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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.

2021-09-22 - Bridgeport Maintenance

Category Randall

Time for more maintenance. This time I adjusted the grade crossing light sensitivity with some room lights off, and it seemed to go better. In this case I had the fluorescent lights off, the single center spot on, and the side spots (by the walls) on medium.

More importantly we had an interesting case: a turnout malfunctioned on the Bridgeport lead track.

That seems innocuous except this somehow shorted the B450 block on the mainline (the one that leads to Bridgeport) on the Mountain Panel 2, and it also made blocks B330 and B360 seem occupied on the Mountain Panel 1 -- these two blocks are used by the automation and since the track appeared occupied the automated trains would not start. It did take me some time to figure all that out since I started in reverse (why the blocks seemed occupied) and I had to trace it back to the short on the other panel and then to the Bridgeport lead. I still don’t have a full explanation here. It just doesn’t quite make sense.

Anyhow, this is what I found on the Bridgeport lead:

What’s wrong with the point?

And no, there is no image distortion here -- that is clearly a slightly curved turnout.

After wondering how the heck I was going to fix that, I realized there was something odd with that point -- it’s held in place by little metallic tabs, which is what allows it to move around. Thus it was a mere issue of putting it back in place carefully:

I have no idea what this thing is. I had never seen turnouts like this, or at least I had never noticed. Others I have seen have a clear metal stamped round pivot joint. So now I’m curious and I’d like to know what brand / model that is, in case I need to replace it.

As I was poking around in Mountain Panel 2, I also fixed a broken solder connection -- the one that provides DCC to the blocks no less. Sometimes I wonder how this thing even works to begin with. Can you spot the broken wire in this picture? Hint: it’s a 12 AWG (or 10?) aka bit fat red wire. Took me a while to spot it. Let me point it out.

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