[MMER1116]

Restoration is going well. Trucks are wired and working properly. Cannot get any sound. It was working with the decoder attached. I have soldered a connector onto the speaker leads and plugged them into the board. Were the speakers plugged directly onto the main board, or, is there a sound module that is now gone?

Greg, can you direct me where to go to edit the post. I would like to learn posting correctly.

Thanks again,

Mike

 

[Greg Elmassian]

3 dots in the upper right hand corner of your post. Interesting adoption by the Internet and software people, 3 dots in publishing is called an "ellipsis" which means some words left out... like in a quote where some words are left out in the middle.

Began to mean "more text here" and the more text turned into "a menu here"... so always look for an "ellipsis" or it has also been expressed as 3 horizontal lines to find hidden menus.

Notice there is a ellipsis at the right hand side of the "banner" that says "mylargescale" at the top of the page too.

Greg

 

[MMER1116]

3 dots in the upper right hand corner of your post. Interesting adoption by the Internet and software people, 3 dots in publishing is called an "ellipsis" which means some words left out... like in a quote where some words are left out in the middle.

Began to mean "more text here" and the more text turned into "a menu here"... so always look for an "ellipsis" or it has also been expressed as 3 horizontal lines to find hidden menus.

Notice there is a ellipsis at the right hand side of the "banner" that says "mylargescale" at the top of the page too.

Greg

All set, cleaned up.

 

[MMER1116]

Mike,

If you are just interested in restoring your SD40-2 loco to its original factory wired connections, I had occasion to do this with a used loco I had purchased. (A few posts back Greg E. had provided a link to my "vignette" (article) that includes doing just that.)

Illustrated below is how I had received my Union Pacific SD40-2

Note that the "PICK2" color code wires on the switch board (shown above) were reversed on my SD40-2 like they are in your picture!

Within the "vignette", take a look at section concerning the switch board as this may be of help. (I corrected the PICK2 wires and also had to make new cables with appropriate connectors because they had been cut off and missing from the switch board.)
Click on "USA Trains SD40-2 Experiences - Switch Board and Cables"
(You will, also, see how the trucks are wired.)

I did make one difference with respect to the factory truck wiring connections to improve serviceability - shown and described below.

-Ted

Ted,
As I look at the pictures shown on the link, what is the small circuit board in the loco's center? I assume it is either a sound board or a smoke unit interface?

Mine is gone.

 

[Ted Doskaris]

Mike,
Yes, the middle PWB is the electronics for the smoke unit. In this example the older type smoke unit itself does not include a fan like the newer USA Trains units have.

-Ted

 

[Greg Elmassian]

Note that Teds pictures are the early style boards, the smoke units, the smoke power boards and the main board are all slightly different in later models.

Your unit seems to be the early style based on looking at the main board.

By the way, do not EVER put both regulators on the same weight, they are different polarities, and attaching them to the same weight will cause a short and damage things.

Greg

 

[MMER1116]

Thanks to all for your help and input! Locomotive is complete, re-assembled, and running correctly.

When I open the second SD40-2 that is wired with a NCE GWire receiver that I have the transmitter for, should I just continue this post or start a new one?

What I know so far: When the loco gets set on a DC track, it does nothing. I followed the manual and reset the address. I get forward, reverse, engine sound and bell. What I can't get is wheel speed past a slow crawl. Now that I better understand how to remove the shells, I am going to pull the top off and look what is installed.

Mike

 

[MMER1116]

Thanks to all for your help and input! Locomotive is complete, re-assembled, and running correctly.

When I open the second SD40-2 that is wired with a NCE GWire receiver that I have the transmitter for, should I just continue this post or start a new one?

What I know so far: When the loco gets set on a DC track, it does nothing. I followed the manual and reset the address. I get forward, reverse, engine sound and bell. What I can't get is wheel speed past a slow crawl. Now that I better understand how to remove the shells, I am going to pull the top off and look what is installed.

Mike

I have started on SD40-2 number 2. This appears to be the later version, I think. I am baffled that I did get the Loco to run using the GWire controller, now I get nothing? Once again, it will be coverted back to DC operation. I already know how to correctly re-attach the motors to the control board. They have been tested and work correctly.

How does the sound work, it is currently wired to the decoder? On the last one, I made the mistake of plugging the speaker directly to the control board. After seeing the smoke rising from the speaker I figured that was a bad move.

Pictures attached.

 

[Greg Elmassian]

So are you removing the QSI units? They do DCC and DC and Gwire/Airwire.

If you have the wireless receiver plugged in, they get their commands from Gwire/airwire from the little receiver board.

Unplug the board, and you get DCC or DC from the track pickups.

Let me know what your goal is. I can use one extra receiver if you are giving up the Gwire/Airwire.

have you read my pages on my sit about QSI, Gwire, etc.?

Greg

 

[MMER1116]

So are you removing the QSI units? They do DCC and DC and Gwire/Airwire.

If you have the wireless receiver plugged in, they get their commands from Gwire/airwire from the little receiver board.

Unplug the board, and you get DCC or DC from the track pickups.

Let me know what your goal is. I can use one extra receiver if you are giving up the Gwire/Airwire.

have you read my pages on my sit about QSI, Gwire, etc.?

Greg

I am all steam, the SD40's will not be staying. The goal is to sell off the diesels and keep the steamers. The locos need to run correctly or they will be sold for parts. Basic analog DC operation is the goal with lights and sound.

When I checked out all the locos that came in several boxes, (4) ran on DC. This one did nothing, I started playing with the GWire and got sound and some movement front and back. I saved it for last. Now, I put it on the same test stand and get nothing. As mentioned, I unplugged the receiver, still nothing.

Checked the test track - +20v forward -20v reverse.

Here is where it gets really weird, when I check the two power feeds into the decoder (the two outer screw terminals) it measures 0 volts. I removed the wires and checked again, 0 volts.

Next, checked each lead to the track. Each one shows 0 volts to the near track AND each one shows +19.v to the far track. Same polarity.

Who ever did the install soldered one wire to the motor switch terminal on the main board, the other wire is soldered to a leg of a motor diode.

Neither motor connection is plugged into the main board, both motors are tied together and attached to the decoder. The front pickups plug into the main board.

Attached is a picture of the receiver, is this what you are looking for?

 

[Greg Elmassian]

Yeah. I'm short a receiver.

The QSI should function fine on DC.

Leave the flex cable unplugged, and it should respond to DC track power.

If you get stuck, it might need reprogramming, If you pay shipping I'll program them for you for free, with the sound file of your choice.

Greg

 

[MMER1116]

Yeah. I'm short a receiver.

The QSI should function fine on DC.

Leave the flex cable unplugged, and it should respond to DC track power.

If you get stuck, it might need reprogramming, If you pay shipping I'll program them for you for free, with the sound file of your choice.

Greg

I will send you the receiver out of SD40 #1, once I get SD40 #2 running I will send that receiver, as well.

I still think I have a wiring problem seeing that the two power wires that feed the decoder are at 0 volts. Could I test this by running a wire from each track to the decoder? If I do that, is polarity important?

 

[Greg Elmassian]

Yes, polarity does not matter. Double check the wiring, the outer terminals are track power.

Maybe this was set for battery and track pickups are disconnected.

check the "quick and dirty" method here: https://elmassian.com/index.php/dcc/dcc-installation-overview

check the QSI wiring here: https://elmassian.com/index.php/lar...aamp-tips/usat-motive-power/f3/f3-dcc-install

Double check the QSI wiring here: https://elmassian.com/index.php/dcc/specific-manufacturers/qsi-equipment/qsi-revolution-magnum

Greg