I'm thinking that all that is needed is to put capacitor somewhere on the board. Anyone done anything like that to make Walthers lighting kits flicker free? The cars look so much better with lighted with passengers, but because of how Walthers implements current pick up the darn things flicker like Christmas lights when train is moving. Stationary they look great.
There was great guide in the recent MR magazine on installing DCC decoder. I think that the amount of work required and cost is a bit overkill when all you want to do is turn them on or off. Plus it doesn't solve the issue of flicker. I think another guide would be in order on how to install capacitor and maybe a magnetic switch to turn the light on or off, a la Rapido cars.
I installed 4 of these kits in some Rivarossi cars about a year ago. The ones I used have a pair of metal contacts on the underside of the body which make contact with a pair of screws on the truck frames.
Mine hardly flicker at all. Unfortunately, that's because they seldom even come on anymore. They were pretty good for a while, but this method of making the electrical connection is just terrible. I tried wedging a small piece of plastic under the metal plates to raise them up a bit, but that was only of marginal value. I think the right thing to do is get some very thin wire (like leftover wire from Miniatronics bulbs or from decoders after installation) and hard-wiring the trucks to the contacts. These metal plates don't take solder very well, though, so I may need to completely disassemble the cars to do it right.
A capacitor isn't going to help, or it won't help for long. The pickups are just to unreliable.
It takes an iron man to play with a toy iron horse.
I drew this up a year ago. Even though it says "Bachmann cars" there's zero reason why you can't use it for walther's heavyweights.
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
You could also by the DC version of the light bar. It's essentially the same as the circuit above. (Hence why they are more expensive)
They also have LED light bars that you can sue with a battery pack if you can't get good electrical pick-up.
Springfield PA
DigitalGrifin thanks for the help. I actually ended up using DC version on the Vista dome since Walthers doesn't make a DCC. For the life of me I couldn't get Walthers "tech support" tell me if it was ok to use their DC kit on DCC system, but I took a chance after someone on this board told me I could. I did notice two thinks about DC kit though: it's a lot brighter than DCC lighting kit - makes me think that either its more powerfull bulbs or they will burn out soon :( Another think I noticed is that DC kits flickers less frequently on the same train, but I didn't see a capacitor to justify it. You say it's the same circuit as what you drawn? So can I just buy DC kit, put a resistor for dimmer lights and put a bigger cap to eliminate flicker? What would be the value of the capacitor I need to use if I want for lights to last about a minute or more without power to guarantee no flicker. Finally what and where can i get magnetic switch? I assume I would just need to insert it between the lighting board and power leads to turn it on or off.
Finally, when lighting board is first time turned on, how do the lights behave while capacitor is "empty"? Thanks for the help.
My passenger cars (that can't fit the Rapido Kits) have the walthers DC lighting kits. The only flicker I noticed involved dirty track. I ran my locomotive over the sections that flickered and I noticed even with a normal track transformer that the voltage started to drop. I cleaned the rails with some old bottle of LGB smoke fluid (yeah it actually did work) and the flicker stopped.
If your tracks aren't dirty, and you use the DC versions of the kit, well than I don't know what else to suggest.
DragonFyreGT aka Snowball aka Nate.
WolfCreek & Iron Mountain (Keeping The Burlington Northern Alive since 1995)
"We took those Cascade Green engines for granted. Every Age. All of us. And in the blink of an eye, the era ended as quickly as it began."
trainsBuddy DigitalGrifin thanks for the help. I actually ended up using DC version on the Vista dome since Walthers doesn't make a DCC. For the life of me I couldn't get Walthers "tech support" tell me if it was ok to use their DC kit on DCC system, but I took a chance after someone on this board told me I could. I did notice two thinks about DC kit though: it's a lot brighter than DCC lighting kit - makes me think that either its more powerfull bulbs or they will burn out soon :( Another think I noticed is that DC kits flickers less frequently on the same train, but I didn't see a capacitor to justify it. You say it's the same circuit as what you drawn? So can I just buy DC kit, put a resistor for dimmer lights and put a bigger cap to eliminate flicker? What would be the value of the capacitor I need to use if I want for lights to last about a minute or more without power to guarantee no flicker. Finally what and where can i get magnetic switch? I assume I would just need to insert it between the lighting board and power leads to turn it on or off. Finally, when lighting board is first time turned on, how do the lights behave while capacitor is "empty"? Thanks for the help.
Your DC light bar should look somewhat like this one:
They might have used lower voltage higher burning bulbs for the DC version.
The larger the capacitor the better. Just make sure it's rated for at least 16 V. Capacitors unfortunately don't give you much time. They are just there to keep the lights from flickering. If you want lights to stay on a full minute with power off, then you want to use a super capacitor with leds for lighting. Super capacitors were developed by NASA and are NOT cheap. In this case it would be cheaper to buy a light bar from Rapido (battery) or Miniatronics (LED with super cap)
Miniatronics version:
http://www.walthers.com/exec/productinfo/475-100ICL01
The resistor in the circuit above (near the capacitor) prevents all the current from being sucked into the capacitor on startup. So your lights will light up fairly quickly.
