Despite the lack of bass response in such a tiny speaker, there is one benefit to N scale sound over HO and alrger - you ony hear the loco when it's near you! Much more realistic than the sound fillign the room like it was played over your stereo. You generally don;t hear a real train 10 miles away, why the model? That actually sounds great ocming through that cut, bareley hearing it, then it gets lounder as it passes directly by the camera, then fades away. This si the way sound ought to be used, not "hey look my decoder's amp goes to 11!"
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
gatrhumpy,
It's different from one locomotive to the next. A locomotive with a sound decoder installed in it will have a higher Startup Voltage (or VStart) than a locomotive with just a motion decoder installed in it or none at all.
What you will have find out - by trial and error - is at what value of CV 2 (VStart) will your locomotive start out the slowest. Once you determine that you can then set CV 5 (VMax) to achieve the 83 sMPH for your SD40.
And, if you want to fine tune your locomotive even further, you can create a "customized" speed curve by entering individual values (between 0 and 255) into CV 67 thru CV 94. Most of the time, the defaults for them are more than adequate for smooth operation. I also prefer to operate my locomotives using 128 speed steps vs. 28 speed steps.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
Lower is better for slow speed.
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
Yeah, I'm going to screw around with it some more when I get home. Is a lower starting voltage better, or worse for slower speed performance?
I guess - realistically - how often do any of us run our locomotives at prototypical top speed? For me, I would strive for finding a balance between good low-speed response and acceptable or plausible top-speed.
As far as upgrading, you should be fine with just the Power Cab. If, at some point, you want to be able to move around your layout with your Power Cab more unincumbered, the SB3a is an option. Even if you unplug the Power Cab from the UTP, your train will keep operating. An additional cab would be the the least expensive alternative.
Hmmm, not sure. I did have an acceleration variable of 1, so it takes another 0.686 seconds to spool up to the designated speed.
I think I put the starting voltage as something like 10 or something like that. In the video, it did seem to jump off the line. Maybe I'll go back to the direct drive.
I'm trying to correspond the loco's max voltage with the real SD40-2's real top speed of 83 MPH. Anyone know the max voltage that corresponds to that speed?
And I love the PowerCab. Maybe in the future I'll upgrade, but I like the fact now it's compact.
Thanks for posting the video, gatrhumpy. That was fun to watch.
I know you were probably just wanting to show that you new install was indeed working. However, I was just curious how slow your Kato will go with the MRC decoder at speed step 001?
Also, how are you enjoying the Power Cab interface? Are you finding it pretty straightforward to use?
Video of the new system at work.
Anyone have a detailed picture of the updated MRC 1806 DCC sound decoder, specifically the front of the newer boards with the newer (smaller) diodes?
Interesting. Might have to do some experimentation today. :D
It would appear so - there's very little variation in typical LEDs these days, as far as max current limit.
Randy, is the LED from the old board a direct swap with the LED from the MRC decoder?
Review of the Kato loco in the most recent Model Railroad News mentioned installign this same decoder. The reviewer stated he usually swaps the LEDs because the ones on the Kato DC board are nice and bright and the MRC ones are kind of dim.
Swapping surface mount LEDs isn't a task for just anybody, you need a proper low power soldering iron with a fine tip, a magnifier, and steady hands.
Given the recent history, I will respectfully say that I think this is probably beyond your skill level at the moment. After some more practice, then you might attempt this. To be honest it's somethign I would hesitate to do and I think my soldering skills, at least when it comes to electronics, are well up there.
If the LED doesn't line up with the light pipe very well, you could try adding (and shrinking) a short section of black heat shrink to fit around one end of the LED and the other end of the light pipe. This should help to focus the beam of the LED into the light pipe; thereby giving you more light through the headlight. It's worth a try...
It is a plastic light pipe.
The LED itself seems to be dim. I don't know how to change it. The lights and the ditch lights don't light up very bright.
On the NCE PowerCab, I pressed PROG/ESC and then ENTER. I then pressed ENTER when it said PROGRAMMING ON MAIN. I pressed 2 for programming a CV, entered 117 for CV117, entered 2 for rule 17 (which supposedly cycles between off, bright, and dim), and when I press F0 (or 0 on the PowerCab throttle), the headlights still just turn on and off. I want them to cycle, and get brighter.
The ditch lights are probably fed with fiber optics, or more accurately a plastic light pipe - if the ends of this in the shell don't line up with the LED exactly it will also be dim - if the headlight itself is bright enough you may need to gently adjust things slightly to get better alignment. Don't snap off any more parts.
That info should be included with your MRC decoder manual.
I bought ANOTHER (the third) sound decoder from MRC, because I snapped off a resistor to the second one. I'll snap a pic of the resistor I need, if anyone knows what value it is or where I can find it.
I also used electrical tape as an insulator, and not a much thicker Gorilla tape, which has a higher surface resistance. This time the board slide right in (because of the lower surface resistivity of the electrical tape).
Apparently, the MRC board supports having the headlight on, off, Rule 17 (whatever that is), and bright. How do I program the front LED to be brighter using the NCE PowerCab system? The light barely shows to the ditch lights.
