I wholeheartedly agree, colin. :thumb: Especially older locos that are not "all wheel pickup". With older locos such as these, I've found DCC to be reasonably tolerant once the loco is on the move. It also makes it a lot easier to find those niggly spots. With DCC you can run with the headlight fully on, at slow speed, and headlight flicker is a good indication of grubby track etc, when moving along at slow speed. With DC, the headlight would glow relative to the speed. slow speed, little glow, so that headlight flicker was hard to determine.
DC, with grubby track, you didn't really know if the motor was getting power or not. With DCC, if the headlight is on, then power is available, and older motors etc can be "fine tuned" to get a much better slow running, with the use of "start voltage", and "kick rate" and "kick depth" of DCC decoders.
But this is all not to say the older DC locos are not just as sensitive to dirty track, when run on DC, as when converted to DCC, of course.
Momentum, at speed, on DC with dirty track was usually enough to kick it along to the next bit of track pickup, even though that produced a jerky operation. With DCC, if the loss of power is too long, then it will stop, and then rebuild up to what speed step it was at, especially of you have used the "acceleration" CV.
I'm yet to muck around with the "packet dropout timer CV" to lengthen the time before the decoder sets itself to speedstep zero, when a loss of power/DCC data packets is detected.
I'm still very new to DCC, but I think the default for my DCC booster is "??continuous resend??", where it repeats the DCC commands that are current for all locos at regular intervals. (I think it's doing that).
With older locos, and dodgy pickups, when the loco hits a dodgy bit of track and loses power, the momentum, at speed, will shove it along to maybe pickup power again, but that short loss will be enough to reset the decoder to speed step zero.
If I understand the workings of DCC correctly, that is possibly what is happening on dodgy track and old pickups.
On my older locos like that, the loco comes to stop. (even though the headlight may remain on, the "momentum" of the loco will have shoved it along to a spot where the power pickup is OK). Then, due to the "DCC repeat mode" of the booster, off it goes again, as if you had set the speed etc via the cab controller. Especially noticable if you have used the "Acceleration" CV.
With my older non-all wheel pickup locos, it's a track clean just about every time I want to use them. DCC or DC. With my all-wheel pickup locos, I hardly ever have to clean the track, DCC or DC.
DCC really does make a good motor/mechanism/pickup run brilliantly compared to DC, however, to get and older motor/mechanism/pickup to run acceptably, compared to DC, takes quite a bit of fine turning, but it can be done.
With my older locos, I've had to set the "start voltage" pretty high (around 100) to get them to move off with a low speed step setting. With a "start voltage" of anything less, or zero, they wouldn't move off till I got to a speed-step of around 50 - 60. "kick rate" and "kick depth" seem to be only valid for speed steps below about 20. (on 128 speed steps).
Well, that was a lotta waffle, wasn't it. sign1 but I know what I meant.
