ZB "U" class 21711 - odd little problem..

RH Prague

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28 Oct 2009
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It's been a slow start to the season for me so this fault showed up on the loco's first run of the year. The lights (including in the cab) go on and off during running. It's been fitted with a Massoth LS chip, and after a while I realised that the lights go off/on strictly according to speed. i.e. with even number speed on the controller the lights come on, and go off on an odd number speed. The only exception to that rule is, they also don't come on on speed "0". Everything else seems to be pretty much normal both in the loco and on the controller. It is for example correctly set up for 28 speed steps. The smoke is temperamental, but it always has been.

Odd, huh? Does anyone have any thoughts?
 

PhilP

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This will be a speed step miss-match 99 times out of 100.

A case of checking CV29 in the decoder, and the value configured for this loco in the Cs..

PhilP
 
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Gizzy

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I concur....
 

RH Prague

Central European. the station pub is Czech !!
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Thanks, will check it out over the weekend.
 

RH Prague

Central European. the station pub is Czech !!
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Ah sorry guys, I thought I might have learnt enough to do this, but as a perennial beginner, especially with Massoth, I find that this was above my pay grade:cry:.Would one of you kind souls please walk me through what PhilP PhilP refers to above, step-by-step? First of all, does the loco need to be on the test track or can it be done on the main track?
Then on the Navigator, do I go to Decoder programming- CV Read+Prog - CV-Nr and enter 29? (hopefully yes) and then, what are the next steps please?

I thank you!
 

OBBherr

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Here are some notes I made for myself while learning to program with the Navigator. I much prfer the Service Tool now I have the PC Module but that's not without it's challenges either; albeit good for decoder programming.

My Navigator is not at the current firmware level so PhilP and Gizzy might want to check that the attached are still correct, or not.

Step Key Menu item

1 M3 M3 key for MENU

2 M1 Cursor moves down 1 step to Decoder Progr.

3 M2 OK Loco Address

4 M2 OK To select Loco Address sub-menu; cursor moves down to Address

5 M1 CV→ reads address, speed steps, direction and digital/analogue

6 M1 Goes to CV Read + Prog. Menu

7 M2 OK drops to CV number

Enter value of CV to be read

ALWAYS READ CURRENT CV FIRST!!

8 M2 OK OK to confirm; cursor moves to value

Either

9 M1 CV→ reads CV value

Or

10 Enter new value; shows binary equivalent below

11 M2 OK OK to confirm change; tick appears by new value if OK

12 M3 To exit back to driving mode

Hope this helps and apologies if anything is incorrect.
 
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RH Prague

Central European. the station pub is Czech !!
28 Oct 2009
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OBBherr OBBherr thank you, your notes above are perfect. Massoth really should pay you to write up a manual for customers who have not already learnt the hard way how to understand and interpret the gnomic word salads that they offer by way of "instructions".

Anyway...when I get to step 5 in your process, I think I already see the specific problem I'm trying to fix. It shows the speed steps here as 14, whereas it is 28 on the main driving screen. It is also showing 28 at step 3 on your process. However here at step 3, it also shows analog/dig as A.

So (EDIT) my next ask *was*, how do I go about changing these apparent anomalies?

However I FIXED it:), but in step 3, by changing the "analogue" to "digital there". I would have supposed that the 14 step thing in step 5 was the issue, given how it was behaving, but there we are.

Thanks again to all!
 
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OBBherr

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That seems to have confirmed PhilP and Gizzy's theory about speed step mismatch. Your decoder is set to 14 but your Navigator is set to 28.

So you can either:

A. Change the Nav to 14. Press and Hold M2 and the first screen you come to allow you to cyycle through 28, 128 and 14 by pressing up arrow (M2 again). Press OK repeatedly to cycle through other parameters inclusing name and icon till your asked to save. When you do that yo're back in driving mode
OR
B. Change the loco to 28, giving finer speed control. Now I'm not the expert on this as I use the service tool for programming. If you do too then it's fairly self evident what you need to do (and visual). If not then MY UNDERSTANDING (based on Stockers' Dummies Guide sticky at the haed of the DCC section) is that you need to change the slightly complex CV29. Looking at the sticky, it appears that you need to read the current value of CV29 and then add 2 and write that increased value back using steps 5 to 12 above.

Again I defer to other forum members if I've missed something.

Good luck and let us know how it goes.
 

wandgrudd

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OBBherr

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Your edit overlapped with my reply.

You are now ahead of me in the Massoth stakes, as I don't know what that A or D at step 3 actually does.

I'm assuming that A means Analogue + DCC and D is DCC only? I'll have to read the manual again. Anyway glad you're all fixed.