Linear PSU teardown

Got couple of these 30v/2A and one 30v/5A, so i figured lets take a peek inside and such :). They're linear, so they're BIG, compared to wattage. Panel meters are analog, nice! :).
Both voltage and current have coarse/fine settings, too bad not multi-turn pots, but they are way too expensive to use in these, low-grade PSU's. Power switch is very sturdy, maybe too much, but better that way. output sockets are high-power rated, 4mm banana types, with ability to accept cross-fitted wire. There are 3 terminals: +30v/gnd/-, so it seems this has floating ability too. Yep, DMM showed dead short from GND terminal to safety earth.

inside was, well, linear technology. Funny thought, smoothing caps were removed from one unit. Transformer is beefy one, with many output windings.
Adjustemtn pots seems to be wirewound-style, nice!. Other finding were couple PCB's, some cind of control/monitor units?. Couple components which i havent seen yet, at least much, like panted caps, strange case diodes, and classic '741 Opamp, in ''metal-can-case''. You maybe see in photos, the wiring is very nicely organized. Well, not the mains cord thought, pretty hazardous looking :D.
The power was adjusted by thermal-balanced TO-3 transistor-like components, PD1515, mounted on heatsink.
Smaller PSU weight about 7kgs's

Thanks for your time, comments welcome! :)