replacement ion + thermocouple gauge controller

In an older post I showed my original hot filament ionization gauge controller and the abuse it took during shipping of my vacuum chamber setup. Despite the fact that the only likely damage preventing it from achieving operational status was most of the front panel switches and some broken LED leads, I decided to relegate it to spare parts duty, and instead purchased the same model with some different options for $60 shipped.

Despite it looking more modern than my original, it's actually from the same period. This one just had the -1 dark grey finish option specified. The most notable difference with this one is the inclusion of two additional needle gauges to the left. I mentioned in the previous ion gauge post that some of these controllers include circuitry to read thermocouple-type vacuum sensors, and in the case of this unit, it can read two of them, though I only have the need for one. So this unit covers all the bases I need for high vacuum measurements, and the rest of the range can be covered by a mechanical diaphragm gauge. There are a few options that my old unit has that this one doesn't: some process control related stuff. For example, I could set some pressure trigger points that would activate relays for the purpose of automating some tasks. Nothing I particularly care about. Because of that, this unit is missing some relays, but otherwise has all the necessary trim pots. However, the front panel doesn't have the requisite holes to get access to them. Jeez...

Not everything has been rosy with this unit, and I haven't even powered it on yet. When I first removed it from the box, it was further packaged in a few layers of Saran wrap, but I heard something rattling around inside. After peeling away the polyethylene plastic, I found that neither the top nor bottom lids were screwed on. Well, I was going to open it up anyway, so I guess that's.... convenient?

The thing that was rattling around, but had already been corrected before taking these photos was that the single relay on the right side PCB fell off its base somehow despite it having been secured with a tie wrap that was too tight to slip over for reuse (so what you see is a new one). Also, the ribbon cable towards the bottom that connects the two boards popped off. Easy fix, and luckily my old unit had a plastic retaining clip that keeps the connector secured. Lastly, my original unit had a small shield that covered the sensitive electrometer circuitry in the upper right hand corner. Strangely, I don't see any markings/scratches on the PCB around the hole where it should have been attached from any fastener hardware. It might never have had it. Still, I have a shield so I think I'll use it. Other than that, I have the necessary fasteners for both lids, and the missing fuse holder cap.

I did just notice that unlike this unit, my original one didn't have solder masks on the PCBs. So despite the fact that the manual I have very much covers this unit, I'd say that this one is definitely newer.

The one other thing I'm aware of that I need to address is the thermocouple sensor interface which is via the the left hand card edge connector at the rear. I found one on Digi-Key that I think is suitable, but I'll wait to purchase it until I have a few more things to add to the list. Then I'll need to come up with a design for a 3D printed housing to securely attach it to the controller.