The Galaxy AC-400 power supply is one of several power supplies that I have restored. It is the AC power supply for the Galaxy GT-550 transceiver, and it replaced AC-35 that was used with earlier Galaxy transceivers, as the power requirements increased with more powerful sweep tubes in the PA. It can be used with the Galaxy V, the Galaxy V Mk2 and the Galaxy V Mk3. I have a Mk2 (as well as parts spares from a Mk3 and a GT-550). I also have a second AC-400 that I have not yet refurbished. These power supplies have truly massive transformers. Unlike some other transceiver power supplies of the era, which have an "economy" low B+ scheme, the AC-400 has a separate secondary winding for the low B+. The AC-400 will fit inside the Galaxy V series speaker case.
For this unit, I replaced the four original 100uF 400 VDC electrolytics used for the +850 VDC and +350 VDC B+ voltages with upgrades, since I knew that the actual no load voltages of the high B+ was close to +900 VDC due to my AC line voltage of about 123 VAC. The replacements I selected are 120 uF and 450 VDC. The snap-in replacements are much smaller than the originals. Rather than "stuffing the cans of the originals, I decided to make a PC board that covers the four empty holes and provides for mounting the snap-in caps. That made it easy to connect the wiring for the stacked capacitors. I hand-drew the PC board and used toner transfer to create the foil. See the photos for the result. I also replaced all of the under-chassis electrolytics and all diodes, and all resistors with metal oxide film (along with one cement 5W 2 ohm wirewound).
Photos of the power supply are below. Click to enlarge.