Prodigy Advance 2 issues - Possessed or just a bad switch?

[reasearchhound]

Wrote not long ago about my extending a spur into a connection to my main line which involved a reverse loop, new handmade turnouts (FastTrack), Tortois switch machines, and the electrical gremlins I was being beset by.

Issues involved lots of stuff to the point it was confusing as to what was going on - track issues, decoders, the Prodigy unit? Through some experimenting, is seems the on/off switch on my Prodigy is acting up. Will not be getting power to my track and then in manipulating the switch, suddenly I do. Can a wonky switch be the cause of all sorts of electrical issues - not just the machine not outright working, but in causing all sorts of issues like intermittent start/stopping, short readings, and a locomotive sitting there emitting a ticking sound but not doing anything else, plus troubles trying to reset the decoder to factory settings? Reminds me of a car battery that is bad (but not dead) that causes all sorts of weird stuff to happen that one would never associate with a battery issue.

Seems like I read somewhere online where a guy was advised by MRC to remove the cover to his base unit and clean the connections to the switch. But I can't relocate the post and I don't see how to open it up. I also don't want to do anything which will cause MRC to not want to fix it.

Have a call into them tomorrow morning to run all this by them but thought I would toss it out here and see what others think.

[RR_Mel]

I’ve had my Prodigy since 2006 and never had any problems.  I have a loop/wye but no automatic switching stuff, I manually take care of the polarity issues.

I turn it on and off probably as much as the next guy and never had a problem with the switch in 15 years.

My layout is wired for a DC block operation and I run dual mode, DC or DCC.  I simply connected the Prodigy to the DC track power (it is interlocked so that only one controller can be connected at a time) and so far it has worked 100% of the time for 15 years.

The switch on the Prodigy only turns off the controller, there is no switch on the power supply.  If the Green Pilot LED is on the switch is working OK.  I turn off the power supply with a line switch at the wall power.
 

Mel



 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

[rrinker]

 On thing that can get you with a Fast Tracks style turnout is that when the copper clad boards are sheared to make PCM ties, little fuzzes of copper can get jammed into the cut line. So if you only file the gap through the copper on one side, you can have an intermittant short through the back side of the board. You should file gaps on both sides, and also lightly sand the edge of each tie to make sure there is no lingering bit of copper to cause grief. 
 ANd verify that none of the rail gaps have closed up. That shouldn't happen - since the rails are solidly soldered in place. If you are reading this and wondering what gaps - check the build instructions. Gaps are required in the diverging frog rails. You CAN change where the gaps are filed in the PCB ties and put the diverging rail track gaps further out, but then it is absolutely critical to power the frog since there will be a large dead section.

                                          --Randy

 

[Overmod]

I'd consider a shot of electrical contact cleaner into the switch itself, followed by working it backward and forward 20 or 30 times -- more if necessary.

There are also switch 'issues' that clean internal contacts won't help; if you aren't comfortable opening or removing the switch (or the unit is still in warranty) you might be lookin' at having them do it.

I have seen heavy 120V contactors 'fail' when a small piece of ant exoskeleton chitin found its way between the hard-faced contacts.  Strange things can affect mechanical switches ... and then there are those that are electronic, which I presume these aren't.

[hornblower]

Like Mel, I use an MRC Prodigy Advance (not squared) system to power my 10' by 19' double deck HO scale layout and have not had any problems with the MRC system in the 10+ years it has been powering the layout.  I have three (3) reversing sections controlled by Digitrax AR1 auto reverse modules (one "wye" and two turntables) and all work as intended.  I would suspect that something in your latest trackwork is causing the problem(s).  As previously noted, make sure to gap the PC ties on both sides, especially if you are using track nails to secure your turnouts.  Use of such nails without gapping the underside of the PC ties could create a direct (and possibly intermittent) short across the rails.  If you can isolate the new section of track from the original layout, do so and test the original portion of the layout for the described gremlins.  If proper operation is restored, go back to the new section and re-check everything for shorts or other wiring problems.

[reasearchhound]

I actually sprayed some contact cleaner into the switch and that's when I noticed everything suddenly working fine. Really thought I had solved the issue but then in an hour or so it would be acting up again. My thought was that the contact solution initially helps but then the switch stops working after the spray evaporates out. I have not tried spraying and then moving the switches that many times afterwards but will do so.

Spoke with MRC and they want me to send it in. This will be the second time having to do so and with my MRC unit being around 15 years old, I am seriously considering getting a new system instead. This is my prime model railroading time and am frustrated I can't get to many things on my list due to this happening. 

[reasearchhound]

So, went back and checked connections, sprayed contact cleaner into the MRC switch and all three of my test locos worked flawlessly - for awhile. Then loco stopped, stuttered a few times (there are super clean wheels and track so those are not the issue). Shut unit off, sprayed switch, turned unit on and everything functions "perfectly". Run locos for awhile, same thing happens again;  stall, shut off, spray, turn on = operates.

