Troller dual power pack

[sd75i]

Turned power pack off and unplugged it .   Plugged back in and turned it back on and turned throttle up and no track voltage light.  Grrrrrr

[peteski]

How's that for a fix?!   

I'm wondering if the contacts on the brake switch are oxidized so it is not conducting in the normal (not brake) position.  That would keep the throttle from working. Is the behavior the same on both throttles?

You can safely bypass the brake switch by shorting the middle and right terminals together.

You can also try to clean the switch contacts by turning the brake on and off lots of times.

The track voltage pilot light behaves as expected. It visually shows you the variable voltage by changing brightness.

[sd75i]

  Not getting anything on right side but I'll try that shorting technique.  2 blacks coming out from bottom of each transformer and one each tied together from plug to on off switch and two together with other part of the plug.

[sd75i]

Ok brake switch wiggles and now both track voltage lights on bright but not going off with throttle turned off?

[peteski]

Ok brake switch wiggles and now both track voltage lights on bright but not going off with throttle turned off?

I assume that the momentum is turned off.  I think that once the brake switch works properly then everything will work correctly.  If you want, we will totally bypass the brake switch to see if the throttle behaves better. Unsolder the wire from the middle terminal of the brake switch and solder it to the right terminal. So you will have 2 wires on the right terminal.  See how the throttle behaves after that.

[mmagliaro]

It's the spring-loaded brake switch? 

 

Okay.  That's something we should have checked as fundamentally as the fuses, before messing with everything else.

The same thing is so common in audio equipment, guitar amps, etc.  Dirty switch, dirty plugs/jacks.  And with equipment
this old, it is not surprising at all.

[sd75i]

  Yes brake switch is spring loaded.  I felt like giving up yesterday after trying to draw diagram and can't get a pic underneath circuit board!  Thanks for sticking with me on this.  Your patience is much appreciated!  I think messing with brake switch may have done the trick.    I will try the wire from middle to right side later today!!  Truly awesome!!!  Thank you very much!!!

[peteski]

  Yes brake switch is spring loaded.  I felt like giving up yesterday after trying to draw diagram and can't get a pic underneath circuit board!  Thanks for sticking with me on this.  Your patience is much appreciated!  I think messing with brake switch may have done the trick.    I will try the wire from middle to right side later today!!  Truly awesome!!!  Thank you very much!!!

Hopefully now we'll have no need to look at the circuit board.  I think that this has been slightly frustrating but fun  remote-troubleshooting experience for all the participants in this thread. I know it has been for me. 

[Kisatchie]

...I think that this has been slightly frustrating but fun  remote-troubleshooting experience for all the participants in this thread. I know it has been for me. 

Hmm... Kiz has been
totally lost reading
this thread...

[mmagliaro]

Hopefully now we'll have no need to look at the circuit board.  I think that this has been slightly frustrating but fun  remote-troubleshooting experience for all the participants in this thread. I know it has been for me. 

Yup... Frustrating maybe, but certainly an interesting adventure.  My hat is off to sd75i for hanging in, being persistent, and
being patient with all of us.  Most of all, I'm glad his throttle works.

[sd75i]

   Ok more to figure out but I think we are over the hump.  Yesterday I was able to hook power pack up to track.  Momentum works which I really like.  Hooked both throttles up one at a time and had some success running trains but sometimes stopping didn't work too well!  The brake switch did not stop trains at all unless throttle was stuck full with it turned completely off.  Is this just a simple replace brake switch with new one? 

[peteski]

I think it is the switch.  When you go into the brake mode all the switch does is to connect the speed control circuit to ground through a high value resistor which slowly brings the voltage down.  If all the wires are soldered back at their original locations on the switch you could verify if it is the switch causing the problem.  If you short the center terminal switch with the left one (on your photo) which has a resistor soldered to it (the small cylinder with color stripes on it). That should activate the brake.

It seems like for whatever reason (maybe it is a different brand switch) only the brake switch contacts oxidized inside the switch causing intermittent (or no) contact between the terminals.  In my electronic experience spring-loaded slide-switches are very rare (I can't remember last time I encountered one before seeing this one).

If you are handy, you could try to take the switch apart and clean/polish all the internal contact areas. That would most likely fix it.  Or replace it with a new switch.

[OldEastRR]

And the good guys save the day just before the thread ends! Jus like an action thriller! Yay!

[sd75i]

  You are right!  So far I can't find a spring slide switch.  I went to that mouser website, but it has about 750,000 options to narrow down switch and I don't know one thing about switch.  Tackling taking apart switch sounds pretty interesting.

[mmagliaro]

If you can't disassemble or clean that switch with success, you may have to replace it with something other than
a slide switch.

A momentary toggle would work (something like this  http://www.mpja.com/DPDT-On-Off-Momentary-Mini-Toggle-Switch/productinfo/16074+SW/  )
But you'll have to cobble the mounting a little.  In your case, a mini toggle might just fit through the rectangular hole left by
the slide switch, and the nut/washer ought to just go on and hold it fine.
My switch example is a DPDT and your brake switch is just an SPDT, but that won't matter.  You just won't use
one set of contacts on the DPDT.  You might find it easier to find a momentary DPDT than SPDT anyway.