Sony A77 and external flash

Hi,

Sorry I'm new to this forum but I have a question relating to old flashguns. I have for many years  used Minolta and then Sony cameras, as a result I have also acquired a range of flashguns. I have an old Vivitar 550FD, Auto Thyristor - minolta dedicated, that works fine with an A100 I have,  so I tried it on the A77 and again it works fine. However, this is only a bounce flash - no swivel, so I started to look at the other odd bounce and swivel flashes that I have. This includes and old Jessops 280ABZ that works fine with a pc lead on the Minolta 7 and 9 that I have. So i checked the a77 user manual that says that you can use an external flash with pc sync lead up to a voltage of 400 v. The Jessops flash is rated variously at 70- 260 v so is it useable on the a77, without causing any damage.

I haven't tried it on the A100 as the camera has no flash sync socket, but as stated above it works fine with the Minolta 7 and 9.

Many thanks for your thoughts.