[AMRadio] Power Supply Question

[Byron Tatum]

Hello-
  This may be a little off-topic but I thought someone here on the list might be able to help me understand something. I was getting ready to restore a couple of Galaxy V Mk II transceivers and power supplies. I have one AC-35 supply and one AC-400 supply. The supplies are very similar and either will serve with the Galaxy V's (6HF5 finals). The AC-400 supply is rated slightly higher and is designed for the Galaxy V Mk III and GT-550 (6LB6's).
  The AC-35 supply is very conventional with a bridge rectifier for the 800 VDC High B+ and another bridge for the 300 VDC low B+, with the negative lead of each bridge going to ground.
  However, the AC-400 has the same two bridge rectifiers, except that the negative lead of the High B+and the negative lead of the filter capacitor string for the high B+ is connected to the positive lead (output) of the Low B+ bridge.
   Thanks anyone who can help me understand this.
                       Byron WA5THJ