Simplex 4208 Restoration Project

This week, I will be starting the very lengthy process of restoring my new 4208, and I figured I would create a thread to document the restoration process as I move along. It isn’t in particularly bad shape for its age, but it does need a good amount of work.

Basically my restoration project will be made up out of a few parts, or phases. The first phase will be cleaning the internal parts, or boards. This panel has 8 “boards” on the inside, each of which serving a different purpose. I’ll be starting with the coder board, which is the bottom most board inside the panel.

As you can see, this board needs a good amount of work. There is a lot of rust on this board (not sure why, as the cabinet nor any other boards have rust) that will have to be taken care of. To take care of the rusted screws and standoffs, I will be soaking them in rust remover.

The parts that are the most damaged on this board, however, are the code wheel, and the two relays. The code wheel will actually be swapped out, as I have a spare that is in much better condition.

These relays seem to be completely rusted out and corroded on the inside, so I will be replacing them. Luckily, I was able to find the exact relays on eBay, so I will be buying those at some point this week.

The individual who removed this panel had also apparently cut the wires going to the code motor, however, those should be relatively easy to fix. All I have to do is trace them (there is a +24V wire, a N/O wire and a C wire), solder them, and wrap them in heat shrink.

So, that is the first part of this very lengthy restoration process. There will be much, much more to come. I’m aiming to post more about the coder board later on in the week, all depending on what I can get done with it by then.


Damn, that seems like quite the project. I’m already impressed and wish you luck on this endeavor

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Absolutely is quite the project. Daunting, but fun. Much appreciated though.

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I think that coder board has been in a flood. You can see the water line on the side of the relay on the right. It makes sense of why it may have been removed. Be sure to check the other components on the board as they probably have some degree of corrosion from water too.

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All of the other boards are actually just fine. No corrosion or rust, just dirt. The cabinet is not rusted either, so I wouldn’t believe it was in a flood as none of the other parts/cabinet have been affected. So I am not entirely sure what happened to this coder board in particular. But everything else on the panel checks out fine.

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