What are these electronic components found inside a Schaffer BV 223-5-04008 PSU for the Commodore 128D?

Question

I'm having a little hard time trying to map some electronic components in a C128D power supply unit. The PSU is the Schaffer BV 223-5-04008 (schematic) provided with the German version of Commodore 128D. The board has no annotation and there are some mixed components from two different manufacturers that I cannot recognize or found for reference. In particular I am not able to found information about the one in this image:

Does anybody have information about this maker?

The complete board is here below:

Components I can't identify are made by Schaffer (the blue box up in the picture) and the green ones (except for the obvious ones like the resistors near the IC).

This is the back of the board (image not mirrored):

Schematic:
_{Source: Bo Zimmerman}

Additional pictures that could help:

Answer 1

The green caps marked F1772-410 are Class X1 type safety mains filter caps, rated 100nF and 440VAC, C1 and C4 in the schematic.

The green caps marked F1710-222 are Class Y2 type safety mains filter caps, rated 2.2nF and 300VAC, C2 and C3 in the schematic.

Based on these ROE and ERO logos, these capacitors are made by Roederstein, now part of Vishay.

The blue box that reads Schaffer 282/131 must be the pulse transformer TR2 in the schematic.

Answer 2

Components I can't identify are ... the green ones (except for the obvious ones like the resistors near the IC).

All of the boxy green components are capacitors. The ones at the left (mains voltage) side are class X and Y safety caps as detailed in @Justme's answer. The (visible) ones near the IC are marked .22K which is 0.22µF ±10% (K = 10%) and .47K63 which is 0.47µF ±10% 63V. The small green component below and to the left of the latter is a ceramic cap (C101? It's between R101 and the blue wire marked frei on the schematic).

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Other things of note:

• The loop of wire at the bottom-right (next to the red wires) is R124 and is a low-value resistor. The white ceramic block above it is R129, another low-value resistor. Both should be able to pass a significant amount of current.

• The grey orbs each with one black end are diodes as are the three-pin (TO-220?) parts screwed to the large heatsink (D102 and D103) amongst other places.

• The blue cylindrical axial components with a black band at the end (two to the right of the IC and one to the left of it by the variable resistor) are Zener diodes¹. The one with visible printing (4•7) is probably 4.7V (it's DZ101 on the schematic). As with all diodes, the black band marks the cathode. Zeners, however, are designed to have precise² reverse breakdown voltages and so are almost always used in a reverse-biased configuration with the cathode on positive side and anode on the negative (the opposite from how diodes are usually used)³.

• The wire colors at the right of the board/schematic are:

  • ge = gelb = yellow
  • rt = rot = red
  • sw = schwarz = black
  • or = orange = orange

• The DIP-14 IC appears to be an LM2901 quad comparitor (or a similar chip).

Board with components labeled	Traces and symbolic components (top view)

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¹ Thanks to @Justme for correcting me on that.

² Well, fairly precise. The breakdown voltage is current-dependent (the knee current) and lower-voltage ones tend to have a less pronounced knee than higher-voltage ones. This becomes most apparent with Zeners rated less than around 5V or so. See here for a more detailed discussion.

³ In a pinch, Zener diodes can be used as normal diodes (with about 0.7V forward voltages) provided one takes the reverse-biased characteristics into account.