Old LGB Uintah 21881 #50 - DCC conversion advice

AusrailQLD

AusrailQLD

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I've recent debate on whether to convert one of these LGB locomotive to have DCC and sound.
And I'm curious to know if anyone has used one of these Massoth decoders in the loco.
Massoth XLS-Onboard Sound Decoder.

8206000_800px.jpg


Is this a good decoder to use?
I like the fact that all I need to do is use the existing plugs of the Motors, and the 4 position on/off switch.

Usually I always do my research before asking silly question, but I'm stumped on a few things.
Most of the plugs I can understand what they do.
But I'm not sure where the following will go on the board

- The Smoke unit. (Is it possible to keep the original 5 volt unit?)
- Multi-purpose socket (the old round terminals on the back of the bunker)
- Fire box flicker. (I would like to add a fireglow if possible)

I'm not fully keen on installing a reed switch for the chuff.
What CVs do I need to program to make the sound be affected by voltage steps and not hall sensor?
 
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Do you mean a 20881? I can find the manual for the 20882, and it reports support for the 55020 (together with a 55030 motor booster). That's very old tech.

Can you post a picture of the decoder interface socket and other mainboards?

There are two ways to do this, each with their own issues.

Add a 3rd party decoder in the same way you would have added a 55020+55030+55026​

In this case, you'd use something like a Massoth eMotion XL in place of the above combo. Wire the decoder's function outputs to the mainboard and connect the motor outputs to both motors. Lights and smoke are driven at full track power because the mainboard has the necessary voltage conversions.

Drawback: you're limited to the 6 built-in sounds and need to use a command station that supports LGB "serial mode".

Replace existing sound functions with a 3rd party loco + sound decoder​

This is what the XLS gives you. You could do something really odd and wire the XLS in the same way as you wired the XL above, and then connect a 2nd speaker directly to the XLS. This would allow the default sounds & smoke to function and you can overlay with your own additional sounds.

The more common way is to disconnect the speaker from the mainboard and reconnect it to the XLS. The XLS is now entirely responsible for sounds.

For smoke & light, you have similar options. Firstly, you can leave the default connections via the mainboard. This works fine for lights, but for smoke you would still need to drive it via LGB "serial mode" - but only the smoke option (serial F3) does anything.

Alternatively, you can rewire the lights and smoke directly to the XLS. If you do this, you will need to set the voltage outputs on the functions to 5V (and/or add voltage regulators between the outputs and the 5V lights / smoke). Note that it should be possible to drive the lights via the mainboard and the smoke directly, if this works better for you.

I'm pretty sure the XLS can do "chuffs" for you, without needing reed switches.
 
Andrew_au said:
Do you mean a 20881? I can find the manual for the 20882, and it reports support for the 55020 (together with a 55030 motor booster). That's very old tech.

Can you post a picture of the decoder interface socket and other mainboards?

There are two ways to do this, each with their own issues.

Add a 3rd party decoder in the same way you would have added a 55020+55030+55026​

In this case, you'd use something like a Massoth eMotion XL in place of the above combo. Wire the decoder's function outputs to the mainboard and connect the motor outputs to both motors. Lights and smoke are driven at full track power because the mainboard has the necessary voltage conversions.

Drawback: you're limited to the 6 built-in sounds and need to use a command station that supports LGB "serial mode".

Replace existing sound functions with a 3rd party loco + sound decoder​

This is what the XLS gives you. You could do something really odd and wire the XLS in the same way as you wired the XL above, and then connect a 2nd speaker directly to the XLS. This would allow the default sounds & smoke to function and you can overlay with your own additional sounds.

The more common way is to disconnect the speaker from the mainboard and reconnect it to the XLS. The XLS is now entirely responsible for sounds.

For smoke & light, you have similar options. Firstly, you can leave the default connections via the mainboard. This works fine for lights, but for smoke you would still need to drive it via LGB "serial mode" - but only the smoke option (serial F3) does anything.

Alternatively, you can rewire the lights and smoke directly to the XLS. If you do this, you will need to set the voltage outputs on the functions to 5V (and/or add voltage regulators between the outputs and the 5V lights / smoke). Note that it should be possible to drive the lights via the mainboard and the smoke directly, if this works better for you.

I'm pretty sure the XLS can do "chuffs" for you, without needing reed switches.
Click to expand...
Well, I recently completed work on a customer's LGB 20882 Uintah with factory sound. The locomotive's User Guide indicates it has a DCC Interface connector and my customer only wanted me to convert it to DCC using that Interface with a Massoth XL Decoder. However, when I disassembled the locomotive (one of the worse to do because of all the tiny screws), I found there was no DCC Interface.........the User Guide was in error. I checked with a hobbyist friend of mine who also converted his 20882 to DCC and his too had no Interface. So, the option was to remove the main circuit board and replace it with the XL Decoder and retain the old analog sound board. The other option was to remove both boards and replace it with either a Massoth XLS DCC sound decoder or an ESU LokSound 5XL DCC sound decoder. My customer likes the sound of the old sound board so I retained it and installed the XL for the lights, smoker and power to the sound board. I had to install two ESU miniature relays so the whistle and bell could be activated by F Keys on the DCC throttle. I have a demo video with photos also of the installation on my Website at: LGB LOCOMOTIVE DEMO VIDEOS | My Site

