Soldering assistance required

[strobez2018]

Hello forums users!!

I'm looking for a bit of help with soldering a Bachmann controller (DC, not DCC).

It's "item number" is 46605-UK.

The main issue is that when working on it two of the wires became detached from their soldered positions.

I've attached an image of the circuit board with the wires hanging free.

Image 01 shows that it is the yellow and the orange wires that have become detached. See below.

And here's another link to a pic in my Google Photos - https://photos.app.goo.gl/QzKdBvfJF8gwqk287

It shows the full PCB circuit.

Also, see this pic - https://photos.app.goo.gl/h6Xxo3yr5MNTBbp46

It shows the controller external view so you can see what unit this really is.

(I failed to upload more than one attachment here, so I resorted to Google Photos)

We did approach Bachmann Support but they said that they didn't support it or have any wiring diagrams etc.

So we're hoping that someone helpful might know the correct position of the wires.

The work that we were doing was to replace two blown capacitors. This is not really relevant to to the issue I'm looking for help with though.

I have done a lot of Googling for circuit diagrams and images of the internal wiring but cannot find anything useful.

We've since learned that in future, we'll take pictures of any delicate internal wiring before going to work on it!

Many thanks in advance. Any help would be greatly appreciated.

Steve Roberts

[Emettman]

My approach would be crude and simple...
I'd attach tag wires of a few inches to the board where the wires had broken
(that gives more room to work, anyway)
and just try them both ways round (twisted wire connection, initially.)
You should have no risk or problem at a low controller setting seeing which way round a loco likes better.

Chris.

[Mountain]

It would help if someone else had the same controller to look at, as long as those wires dont break as well!
I've never had a Bachmann DC controller. Only once owned the DCC controller which was nice and simple to operate, though a bit limiting in practical use unless one only owned a few locos on a small layout.

[Admin4]

Mines not identical but looks close enough

I’ve just pulled it to bits so hope it helps

[Admin4]

Inside - few angles as I didn’t want to go further if this is OK

[Ironduke]

Looks like there are two variants of the PCB.

Steve, is the green wire still attached in that first photo? If so I would guess that the other two wires go next to it. I mean, if I was designing a circuit board I'd put the three legs of the potentiometer in a row next to each other, but it looks like just about anything goes with that circuit board design. What a mess!
Alex's version is even worse but at least it has some text to mark where things go.

[Bufferstop]

Can you see the other side of the board where the green wire is soldered in. Whatever it looks like somewhere there will be two similar looking terminations with no wire on the other side of the board. More than that is hard to say without one in your hand. The two units were obviously made in different workshops as the soldering style is completely different. Although it doesn't look so neat the wire terminations in the second unit are likely to prove more reliable when you open it up, as any strain on the wires will happen in the soldered section, not on the point where the wire strippers bit when the insulation was removed. As Ironduke says "what a mess." The circuit board in the Gaugemaster handhelds and panel mounts is a third or quarter the size and manages to look neat and tidy and find room for some identification marks for the connections.

[strobez2018]

Thankyou for all your suggestions everybody (especially to alex3410 for taking his unit apart, photographing it and uploading the pictures - I really appreciate your time!)

I shall make further investigations from all your suggestions.

And I'll try let you know how we get on.

Many thanks

Steve