But I'm not sure why you would need to worry about the power being off for a full minute. On a DCC track, power is always on, even when the train is stopped. Are you cutting the power off to the district for some reason?
Hmm you are right, i see the capacitors now in your picture. I don't have DC kit on hand so forgot the layout. The only reason I wanted a 1 minute of reserve is to guarantee flicker free operation, I know that MTH cars have 90 seconds of reserve - so how do they do it? Ok, so I can just buy this DC board and safely install it in all my cars, I wish I would have known this earlier. I only installed in Vista dome cause Walthers doesn't make one in DCC.
So I should be able replace caps to a biffer capacitors as long as it's rated for 16V or above? Why are there two caps on the board and how would I calculate capacitor rating to power reserve ratio? So based on your diagram that black chip is a rectifier? Finally do you think it's would be worth for me to swap out Walther's bulbs to LED? Walthers roof a really hard to remove without damaging the car so I want to do it as little as possible. Finally, why are there 4 resistors when there is only 3 bulbs? Thanks for they help by the way, I'm making real progress.
I'm actually put detailing of my EB cars on hold until I resolve the lighting issue.
Dmitri.
I think you're over thinking this.
When sitting still, do your lights really stay off a full minute or more? You really need to try cleaning your pickups and adjustment screws on the trucks if that is the case.
>So I should be able replace caps to a biffer capacitors as long as it's rated for 16V or above?
Yes
>Why are there two caps on the board and how would I calculate capacitor rating to power reserve ratio?
When caps are hooked in parallel, their capacitence adds. For example, if you have three caps each of 10uF with each + leg tied together, and each - leg tied together, you get 30uF of capacitence. (10 + 10 + 10)
The time a capacitor will keep a lightbulb lit is a complex problem. You would have to know how to measure the current draw of the circuit as well as differential equations as the output exponentially decays with time.
>So based on your diagram that black chip is a rectifier?
To be honest I'm not sure what that black chip does. It could be a current or voltage regulator. In all honesty it's probably a voltage regulator. Those four resistors you see aren't resistors. They are diodes. (See silver band on the end of each one) Put 4 of them together in the proper direction and you get a full bridge rectifier.
Thanks for the help. I will swing by the shop this weekend and pick up some DC light kits. The only one I have buzzes a little bit, I suspect it's the voltage regulator. Is there a way to soften it up. I didn't think those caps could be setup in series, that makes sense - I was like, what's the second cap is for?
I assume it would be safe for me to put some resistors for the bulbs. Since bulbs are identical on DC and DCC kits (5V) and DC kit has them brighter - means that they work harder on DC and therefore will burn out faster. So if I put some resistors (how would I calculate the value?) they should last longer by being a bit dimmer.
Finally were can I buy a magnetic switch so I can turn lights on and off? I assume it would look similar to what Walthers uses on their Proto 2001 engines with sound.
Rapido's passenger car light kits use battery power and a magnetic wand to turn them on and off --
The biggest drawback is the limited life of the button cells they use, or forgettng to wave the wand over the car to turn the light off.
Naturally, you have to open the car up to change a battery.
Has anyone tried the Flicker Free? I came across it some time ago and don't know how current their business is. I am intriqued to try it but have so many projects, I haven't ordered yet. Here is the link.
http://www.dccconcepts.com/index_files/DCCflickerfree.htm
So, diodes, a voltage regulator, and a super capacitor (most are only 5V, hence the regulator - when using LEDs for lights just size the resistors based on 5V for this circuit). SHould be easy enough to duplicate. Definitely needs a resistor/diode arrangment to control inrush, but something like that should keep the lights on in a passenger car for an awfulyl long time after power is turned off.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Current Walther's DC kits shut off on DCC as soon as you turn of the power. They flicker a little bit less than DCC kits in my experience. Buy I'm willing to experiment buy putting a bit bigger caps if space permits. I will see if I can put additional caps on the underside of the kit, this way I won't have to remove the factory ones.
What's are super capacitors, is that the official name?
Do you guys think it's worth cutting the stock bulbs and replacing them with LED? Just need to figure out what resistor to put in that case. I doubt there will be space on the board , so most likely will need to put resistors in line. What should I use to apply shrink wrap. As you can tell I'm a newbie to electric stuff. Should be fun. Too much work though, MTH and Athearn cars come equipped with buffered lights for almost the same MSRP :(
:)
Yup, super capacitors is what they are called. They are just VERY high value - and the higher the value the more energy they store. Ad the more they explode if the polarity is wrong or the voltage gets too high - most are rated for 5V, wheras smaller value capacitors can workdirectly on 12-16V depending on the rating. Notice in the picture it looks more like a battery. They are often used to repalce the battery on computer motherboards. Plenty of power to hold the CMOS settings even f you go weeks or months without turnng on the computerEven one LED draws several orders of magnitude more current than the CMOS on a motherboard, so you won;lt get weeks of light, but surely 10-15 minutes would not be overboard - more than enough to get over dirty trac without blinking.