There's also a video on my Website's Homepage of an LGB Uintah, non-sound, that I converted last year to DCC sound using an ESU 5XL DCC sound decoder. I normally remove all the factory electronics in an LGB locomotive that I convert, even if it has a DCC Interface. The latest DCC Sound Decoders are far superior than retaining the factory sounds, and the using a DCC Interface can be a potential failure down the pike anyway which will then require doing a new DCC sound installation. My Website Homepage: LGB Trains | Old Dominion Railways | Repairs & DCC Installs | United States

Now for some commentary between using the Massoth Uintah sound file v. an ESU American steam locomotive sound file (there is no Uintah at this time). First, the ESU 5XL is a much more complex decoder that produces outstanding sounds and locomotive operation........just watch the video on my Website. I also like the Massoth XLS sound decoders but the Uintah, the Mogul and the Mikado sound files have some chuff distortion in the low speed step range. I've complained to Massoth several times to fix it but last time I checked, they are not fixed. So, for the Uintah, I'd definitely go with the ESU 5XL decoder. But to set it up, you need the ESU LokProgrammer or find an ESU Dealer like myself who will set it up for the customer, all the voltage settings for the lights and smoker, not just install the sound file. The ESU sound file I used in the customer's Uintah on my Website is the American SooLine 1003 2-8-2 Steamer Sound File #S0574. All the ESU sound files can be found on the ESU Website Downloads page.

By the way, if you'd like the easier Massoth XLS decoder to set up, you could use a different American steamer sound file than the defective Uintah file. I've loaded the Massoth US Steam Locomotive K27/K28 sound file on an XLS decoder a customer was buying from me recently, and found it did not have the chuff distortion like the Uintah file has.

If you have any questions, you can reply to my posting, or you can email me at: olddominionrailways@gmail.com
 
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Sorry for some reason I typed the wrong ID code.
The LGB loco is #21881 #50 Uintah
It doesn't come with sound, or a DCC interface of sorts.

I just though because it has a 4 pin plugs to the circuit board. This DCC decoder below might be usable.
As it looks like I could simply plug the original motors and '4 position switch' plugs into the provides ports.
8206000_800px.jpg
 
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Andrew_au said:
In place of the track relay contacts? Why did you need relays rather than direct connection to the F outputs?
Click to expand...
You don't..
Both are switching a ground connection, but I can understand why a commercial installer might do this.

If there is a difference in the negative 'ground' potentials, between the two boards, then you can get current flowing between the two which could destroy the electronics.

PhilP.
 
Right the decoder supplies a path to ground when the function is activated.

If the sound board wants high (plus voltage) for activation, you have to invert the logic. This is done simply with a transistor, but many installers are more "electricians" than "electronics engineer".

So making the decoder trip the relay, and the relay switch positive to the sound board is easier for many people.

Greg
 
AusrailQLD said:
Sorry for some reason I typed the wrong ID code.
The LGB loco is #21881 #50 Uintah
It doesn't come with sound, or a DCC interface of sorts.

I just though because it has a 4 pin plugs to the circuit board. This DCC decoder below might be usable.
As it looks like I could simply plug the original motors and '4 position switch' plugs into the provides ports.
8206000_800px.jpg
Click to expand...
I've attached a photo of the LGB 20882 Uintah Main Board I removed to install the Massoth XL Driving Decoder.......your LGB 21881 Uintah uses the same Main Board. You'll note that you'll only be able to use the two motor block cable connectors into that Massoth XLS Onboard sound decoder. All the other factory installed cables/plugs you'll need to cut off and solder on the Massoth 2-pin or 3-pin min connectors with cables in order to use the XLS Onboard decoder. You also can't use the factory installed Power On/Off Switch with cable/connector. I'd recommend you use the regular Massoth XLS with screw terminals. Those XLS Onboard decoders are made to be used with newer LGB locomotives with the mini-connector plug/cables.
LGB 20882 Uintah Main Board.jpg
 
First board shown has 3 large 4 pin connectors. 2 are for the motor blocks and the third is for the switch usually located in the firebox. One end of the board is rear light control and the other end is front light control. What is missing is a 4th red 4 pin connector for a SUSI bus LGB used for connection their sound unit. Other smaller board shown looks to be a 5 volt power output conversion board. When I converted the Unitah to DCC I used the all-in-one Zimo MX699 which has too many features to mention here.
 
Dan said:
First board shown has 3 large 4 pin connectors. 2 are for the motor blocks and the third is for the switch usually located in the firebox. One end of the board is rear light control and the other end is front light control. What is missing is a 4th red 4 pin connector for a SUSI bus LGB used for connection their sound unit. Other smaller board shown looks to be a 5 volt power output conversion board. When I converted the Unitah to DCC I used the all-in-one Zimo MX699 which has too many features to mention here.
Click to expand...
Dan, the advantages of using the Massoth XLS Onboard decoder v. the Massoth XLS Screw Terminal decoder is probably a wash. The Uintah board's existing two motor block connectors and the power switch connector can be connected to the XLS Onboard decoder, although on DCC the Power Mode Switch isn't normally needed. The locomotive's smoke push pin connectors can be connected to the Onboard decoder's smoke pins. The headlight and cab light wires will need to be soldered to Massoth mini connector plugs. And the Uintah sound board that I worked on had no SUSI connector............the two red wires shown in my photo above power the sound board. I connected the sound board to one of the Massoth XL decoder's terminals and dimmed the voltage down to 11 volts.
 
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