Sweet! And we all "woo-hoo" with you, gatrhumpy!
And please elaborate on how you finally arrived at that point. Thanks.
Round 2 a success! I now have sound! Woohoooo!
How is the store supposed to know that the decoader is defective. Did you have them test it for you? If not then it is not their fault. Like the rest of use you will have to deal with the manufacture.
I just installed a non sound Digitrax decoder in a Kato N scale SD40 and I only loosened the frame screws just enough to slide the dc board out and slide the new board in. That was all that was needed. Atlas engines are a lot more work I have never used the tape that comes with the decoders to isolate anything on any of my Atlas or Kato engines.
Of course this is my story, others may have different experiences.
Ken G Price My N-Scale Layout
Digitrax Super Empire Builder Radio System. South Valley Texas Railroad. SVTRR
N-Scale out west. 1996-1998 or so! UP, SP, Missouri Pacific, C&NW.
That would be you problem then. You should be able to get it replaced under warranty.
I did send you a PM.
But if the decoder is broken and you see parts missing, other than replacing the decoder there would not be much that I could do.
This is if the decoder is broken as you said in your last post.
Jerry
Randy, I followed the directions per the MRC decoder exactly.
I will place a small amount of solder on those two contact points just in front of the large square black chip.
I did make sure that the thin motor contact points were touching the wider copper contact points that go to the decoder.
And yes, the motor clips are contacting where they should - the top of the decoder in the center.
And I just figured out something. I was checking the structural integrity of the board itself, and there is a slight brake just in front of the large, black chip, in the board. There is a contact resistor that says '152' (I assume for 1.5K ohms of resistance) that is missing. It is the size of a pen point, no larger.
I did not bend the board and was very careful to not do anything to damage it, but something definitely DID happen to the board. At least I now know why it did not work in the first place. The very thin top and bottom copper lines on the board may have been breached and would hence not conduct electricity.
I'm extremely disappointed in the store selling me something that is defective. I plan to file something with my bank very soon. In the meantime, can I send the board to MRC for a new board? Heck, I have an electrical engineer that said he could solder the connections back together, and even has the same type of resistor in his shop that he could solder back to the board.
Well, that's very kind of you. I may take you up on that offer. Send me a PM, and I'll try to send you the decoder.
Start simple is the best advice. However:
Do NOT cut the skinny motor tabs. The skinny motor tabs are touched by the wide tabs that get attached to the decoder to get power to the motor. The two tabs should touch,. If you taped too far over the space above the motor the tabs might not contact, this will cause a failur in operation.
The decoder gets power through the frame halves where it slips under just iin front of the large square chip - there are pads on the decoder that should be touching the frame at that spot. This is usully where there is a problem, it seems some production runs of the Kato locos have wider slots than others, so the board fits loosely and doesn't make proper contact.
Also, when you took it apart, did you leave out either of the two thing contact strips that go over the trucks and under the top edge of the fuel tank? This is how power gets from the truck pickups to the frame halves. Without these, no worky either.
MRC has you insulate more areas of the frame because the sound decoder has components in those additional areas in front of and behind the motor that most standard motor decoders do not. Pressure down on the shell could cuase those components to contact the frame. This the extra tape.
Are the moto clips contacting ONLY the spots on the circuit board that they are supposed to? Slide them back or front a bit and they could short out other traces.
Or start with a simple (and far cheaper) "non-sound" decoder install first before jumping into sound. This will give you a chance to familiarize yourself with and learn about DCC and programming. Although sound is fun and does enhance the MRRing experience, it's not the reason I chose DCC.
gatrhumpy, take a nice, deep breath.............and slowly bre-e-e-e-athe out. DCC IS fun!
Well I can understand your frustration. You may not have a bad decoder- might be a contact issue- If it is a bad decoder, send it back to the manufacture. MRC's warranty is very good. The decoders are not that well thought of but I know they do support there product. Forget the retailer, He can't help you too much. I think that you would love the DCC and once you get over this hump you would be happy. I will make you a deal- send me your loco and the decoder-(with a proof of purchase). I will install- and test- if I find the decoder to be bad, I will send it to MRC for replacement- that is why I would need the proof of purchase. The only thing that I would ask of you is to pay for the freight (shipping cost) I feel this strong about DCC! I will invest my time to save you and have you a DCC fan.
Well I can understand your frustration.
You may not have a bad decoder- might be a contact issue- If it is a bad decoder, send it back to the manufacture. MRC's warranty is very good. The decoders are not that well thought of but I know they do support there product. Forget the retailer, He can't help you too much.
I think that you would love the DCC and once you get over this hump you would be happy.
I will make you a deal- send me your loco and the decoder-(with a proof of purchase). I will install- and test- if I find the decoder to be bad, I will send it to MRC for replacement- that is why I would need the proof of purchase.
The only thing that I would ask of you is to pay for the freight (shipping cost)
I feel this strong about DCC! I will invest my time to save you and have you a DCC fan.