I followed your instructions and it worked. Thank you for the information. Not sure why this K-4 was a problem, my other Bachmann K-4 worked just fine with no adjustments.
I know....I installed a decoder in another Bachmann K-4 w/o a problem...this is the first one I've run into that had an issue. I would cut the caps suggested in the other posts but I want to make sure I'm cutting the right things. The link in one post shows a picture of a circuit board but it is different than the one in the K4
OK, I have a question.
I have four Spectrums, including the 4-8-2, and they all have D13SRP decoders, and I didn't cut the capacitors on any of them.
What's up with that?
Rich
Alton Junction
I have the same issue w/ a Bachmann Spectrum K-4. However; the circuit board looks different that the one on the web site you listed. Have you seen pictures of the K4 circuit board? I don't want to clip the wrong thing. Thank you
Rod
Thanks Randy,
It is starting to make sense now. Will play around with it and see what affect it has on the loco performance.
-Bob
Life is what happens while you are making other plans!
Start voltage is set to get the minimum starting speed on speed step 1 or 2. Easiest to use Ops Mode programming for this as well as CV5 and CV7.
CV5, max speed is set so that at the maximum speed step, the loco goes some reasonable speed - so a freight diesel doesn't go flying along at 200 scale mph.
Once you ahve that, CV6 for the mid is a matter of preference. Left alone, the speed will be linear between the start and top speed. For a mainline road loco, you might want to set CV6 to less than the mid point between CV2 and CV5 - so there will be a short ramp up and then lots of top end. For a switcher - just the revers, make CV6 somewhat higher than the mid point between CV2 and CV5 - thus there will be a large range of slower speed with a quicker jump at the top, light engine move from one side of the yard to the other.
That's for a single loco. For speed matching in consists, you have to adjust CV2 so both start at about the same speed - speeding up the slower one. For CV5, adjust the top speed of each, slowing down the faster one. Then adjust CV6 so that the mid point is close on both.
You can use a JMRI on-screen throttle and Ops Mode in JMRI, but really this is just as easy to just use the throttle, at least with my Digitrax throttle. I really only drop back to JMRI for more complex things, like adjusting function effects or sounds in sound decoders. Basic address and speed programming, it's just quicker for me to use the throttle than keep going back to the computer and making changes.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
The Digitrax decoders I have used are the DH123 and mostly the DH163/165 (I think the 165 in the newer version?). Neither have given me this kind of reaction to Bachmann PC boards.
As for the start/mid range/max voltages, how do I determine what to set them at? I am just not that familiar with some of the settings on DecoderPro.
Which Digitrax decoders were you using? All Digitrax decoders also have high frequency drive, could be the circuit design isn;t as affect by the Bachmann capacitors, but I've had to take them out for TCS decoders as well. If they were DH123 series, they were comparable to the NCE, if they were DH163/DH165 series, they have BEMF which the NCE doesn't, although it's not near as good as TCS's BEMF, but even more than the silent drive, BEMF is adversly affected by the caps
Bob, taking into consideration the type of work and design for the loco, you would want to set CV 5 near the upper range permitted for that CV for a passenger train, and maybe something less for a freight loco, but it really depends on the gearing and the power of the can motor.
Even though it is a higher CV number, CV6 is actually the MID-RANGE voltage, and you would want it set near the middle of the range of values for that CV...typically both have the same ranges. For most applications and locos, that works well, assuming the manufacturers haven't installed insane gearing one way or the other.
Crandell
It was the capacitors! I cut both and reinstalled the decoder (which was reset to default). I also checked CV2,5 and 6 and all were at 0. It runs better than it did on DC and I set the Accel and Decel to 8 and 4, which works OK. I don't know how to set start, mid and high voltages but it could use some adjustment here as it starts to move at speed step 4 and is not smooth, kind jerks into forward movement (buut still at a very slow speed). Should I mess with the start voltage?
I have quite a few Bachmann Spectrum locos (8-10) and only cut the caps on one of them. Never had this problem before, but most of them have Digitrax decoders in them. I just started using NCE a few months ago as I read (here on this forum!) that they were better at slow speed control than Digitrax.
Thanks to all of you again, I was ready to call NCE and send the decoder back! As I have said before, if it wasn't for this forum, I probably would still be on DC. You guys are livesavers. Thanks again (and again!).
Default for them in most decoders is all 0. If they are non-zero then they need to be in logical order, although most also interpet say CV5 lower then CV6 as CV5 being equal to CV6, so you will simply hit a speed plateau at mid throttle.
rrinkerTry resetting the decoder, and make sure CV2, 5, and 6 are all 0.
Randy,
For CV2, 5, and 6, I think you mean make sure they are in logical order? In other words, CV2 [start voltage] should be a low number, CV 5 [high voltage] should be the highest number (try entering 255 to see if that helps), and CV 6 should be in between the other two. In fact, sometimes having CV 6 too far towards low or high volts will lead to wonkiness in my experience.
If all 0, then it may not move?
For the OP, try reset for the decoder, which you've probably already done. Arcing, shorts and other noise in the signal can make even a new decoder act weird or give you other than default settings through no fault of your own. If the reset doesn't clear things and fiddling with CV 2, 5, and 6 doesn't either, then it might be a bad decoder.
Mike Lehman
Urbana, IL
And make sure that you have the decoder set to ignore DC.
Bob.
You must clip the capacitors from the Bachman boards. These caps will interfere with the motor functions big time. http://www.gatewaynmra.org/dcc/engines/bach-280.htm
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
Try resetting the decoder, and make sure CV2, 5, and 6 are all 0. And depending on address, make sure CV29 is set such that it is NOT using a speed table.
Also clip off the capacitors across the motor leads, they can and will interfere with the high frequency 'silent running' motor drive.
Lastly, since they are plug-in decoders, try a known good working one to rule out the decoder.
I just installed (plug-in type) an NCE D13SRP decoder in my new Spectrum 4-8-2 DCC ready engine. I plugged the 8 pin connector in and left the decoder at factory default settings. When I put it on the layout it ran in the correct direction (plug is in correct orientation) but wouldn't go very fast and then when I turned the throttle down to '0' in kept running. Finally had to shut power off and restart. It does the same thing in reverse. I then set the address to 43 and adjusted the accel and decel to 8 and 4 using DecoderPro, hoping this would fix it. Same thing and the loco would not even reach half speed and again would not stop. I finally removed the decoder and put it back on DC and it runs fine. I just got the decoder yesterday and have always had great results from the NCE decoders (most of my earlier decoder installs were Digitrax, which work quite well also) but am thinking the decoder is bad. Any suggestions? I even put the decoder on my NCE decoder tester and it seems to be OK, at least it read all the settings and let me reset to factory default, again using DecoderPro.