Help with LGB Decoder madness

DGE-Railroad

DGE-Railroad

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I'm really helping someone can help me understand how I need to progress this. I'm stumped!

I have an LGB Mikado that has the Direct Decoder sticker underneath - from my research that means it should suit an LGB 55020/55021 or a Massoth L decoder daughterboard which plugs into the main board at the front of the loco..
directdecoder.jpg

The internal boards on my loco are as shown in the picture (the ribbon-cable type that hooks the small distribution board (center of picture) to the mainboard (shown at the bottom)) so it's not decoder-equipped at the moment as I understand it.
mainboard.jpeg

But... when I look at pictures of the decoders mentioned, above the pins do not look as though they'd match up? I'm at a complete loss. Is anyone able to confirm with a photo or part number, what decoder I need for this board?If I can't figure it out, I think my only option is going to be to rip everything out and start with bare wires to a 3rd party decoder instead. Does anyone agree?

Appreciate any help anyone can give!
 
ebay mike

ebay mike

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I'm really helping someone can help me understand how I need to progress this. I'm stumped!

I have an LGB Mikado that has the Direct Decoder sticker underneath - from my research that means it should suit an LGB 55020/55021 or a Massoth L decoder daughterboard which plugs into the main board at the front of the loco..
View attachment 261140
The internal boards on my loco are as shown in the picture (the ribbon-cable type that hooks the small distribution board (center of picture) to the mainboard (shown at the bottom)) so it's not decoder-equipped at the moment as I understand it.
View attachment 261141
But... when I look at pictures of the decoders mentioned, above the pins do not look as though they'd match up? I'm at a complete loss. Is anyone able to confirm with a photo or part number, what decoder I need for this board?If I can't figure it out, I think my only option is going to be to rip everything out and start with bare wires to a 3rd party decoder instead. Does anyone agree?

Appreciate any help anyone can give!
Hi. Both of those LGB decoders you have quoted are for small locos. I believe the current rating is something like 0.8amp. you'll need something which will handle a significantly larger loading. I've got three of the SNCF versions - all DCC, but don't have a clue what's inside. If I knew how to take one apart I'd have a look for you.
 
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penylanpip

penylanpip

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"I've got three of the SNCF versions..."

I still hate you, I want you to know! :envy:
 
DGE-Railroad

DGE-Railroad

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Hi. Both of those LGB decoders you have quoted are for small locos. I believe the current rating is something like 0.8amp. you'll need something which will handle a significantly larger loading. I've got three of the SNCF versions - all DCC, but don't have a clue what's inside. If I knew how to take one apart I'd have a look for you.
Thanks for the quick reply Mike. That was another thing that seemed strange - when I was looking up the part numbers, those decoders looked underpowered. I pulled the Direct Decoder information off Greg Elmassian's site but that decoder correlation he makes must be a bit more LGB generic. I suspect the Mikado is an exception! :rolleyes:

Do the SNCF versions run sound then? I wasn't sure if they did. I guess the fact you're running them under DCC means they must have a decoder fitted.
Mine wasn't too difficult to take apart. I followed the instructions at Large Scale Central - Advanced Forum Detail Topic - LGB Mikado gets RCS battery R/C. if you really don't mind. It's a bit much to ask though, if you don't have a good reason to do it!
If any have the direct decoder symbol on the bottom (6 white dots in a black circle, with the words 'direct decoder' around the outside), I suspect they'd be a good comparison though.
 
DGE-Railroad

DGE-Railroad

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I think you can use this LGB 55026 cable to plug into the small board, and then connect one of the 6 pin decoders.
Hmm. I'm not sure where on the distribution board that'd plug though Greg. My distribution board is fully populated.
distro.jpeg

I guess it'd replace the ribbon cable? That's taking the wiring to and from the mainboard - a continuity test showed me that with the loco switch in the 1 position, there's no direct connectivity between the pickup leads and the motor harness - everything goes through that main ribbon cable
 
muns

muns

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That board has the correct "sockets" to take an LGB 55020/55021 or a Massoth L decoder.

I believe there is only one motor in these locos and I suspect that the sound board and other electronics will take their power direct from the track.

If you wish to use a different (i.e. a more powerful decoder) then I can supply an adapter board that will plug into the existing board.


Oh...the 6pin cable Greg mentions is not needed.
 
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DGE-Railroad

DGE-Railroad

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Ah-ha. Figured it out with the assistance of a US contact. A Massoth emotion L will do the job, it's just that not all of the pins plug into the main board. Some aren't used. Doh!
I'll order a Massoth and try that...
 
PhilP

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I think you can use this LGB 55026 cable to plug into the small board, and then connect one of the 6 pin decoders.
NO!

You plug a 55021 into the big board, using the wires hanging off the end for pickup/motor No.1
Then you stuff a second 55021 'somewhere' just to drive the second motor-block..

T'was early-days of LGB DCC and to quote the Chitty-Chitty-Bang-Bang song: "I think we'd better think it out again!"

<Now having read Mark's post, and having to collect SW (no time to check) am not sure about the second motor?>
 
DGE-Railroad

DGE-Railroad

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That board has the correct "sockets" to take an LGB 55020/55021 or a Massoth L decoder.