 

And to be clear, I went back and disconnected all of my new track work, turnouts, Tortoise machines, and reversing devices so as to eliminate any potential issues from any of those. Everything new has been either removed or isolated. The above results are being obtained on a section of track that has been as is for fifteen years.

 

I either get the switch fixed, or buy a new control unit. I am leaning towards the latter.

[RR_Mel]

Does the Green LED flicker or go off when it quits?  The switch carries the full current from the power supply and might be defective.  Try more cleaner and working the switch a lot to clean the contacts.

The swtich can easily be replaced by you for about a buck, if your planing on replacing your controller nothing to loose by trying.

 

Mel



 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

[reasearchhound]

Thanks - I am pretty sure the switch is the villian here. Green light seems to work pretty much as it's supposed to if everything else is functioning.

Seems like I remember another thread/post where MRC actually told the modeler to open up the base unit and check the connections on the switch. I have tried to see how to open it but see no opbvious way and didn't want to do any damage. Anyone having done it and willing to give me a tip would be appreciated. I know that replacing the switch likely wouldn't be a big deal. I do miss Radio Shack for situations like this.

[RR_Mel]

OK, here’s my jab.

                               Click to enlarge

Four Philips screws in the bottom.

Top and bottom housing shells just pop off.  The only thing connected to the chassis is the fan and it has a JST connector on red and black wires.



Looks like a standard PCB (Printed Circuit Board mount) DPDT Slide Switch.

OK? Now do it to it.

 

Mel



 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

[Overmod]

Mel, give him one more picture, with the plastic switch 'topper' taken off the physical top of the switch.  He might make the mistake of thinking that's part of the physical switch and have trouble getting contact cleaner down into the actual mechanism, or ordering the correct replacement if it comes to that.

[rrinker]

 Wait - an MRC power device that has ordinary screws and not special security type like on most of their power packs? Not that I don't have a set with all those oddball bits (actually I somehow ended up with TWO of the same set - so one for the train bench, one for the electronics bench), but not everyone has those things. But simple common Philips head screws? That's sort of a first.

                                         --Randy

 

[reasearchhound]

Got mine open and oddly, there is no fan. Maybe they forgot to put it back in the last time I sent it in for repairs.

Tried spraying more contact cleaner in from both sides and worked it back and forth quite a few times but no change once the cleaner evaporated.

Anyway, will get a few switches and look into replacing the one that is there. If I screw it up I have a new NCR unit due to arrive Thursday. 

Thanks for all the advice and pics (Mel) very much appreciated.

[RR_Mel]

Thanks Overmod, slipped up on that one.

Won’t hurt to check the solder joints on the bottom, I’ve seen a lot better soldering.



This one is pretty old Randy.  This was a good exercise, now I know what mine looks like on the inside.

 

Mel


 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

[rrinker]

 No fan? That is probably why it stops working after a while, then works again. It's overheating. Generally, if something is designed to work with a fan, it won't operate properly without one. Try operating it with the case off, more air can flow over the heat sinks that way. Just don't set the bare board down on the layout where it could touch a piece of track. Set it on a piece of cardboard or other non-conductive surface to do the test. 

                             --Randy

 

[RR_Mel]

I’ve never heard the fan come on in mine Randy, I think the fan must be temperature controlled.  I rarely see my ammeter at 2 amps, three locomotives will run at about 1.8 amps and I very rarely run more than three.  A pair of my super heavy E7s draw just under 1.6 amps with sound on pulling my 3½% grade with eleven 9oz passenger cars.   

 

Mel



 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

[rrinker]

 I was going to say maybe it's variable speed, but with only 2 wires, not likely - although MRC does like to do things 'different' 

                                    --Randy

 

[hornblower]

Like Mel, I have never heard the fan in my MRC Prodigy Advance unit run no matter how many locos I run or how hot my garage gets in summer.  

[reasearchhound]

Thought I would see if MRC would get me a switch to replace mine with so I'd know the specs were exact, but they don't sell just parts. I now have some coming from Amazon that should work fine except the knob is going to be too short - but that's a fairly easy fix.

While on the phone, I asked about the missing fan, and he said the later units did not have them. 

[reasearchhound]

Follow up post: received my new NCE control unit, hooked it up to test track and programming track and got all locomotives programmed and running great. Transferred them one at a time to main track and still all good. Went back and started reconnecting all of my suspect track areas, switch machines, and reverse loop - testing as I went along to see if everything functioned after each one was connected.

 

Everything is now completed and running great!
I did order a new on off switch for my MRC unit and will replace it just to see if that solves the problems, but for now I am busy running trains again.
Once again, thanks to all of you who took the time to respond. Very much appreciated.

Dan