And THAT is how simple it would be for QSI to 'fix' the inrush current problem with their sound decoders. The diode allows for the capacitor to charge up at a reduced rate through the resistor, yet discharge as quickly as needed when there is no input power. If you run huge strings of cars with that circuit you may have to adjust the resistor slightly higher to slow down the inrush, at the expense of longer charge times, but unless you have multiple dozens of lighted cars in the same power district there should be no problems.
Tsunami decoders now also have a keep-alive capacitor, if they haven't already incorporated somethign of the like to mitigate the inrush problem, the same thing would work on theirs.
Once I get back up and running I guess I'll have to try it and verify that it won't blow up the decoder
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I run my Bachmann Spectrum Passenger cars on DCC all the time. Absolutely no problems. I believe the bulbs are in series and rated for 16 Volts.
Loathar: Bachmann is going out of passenger car production! Grab them while you can!
To drop the flicker, you can use the following wire diagram: This will dim the lights a little on the spectrum cars, but will also increase their lifetime considerably! It's about 4 tiny components and ~$3/car
Larger capacitors will help reduce flicker!
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
I like mine. The power pickups are already there. So it wouldn't be much of a problem to add a bulb or two in the car ends. The roof comes off easily. But that would increase the current draw, if that's a factor in your layout.
IIRC, the Bachmann couplers did not have knuckle springs. I changed them out for Kadee couplers and have no problems at all with them coming uncoupled. The newer Kadee shelf couplers would be even better, but these are very difficult to uncouple.
I have put my fair share of miles on them without any issues EXCEPT for not caring alot for the stock couplers on them and the forementioned flicker. I havent run them for 2 years but I recall they occationally uncoupled.
doug aka dansgrandpapa
How do you guys like those cars? I've been looking at a set of their heavy weights. Can't beat the price.Hope they start to produce them again.
Yes, they will be okay on DCC. I have the complete Santa Fe Heavyweight set of Bachmann Specturm passenger cars with interiors and lighting purchased in the 1990's and run them on a DCC layout with no problems other than the inevitable flickering from dirty wheels or dirty track.
I think the bulbs used by Bachmann are rated for 16 Volts, which is within the DCC track voltage range of most systems.
The biggest drawback is the way they have only one bulb in the center of the car and plastic light guides that are supposed to carry the light to the ends. As with all other systems of this type, you wind up with a very bright center portion and dim ends.
I have 6 H.O. bach spectrum heavyweight passenger cars probably made in the mid 90's. They already have lighting from the box for DC. Has anyone placed these on a DCC layout yet or tried throwing a decoder in them for light control? Would I be correct in assuming the light system itself to be acceptable at DCC voltage?
Thanks in advance!
Doug