I believe there is only one motor in these locos and I suspect that the sound board and other electronics will take their power direct from the track.

If you wish to use a different (i.e. a more powerful decoder) then I can supply an adapter board that will plug into the existing board.


Oh...the 6pin cable Greg mentions is not needed.
Thanks so much Muns. I *think* I'm okay. If it doesn't work out though, I'll be in touch for an adaptor as I'll go the 3rd party route
 
DGE-Railroad

DGE-Railroad

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NO!

You plug a 55021 into the big board, using the wires hanging off the end for pickup/motor No.1
Then you stuff a second 55021 'somewhere' just to drive the second motor-block..

T'was early-days of LGB DCC and to quote the Chitty-Chitty-Bang-Bang song: "I think we'd better think it out again!"

<Now having read Mark's post, and having to collect SW (no time to check) am not sure about the second motor?>
Thanks Phil.

Yep that's the conclusion Id arrived at. No second motor block on this one. (I'm not sure if the later revisions had though or whether that's a Mallet-ism..)
 
Greg Elmassian

Greg Elmassian

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I get it now... the first picture posted showed empty sockets on the distribution board, but those had the motors.

Now I see the pins on the main board that the decoder can connect to (original/early 55020 shown)



Greg
 
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ebay mike

ebay mike

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"I've got three of the SNCF versions..."

I still hate you, I want you to know! :envy:
But I need them for all those Pullman coaches, so there's no need to take the hump.
 
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ebay mike

ebay mike

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Thanks for the quick reply Mike. That was another thing that seemed strange - when I was looking up the part numbers, those decoders looked underpowered. I pulled the Direct Decoder information off Greg Elmassian's site but that decoder correlation he makes must be a bit more LGB generic. I suspect the Mikado is an exception! :rolleyes:

Do the SNCF versions run sound then? I wasn't sure if they did. I guess the fact you're running them under DCC means they must have a decoder fitted.
Mine wasn't too difficult to take apart. I followed the instructions at Large Scale Central - Advanced Forum Detail Topic - LGB Mikado gets RCS battery R/C. if you really don't mind. It's a bit much to ask though, if you don't have a good reason to do it!
If any have the direct decoder symbol on the bottom (6 white dots in a black circle, with the words 'direct decoder' around the outside), I suspect they'd be a good comparison though.
Yes. All three have sound, but each is differently equipped. Both of the 22871s were analogue as standard, but have been chipped. One has an LGB 65000 sound unit fitted, the other has a Phoenix soundcard installed. The 22872 has factory fitted sound and decoder. As you can see they're shoehorned into my pile of locos so may take a bit if digging to get them out to investigate.
IMG_20200127_194332.jpg
 
dunnyrail

dunnyrail

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What fun you must have digging out alol them boxes and having to then pull the Locomotives out of their boxes before you can put them on the track to run them. Is there any day left once you have done all that?
 
DGE-Railroad

DGE-Railroad

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Yes. All three have sound, but each is differently equipped. Both of the 22871s were analogue as standard, but have been chipped. One has an LGB 65000 sound unit fitted, the other has a Phoenix soundcard installed. The 22872 has factory fitted sound and decoder. As you can see they're shoehorned into my pile of locos so may take a bit if digging to get them out to investigate.
:cool::D thanks Mike. I think I'm fine now. But thanks for the offer, I really appreciate it
 
ebay mike

ebay mike

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What fun you must have digging out alol them boxes and having to then pull the Locomotives out of their boxes before you can put them on the track to run them. Is there any day left once you have done all that?
Not a lot Jon. In fact in the middle of that huge stack are boxes and sets that have never been opened.
 
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Dan

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I would not use the 55020 as these do not have Bemf and the Lenz version is very limited. The 55021 is a better choice and remember to set the 4 sliders to open as this disconnects the motor from track power.
And the 55021 is not a .8 amp unit as smoke units take up to 300ma to start heating up, and each bulb will take at least 53ma. Does not leave much for a motor if rating is .8 amps.
LGB rates the 55021 as a single motor decoder and the 55027 as a 2 motor but this is for LGB motors, not other manufacturer motors.
 
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DGE-Railroad

DGE-Railroad

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I would not use the 55020 as these do not have Bemf and the Lenz version is very limited. The 55021 is a better choice and remember to set the 4 sliders to open as this disconnects the motor from track power.
And the 55021 is not a .8 amp unit as smoke units take up to 300ma to start heating up, and each bulb will take at least 53ma. Does not leave much for a motor if rating is .8 amps.
LGB rates the 55021 as a single motor decoder and the 55027 as a 2 motor but this is for LGB motors, not other manufacturer motors.
Thanks a million Dan, that's really useful.
I had been meaning to ask if anyone had any information on what the mainboard switches do. I noted the 4 by the ribbon cable which I guess are the ones you're referring to here.
Do they just operate as
all 4 closed : motor connected to track power
all 4 open : motor disconnected from track power
:confused:

There is also a pair of switchers in the middle of the board near the big (capacitor?) bank. Any idea on those?