Do you mean that it has except from the front and rear lights power outputs for aux1 to aux4 or aux1 to aux6?

Hello John, the Forum Luddite here,

I have only recently started to upgrade old locos with new decoders, and I am assuming that once this plate is installed and wired, you can insert any 21 pin decoder to the plate, or does it have to be an ESU decoder?

I have read quite a few of your conversions, but not sure if I can recall what part you use for the firebox light?

Looking forward to seeing the pictures

BR

Tom, when you say recent Loksound V4.0 decoders, are you suggesting earlier sound decoder V 4.0 are not in this category (Aux 5 & 6) ? is it not possible to update the decoder firmware ?

John

John,
I don't work for ESU.
In the latest manual they give different specs for "v41" and "v43" decoders. Maybe there is such a mark on the decoder, I didn't check that yet.

Does not look like a software issue, I think there are hardware changes.

Bart, here is a documentation of the adapter board (2) 51968 although the picture and instruction manual shows the older type, I don't know where Tom got it from

I don't think the 2 amplified outputs have changed.

here is the front side



John

Yes, it has changed.
Looks like 2 double transistors (6 connections each), indicating 4 amplifiers, while the original 51968 had only 1 of those double transistors.

This is supported by the newest Loksound manual (May, 2016 version), which contains this table:
LokSound V4.0
LSV41 21MTC: 4/250 mA + 2 Logik
LSV41 PluX / Kabelbaum: 6/250mA
LSV43 21MTC: 4/250 mA + 4 Logik
LSV43 PluX / Kabelbaum: 8/250mA
LokSound V4.0 M4: 6/250mA

Assuming that LSV41/43 indicate different versions 4.1 and 4.3, the v4.3 Loksound 4 21MTC was enhanced to have 2 additional unamplified ("Logik") outputs (now AUX 3/4/5/6 as compared to AUX 3/4 in v4.1).
This would be in agreement with the 4 amplifiers on the new 51968 board.

Surprisingly, if the table is correct, the M4 version is now suggested to have amplified AUX 1 thru 4 ("6/250mA"), which I find somewhat hard to believe. That would render it compatible with Märklin boards but incompatible with the 51968 board, which wants to see unamplified AUX3/4 inputs.

There is no updated LokPilot 4 manual online, so we will wait and see whether the 21MTC LokPilots are being updated as well to have AUX5/6 available (and whether the M4 versions now will have amplified AUX3/4 to make them fully Märklin compatible).

Interestingly, the older PluX22 LokPilot 4 M4 already had 9 amplified outputs, so neither costs nor space were a limitation to add output transistors on the decoder board itself; it is just the 21MTC protocol that limits the number of outputs.

Yes, it appears that not all paragraphs in the manual were updated to accommodate the v43 changes.
You are probably right that the table on page 8 I referred to (suggesting Mä compatibility of the M4) is incorrect and the table on page 58 is correct.
It would be hard to believe if ESU now would give up NEM660 in favor of Märklin's standard.

The difference between LokSound 3 and LokSound 3.5 was just firmware - you can use the LokProgrammer to upgrade a decoder from LokSound 3 to LokSound 3.5.

But IMHO a firmware upgrade won't be enough to upgrade a LokSound 4 decoder from 6 outputs to 8 outputs.
I take it for granted that "v41" and "v43" refer to hardware versions. I still didn't check if a small "v41" can be seen on the decoder PCB.

I assume they added more outputs for the PluX22 socket and now also make most of them also available for the 21MTC socket.