Juddering loco,s. is it the chip ?

[ronnie thommo]

Hi Guys

 

I have noticed that some of my loco,s judder.

It is only slight, but it is noticeable when hauling rolling stock..

The most notable culprits are my Hornby 56's

Another thing I am noticing, is that when the loco,s are cranked down on the controller they halt abruptly down the sequence, finally stopping dead.

Very unprototypical.

 

Not all loco,s do this.

My Bachmann 37's don't do this at all, nor do my sound fitted loco,s, one of which is a Hornby 56

My Bachmann 57's are fine too

 

My track is always kept immaculately clean, as are loco wheels

The common denominator is the chips I use

I have always used Bachmann decoders in all my loco,so but I've got a feeling this may be the problem

 

Loco,s don't just stop dead or judder on their way round,and it's quite frustrating

 

Any ideas folks ?

 

Ronnie

[RFS]

It's a common problem with Bachmann decoders, as they have old firmware that was designed for locos with flywheels.

 

What you need to do is adjust CVs 54 and 55 until the issue is resolved.  Bachmann give recommended values for some of their locos here - http://www.Bachmann.co.uk/pdfs/decoder_settings.pdf - but you may have to experiment.

 

Another solution is to use a better quality decoder, such as the Lenz Standard+ which can be had from German box-shifters for much the same price as the Bachmann decoders, although that may have changed recently with the Brexit vote!

[34theletterbetweenB&D]

There's two principal components to look at.

 

Intrinsic capability of the mechanisms. While decoders can compensate for - and in some respects near completely mask - mechanism deficencies, it is necessary that these are completely eliminated if the best performance possible is to be obtained. If the OP's loco mechs are all centre motor with both bogies collecting current and driven designs, then a smooth drive should first be obtained from 'vanilla DC' (resistance controller or battery) before decoder fitting. Single bogie drives are not so refined, and often set a limit on what even the best decoder can cudgel out of them in the way of performance.

 

Decoder capability. Varies a lot. There are decoders on sale that degrade the mechanism performance from that which may be obtained from operation on 'vanilla DC'. Buy Lenz, Zimo, ESU, CTE to avoid this. Yet to find a centre motor drive that the Lenz Standard fails to produce a refined running result with, that's where 'the quality' starts for the least expense in my opinion. (I view DCC as a utility, want to spend as little as possible on it, consistent with obtaining fine performance.) 

 

The locos uniformly 'creep' in and out of motion smoothly, and maintain this smoothness progressing throughout the speed range, with consistent and stable speed matching available for MUing 'any with any' (Bach, Dapol, Heljan, Hornby, centre motor mechanisms). The operator does have to set up the CV's to obtain this, typically half an hour once the method is understood.

[ronnie thommo]

Cheers RFS, may upgrade to abetter chip on the problematic loco's

 

Nice reply 34

 

I'm sure you're right. I think

[Kelly]

Fitting a blank plate in place of the decoder (assuming it has a socket) before spending money on a new/better decoder, to rule out mechanism issues would seem a prudent move, and one I've done on a few occasions.