I am running my HO layout with an MRC Prodigy express DCC. Of course I have experienced both dead spots due to dirty rails and shorts due to derails or turnouts thrown the wrong way but this problem is neither of those - it seems to be something inbetween! The engine will stall and the sound effects will stop but the engine will be making clicking sound apprently coming from the speaker. This has happened with engines with and without a Keep Alive capictor in them. Does anyoune have any idea what is happening and, more important, what I can due to remedy the proble. (I think this generally happens on a turnout but I can't say for sure it hasn't happened on straight track. The problem has been with me since the beginning and I thought a Keep Alive capacitor would help but it hasn't). Any help would be appreciated! thanks.
Jim in Costa Rica
Modeling freelance Northern California late 1930s
That still sounds like a short. The clicking may not be coming from the speaker by fromt he point of the short on the loco - a pickup or loose wire, for example. It's the system interrupting power, then thinkign the short is clear so it restores power only to detect a short again. Do all your locos do this or just one?? Does it happen only at one spot on the track or anywhere? These answers will help you decide where to look next.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
What brand of turnouts are you using?
Thanks Randy, for the reply. It has happened with different locomotives in different locations. Your explanation makes a certain amount of sense. The reason I had coounted out a short was because my throtle usually tells me when there is a short and in this instance it is not telling me that. I will have to observe closer if it only happens on turnouts. I have non dcc friendly turnouts so both points are powered the same polarity. Maybe I'm getting some short there.
[quote user="BMMECNYC"]
I agree with Randy. A circuit breaker tries to reset every 1-2 seconds. If that's the period of the clicking sound, it's almost certainly the power trying to come back and then the breaker immediately shutting down again. If you move the engine a few inches, what happens? If it starts running again, then yes, you have a short.
It takes an iron man to play with a toy iron horse.
What is confusing is that generally my MRC throttle registers a short and I have to shut down power to reset the system to get control back - it makes no effort to reset itself. In this case, no short is registered and and if I push the engine forward it will run again and I have control. The throttle looks normal through the whole thing. I am wondering if it could be caused by a voltage drop rather than a full short. Maybe this could be caused by a high resistance short that only dropps the power below operating levels but not a complete zero voltage short.
Pay attention to where it happens - if it happens only at the turnouts, that's classic "not DCC friendly turnouts" - the issue with the SHinohara turnouts is mainly that the open point rail is the opposite polarity from the stock rail, so if the back of a wheelset on the side of the open point rail brushes the back of the point rail - short. BUT - even when the power drops out from under it, most any loco will still move at least a little before it stops - so no, no short. Power comes back on, as soon as the loco goes to move - SHORT. And so on. So there is at no time a continuous short like putting a screwdriver across the rails, so you don't get the usual indication. You may see some flashing of the short indication on the handheld, if you watch closely. Depends on how fast the indicator reacts to the system disconnecting power.
Thanks Randy, I think that must be it. I can't think of anything else.
Thanks everybody for your help and suggestions.
Now I have to figure out if I want to rebuild all of my turnouts to be DCC friendly!
Any suggestions guys?
Would it be possible to apply an insulating paint/plastic/whatever to the back of the rail that you don't want touching the wheel???
I have absolutely no experience with this.
Dave
Current issue of MR has an article by Tony Koester on just this - fixing a Shinohara turnout that is already in place.
rrinker Current issue of MR has an article by Tony Koester on just this - fixing a Shinohara turnout that is already in place
That sounds like just the ticket. (I'm in Costa Rica and haven't recieved that issue yet but I'll be looking forward to it)
Thanks!