The flashgun has something called a 'trigger voltage' - you can measure it when the gun is turned on by putting a voltmeter between the central pin on the flashgun shoe and the metal strip along the edge of the shoe. On modern flashguns this is usually less than 6 volts, but on some old guns it could be 200 volts or more, and this will fry the electronics in many cameras today.
The Vivitar 283 is especially variable with different generations having a voltage anywhere between 5V and 600V.
One way around the problem is to fire the flash remotely as a slave, rather than fitting it to the camera hotshoe where it could do lots of damage.
See
this for more details of trigger voltages on different flashguns.
Personally I'd go for a modern gun which I could safely connect to the hotshoe, but it's your call.
