding more than the above connection diagram for the Quantum Magnum, but it does have a connector - P1 – reed switch input for volume.
Assuming this works the same as the Titan Magnum, here’s the procedure:
  1. Connect a reed switch (or a jumper wire) across pins 1 & 2 of the ‘P1 VOL’ input connector.
  2. Power up the decoder and watch the headlight.
  3. At 3 seconds, it will blink once slowly..
  4. At 6 seconds, it will blink twice more rapidly.
  5. If you remove the wire after the first slow blink, then power down and back up, it should be in track DCC mode and you can address it with a DCC programmer.
  6. If you remove the wire after the second set of rapid blinks, it will be in G-Wire/AirWire radio mode.
Good luck.
Bill Kohler
CEO & Chief Engineer
Greenbrier, Cheat & Elk RR

You're never too old to enjoy a happy childhood!
Sent: Wednesday, April 11, 2018 10:08 PM
Subject: Re: [QSIndustries] US trains SD70Mac problem
What you have is a QSI Quantum Magnum decoder with a G-Wire radio receiver connected via the flat ribbon.
The QSI decoder will only listen to EITHER the G-Wire OR DCC from the track, but not both. Clearly it is set for G-Wire at the moment...
If you do not have either a G-Wire (NCE) transmitter or an Airwire transmitter, you must do a reset on the decoder to get its attention to track DCC.
Since that is a Quantum Magnum, not a Titan, I have to dig a bit to come up with the reset procedure.
I’ve been doing it for ages on my Titans, but my one loco that still has a Magnum hasn’t been serviced in a while...
Stay tuned...
Bill Kohler
CEO & Chief Engineer
Greenbrier, Cheat & Elk RR

You're never too old to enjoy a happy childhood!
Sent: Wednesday, April 11, 2018 9:07 PM
Subject: [QSIndustries] US trains SD70Mac problem

One of our operators brought a friends G scale US Trains SD70MAC for me to look at today. This locomotive was given to his friend and his friend wants to make it a static display with only lights and sound working. As he does not have a layout. The problem is the lights and sound are not working. So here is what we tried to do  no avail.

I hooked it up to my MRC decoder doctor. When I appied power to the test track the ditch lights and the cab light came on but no soundl. I then tried to read the address. The Decoder Doctor could not read the decoder. We hooked it up to my buddies Digitax system and it told us there is not a decoder installed. It returned a "No-d" error. I did not check any voltages as I figured since the ditch lights were coming on , the voltage was there. We took the shell off.

Inside we found several boards, none of which I recoginized. One board appears to be a controller board because it has 4 different switchs on it. Motor, lights, sound and smoke.  For some reason, the sound switch was glued in the on position. There was also a small board that I thought may have been the decoder. A smoke unit board and what appears to be an antenna sensitivity baord. I think it is an antenna board because there is a a short piece wire soldered to a pad that says antenna. The antenna board plugs into the "decoder" board with a flat ribbon cable. After finding the antenna board, my bud thinks thr locomotive might be controlled byt someones propritary controll system via straight RF. And for some reason, someon has swapped the front to back wiring for the contact shoes. The front set of wires is soldered to the rear pad on the controller board and the rear set of wires is soldered to the front pad on the controller board. No clue as to why this was done. There are no markings on either of the boards that indicate who may have built them. The only indication that it has QSI electronics installed is a sticker on the board stating that the address is 84.

I have posted pictures in the phot section of thse two baords.

So here are the questions.

Does anybody recognize either of the boards I have pictures of? Is this a NON DCC system? Who's controller might work with the locomotive. Is there an inexpensive way to make the lights and sound work without the motor running.
Thanks y'all,

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