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About the Model Railroad

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The Randall Museum in San Francisco hosts a large HO-scale model model railroad. Created by the Golden Gate Model Railroad Club starting in 1961, the layout was donated to the Museum in 2015. Since then I have started automatizing trains running on the layout. I am also the model railroad maintainer. This blog describes various updates on the Randall project and I maintain a separate blog for all my electronics not directly related to Randall.

2022-05-12 - Another Update on the Branchline Automation

Category Randall

The Branchline has been running the Rapido Santa Fe RDC 191+192 for quite some time. Then it was 191 alone as the other engine stopped working. And then there were none. Then I programmed and tried the steam engine MoPac #153 2-8-0. Well that one didn’t last one day and although I fixed the original source of the derailment, I was still fairly skeptical of running a 2-8-0 on a tricky sub-par track like the Branchline.

Thus Jim suggested yet another engine & caboose from his extensive collection:

This one is an SP&S Alco RS-3 #4070, and it seems to be this Bowser model. I think it sounds and looks great.

As a bit of history, SP&S is the Spokane Portland & Seattle, which merged into Burlington Northern in 1970. #4070 is the post-merger number and that dates the model to 1970 or later.

I updated the programming script to run with #4070. Later I enabled lighting effect F5 for the cab gyro light, and a bit later I programmed the caboose directional lights to automatically match the engine’s direction.

I really like the result. Engine sound is great. The horn/bell are a bit muted and I might put that on the programming track to see if I can adjust their levels once I fix the broken NCE USB interface.

I also think the Alco RS-3 is a great engine for the Branchline. Prototypically these engines were great runners on short lines and their sub-par track. And in the model version, I find them also very stable on such model track. Plus everyone can agree that any Alco RS-3 looks fantastic with its beveled engine hood and cab.

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