I had a quick look again this afternoon so I could work out what caps to order.

The internal layout of the unit is very nice, as you might expect from the Germans. I thought this unit was from '87 however I think that may just be a service sticker, I found a printed label with 5/81 on it so potentially this unit is actually from 1981!

I've got the power distribution board figured out and it appears there are just three separate DC power circuits, each with its own full bridge rectifier.

To continue I need to find my solder sucker so I can start pulling caps and testing and replacing them. I intend to replace pretty much every electrolytic cap on the board, there's 20 or so in total not too bad at all.

From the good old days, when it was possible to replace components to repair equipment.

And if you want to know what it all does...

Did you get any manuals with your setup?

I have a digital copy of the bottom right manual (via the Bosch Classic website) but the manual for interpreting the scope waveforms I don't have and that is probably the most valuable to me as it's hard to guess that sort of knowledge.

9 days later

I picked up some parts from @timbo on Tuesday. Now I have two... one more and I believe I qualify for addiction counselling.

In related vintage workshop news, @VolvoHordz dropped off this spring tester that he picked up for me from Marketplace, and I've given it a quick tidy up and it appears to be working pretty well. My new KL Racing springs have a spec of 84kg @ 25mm spring height, and the machine here is showing 81kg. The machine might be off or the springs might not be exactly 84kg, or both. Next time I see my machinist I will bring the spring and compare what his tester says.

What range of sizes of springs can this thing test? Suspension springs as well as valve springs?

    Nothing as big as suspension. Any spring up to about 100mm tall and 50mm diameter at a guesstimate.

    Repco have just released some merch for Bathurst featuring that early retro logo. There's a cap and some t shirts that look kinda cool

    Major Ledfoot

    What range of sizes of springs can this thing test? Suspension springs as well as valve springs?

    It's just a basic old school valve spring tester. Handy for the reason James is using it for.

      8 days later

      Okay I have finally ordered a full set of replacement caps, 61 caps in total. I have where possible gone for Wurth Elektronik and EPCOS caps because I would feel bad about replacing all these nice German-made capacitors with something second-rate.

        jamesinc

        Okay I have finally ordered a full set of replacement caps, 61 caps in total. I have where possible gone for Wurth Elektronik and EPCOS caps because I would feel bad about replacing all these nice German-made capacitors with something second-rate.

        Korean and jap made are frequently better made than European

          8 days later

          Now I have two... one more and I believe I qualify for addiction counselling.

          ?

          Uhhhhhhhh so today I bought all this stuff for $50. The top looks to just be an oscilloscope, middle layer is a more modern motor tester (90s?), which has a lot of serial ports on the back, and also there's some kind of memory card slot or something on the front. The presence of a keypad makes me think this one will probably have some kind of software on it, note it also lacks an X/Y joystick so to me that suggests the display will have a raster output which again suggests it will be some rudimentary digital computer.

          Bottom row left to right we have a printer that takes receipt paper and appears to connect to the unit above it, YET ANOTHER MOT-201, and an 007.001 vacuum/pressure tester.

          The vacuum/pressure tester is in pretty rough shape and the hose barbs are all broken off and the dials are seized. Still, it is essentially just some gauges and some valves so I will see if I can get it in working order.

          Everything else seems okay.

          Okay, more updates.

          I tore down the 007.01 vacuum and pressure tester, cleaned everything, fixed one of the gauges, and reassembled. The barbs on the front (under the ports A, B, C, D) were all snapped off. I found some stainless steel replacements in the right size so am just waiting on them. Otherwise the unit is working great, and the gauges agree with my other vac gauge. The internal pipes had a bunch of contaminants in them, I flushed it all out. The valves were sticking so I basically flooded them with WD40 and worked them until they came free, then I flushed out the WD40. Everything works nicely now.

          Very cool James! I love buying and fixing old tools aswell.

          Noticed your slight mods to your drill press, grab a treadmill motor when you see them in council pickup and build a variable controller for it

            hamsandwich

            Very cool James! I love buying and fixing old tools aswell.

            Noticed your slight mods to your drill press, grab a treadmill motor when you see them in council pickup and build a variable controller for it

            Brilliant!

              hamsandwich

              Very cool James! I love buying and fixing old tools aswell.

              Noticed your slight mods to your drill press, grab a treadmill motor when you see them in council pickup and build a variable controller for it

              Interesting idea!

                I got this Bosch MOT-401 working. This is just an oscilloscope, basically the left half of the MOT-201. This one is newer, the internals are much more sparse and the layout is more modern. I tested a bunch of resistors and caps and everything tested OK so I fired it up and it appears to work. I haven't hooked it up to a running motor yet.

                The silkscreen in front of the CRT was damaged so I took one from a spare unit (one that is only good for parts) and installed it. Win!

                Okay getting pretty close with this unit. Still having trouble with the ignition cut out function but got everything else working.

                ^ hooked up to an LH-2.4 240

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