>four is plenty !!! >> I have 1N5408 to replace the old ones. Is 4 per leg enough PIV rating of >> 4000 volts for this supply of should I go to 5 diodes per leg ?? Why all the excitement? To save a buck per leg? Go for 5, or maybe 6. A '1 kv' diode should only ever see, what, 400v? And the 1N5408 is the next level up. Why push it? Bill K2AME ~~~~~