Digitizing 3 pin LGB Gearbox locos

[stevelewis]

I have succesfully fitted a decoder in my Vintage LGB ALCO Diesel loco, I used a different method than I originally intended

I hve posted a report on it in the DIGITAL COMPILATION THREAD should any one be interested.

 

[PaulRhB]

I've added Steve's text into this thread to make it easier for me to link directly from the complilation, thanks Steve.
Paul

RE DECODER FITING IN OLDER 3 WIRE SYSTEM GEARBOX LOCOS
I have completed installation of a Massoth XL decoder in my LGB QM ALCO Diesel loco.

I devised what I think is a simple method of overcoming the 'problem' of the common WHITE cable on one side of the gearboxes...........this cable both supplies picked up power to loco's ANALOGUE PCB and and is also the same connector for one side of the motor supply, so therefore in DCC mode this is a no go situation!!

This motor feed and pickup MUST be seperated!!

I achieved this quite simply!

I insulated with around 10mm of plastic tape the metal strip which connects electrically the skate & carbon wheel pickups on the gearbox side which has the SINGLE white cable. the small piece of insulation is positioned to isolate the PIN to which the single WHITE cable, so now the PIN only supplies power to the motor contact, and the white cable becomes a motor feed from the DECODER

I soldered a NEW lead to the BRASS skate holder on the G box, this lead now supplies track power to one decoder input,
(it is nescessary to drill a couple of small holes in the gearbox housing to route the NEW cable inside the loco to the decoder,)

So from then in its just normal hard wired decoder installation using the 3 original LGB cables and the NEW cable for decoder input and motor feed, remembering of course its a bogie loco so it all has to be done twice!!

Lghts all wired to decoder and original PCB removed, it all worked first time.

I forgot to take phots, but I will prob be doing another and will remeber to do so then!

 

[whatlep]

I've added Steve's text into this thread to make it easier for me to link directly from the complilation, thanks Steve.
Paul
(snip)
I insulated with around 10mm of plastic tape the metal strip which connects electrically the skate & carbon wheel pickups on the gearbox side which has the SINGLE white cable. the small piece of insulation is positioned to isolate the PIN to which the single WHITE cable, so now the PIN only supplies power to the motor contact, and the white cable becomes a motor feed from the DECODER
(snip)

A very nice variation on the theme Paul, not least because it avoids the usual method (which I've used so far) of soldering a wire onto the motor terminal and isolating that from the pin. Means replacing the motor remains a drop-in job. Good thinking!

 

[stevelewis]

Yes it was quite a simple thing to carry out, it avoided having to provide a 4th pin!

It is worth noting that the soldered connection for the NEW wire has to be made to the SKATE brass bracket as the connecting strips which link the pickup brushes & skate do not want to take solder!!

Silly me forgot to take photos but if I get a chance I will do so And I must admit to misrouting the lighting cable from the cab end of the loco into the main body and it was a devil of a job to reassemble the body until I realised what I had done!!

 

[adelmo]

Steve: Thanks for sharing your digital conversion notes!

I will be adding a ESU Loksound XL to my LGB Rio Grand Alco soon and look forward to your pictures.

Alan