Function decoder not talking to the main decoder.

Nodrog1826

Nodrog1826

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Not sure if I have another dodgy function decoder, or it's something else.

My RhB Ge 4/4 has taken to erratic running, well not exactly running, more stopping, think it has taken lessons from a container ship, it takes a good twenty feet or so to stop, full tilt when the controller is turned to off. As well as failing to operate both of the couplers that are fitted on occasions.

Thinking the deceleration CV was out of kilter, tried to read it, but its X, so to were most of the others.

So I took it apart, to see if the wires were pinched, snapped etc, no problems found.

So just out of curiosity I disconnected the function decoder from its pickups, its not wired directly to the LGB chip, and hey presto (Other former supermarkets were available.) I could read and set the CVs, all is as it was when new, except two I had changed.

More important it stopped on a sixpence.

When I connected the function decoder to the track, its as you were folks.

Any suggestions folks?
 
What models / makes of decoders?
What does function decoder do?
Any connections between the two decoders via anything else in the loco?

Leading question:
Are either of these decoders Massoth, with firmware from the new WIKI, downloaded in (say) the last six weeks?
 
A note regarding programming or reading CVs in a multiple decoder setup:
You can't program a decoder when multiple decoders are connected by track power - this will cause conflicts between the decoders.
If one or more decoders are connected to the main decoder through SUSI, the extra decoders have their "own" CV range and can then be programmed without disconnecting any decoder(s).
 
Not necessarily true. Some decoders have a "Programming address", some have "Programming Locks". The correct setting of these will allow CVs to be programmed in multi-decoder setups.
 
Just for info, if it helps, it's a large onboard LGB decoder, connected to a LGB sound chip, all standard for the loco. The function chip is a Massoth, so I suppose its all Massoth kit as it were.

P1020154.JPG
 
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Does the sound keep going if you lift the loco off the track? - Long stopping could be a buffer on the soundcard, perhaps??

Erratic running does sound more like a pickup problem.. Check along each side that there is continuity between skates, and all wheels with brushes.. Clean back of wheels where brushes contact. Check brushes. clean tyres / flanges.. .. Check skates move freely, and clean rubbing surfaces..
 
Erratic running, maybe the wrong choice of wording, it's more erratic stopping, Has the stopping distance of an ocean tanker, and that is with six coaches in tow.

But the stopping cv value is 3 same as the starting one.

The only other thing of note is that sound function 1 (whistle) has a delay of a few seconds, but it has been so since new.

Its more of niggle I would like to get to the bottom of, might even resort to taking out the function chip and couplers.

Have one of Mark's coupling adapters, I can plug into the decoder, on the way, if I can prog, the function output to 16,
sure with this set up it only allows up to 8.

Might even wait until I can get one of those new plug in onboard decoders pending from Massoth.
 
Delay on the whistle might be an indicator the decoder is expecting serial commands for the functions, so it waits to see if any more command packets coming before it decides function 1 is what's been requested.
 
It is supposed to be set to parallel with 14 speed steps, well that is what the navigator display indicates.

When it starts from standing, the whistle triggers automatically, it's only when you request the whistle there is a delay.

Anyhow will pull it apart when the adaptor arrives and tweek the function decoder, and check function trigger and stopping CVs,
then see the way forward from there.
 
I guess the soundcard is being passed commands from the onboard decoder?? Think you will find the onboard decoder is set to serial, or more likely, serial and parallel..
 
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