I spent several hours reprogramming a Roundhouse 4-4-0 that I was not too happy with. It only knew stop and go fast with lots of input required on the DT400 throttle. It was almost as if I was wearing the control knob off the device trying to lasso this little engine into compliance.
CV’s 2, 3 and 4 all were set at a value of 16 (Out of a max availible value of 32) these were the Start Voltage, Acceleration and Deceleration values.
The sounds were reduced to a minimum volume and some are still too loud.
Chuff Rate reduced slightly from default, Bell Rate modified also.
CV 124 sets linear speed chart, slow start time and fast start times at slow speeds. I chose to have it set at 2 for the quick increase in low speed starting.
Here is the video. I threw some boxcars onto the track and had at it with the engine. It did fairly well stalling occasionally showing me where I missed the spots with the Bright Boy.
At the end of the day, the engine is actually useable in a switching scenario where before it wasnt and much more compliant in starting and stopping without excessive throttle use. She will move on one click empty and probably hold about 2 to 3 clicks loaded as a minimum speed.
Maybe one day someone will make a full blown gold standard QSI equippted 4-4-0 with the RTC and other goodies loaded in and do it right. That will make me happy with the small steam. None of that budget decoder crap.
The lesson is you can do alot with CV’s even in the worst performers and turn it into a somewhat acceptable product. That is the power of DCC against Analog. In analog, I would have to tear this engine down, install a BIG can motor, little gears and smaller drivers and trade larger voltage for slower sp
This is the 2nd report I have seen of the MRC decoders used by Athearn/Roundhouse being extermely susceptible to DCC voltage drops. It appears that the 5% max drop “suggestion” (equals 0.7 volts max drop under full load) is almost a rule for these particular decoders.
The 4-4-0 got scrapped today and tidbits saved for the parts box.
The tender, wiring and lightbulb was saved for the 4-6-0 that needs one. It is probably the second time in 30 years I scrapped an engine.
The reason? It cogs on downgrades and locks up completely under a load. None of my other locomotives do that. Maybe I got the only one out of the factory that did that I dont know. But the deed is done, and good riddance.
A couple of fellows and I in a model railroad club were wondering about voltage drops. We did find a couple of feeders with defective solder joints and fixed them. I have a good running Roundhouse 4-4-0 but I was experiencing hesitations where other engines ran very well. I installed a 1000ufd keep alive capacitor in the smoke box which pretty well took care of the hesitation issue. I know some of the blocks need more feeders.
Only my Roundhouse has problems in three of the fourteen blocks.
I bought two new Roundhouse 2-6-0s DCC ready only. I am putting in my own decoders and speakers.
This fellow has done quite a lot with a Roundhouse 4-4-0 conversion.
Don’t feel like the Lone Ranger, I’ve had problems with mine. Since I operate a lot of vintage Ho equipment I’m using conventional 12 volt dc cab control, but non DDC performance is lousy. My engine bucks badly on down grades and slips excessively under light loads (four or five free rolling cars, 2% or less grades)
The problem appears to be in part that the traction tires are not thick enough or the grooves in the drivers are too deep for the tires to make consistant contact with the rails. I also suspect something , either the drivers or the tires are slightly out of round. There also is excessive play in the gear train which I think might be fixable with a NWSL regear. I’ve written to Athearn about these problems, but no action so far.
Maybe this needs a new thread, but I would like to hear other’s experiences, and/or possible fixes. If nothing else misery loves company.