On Sunday, March 19, 2017 at 7:16:33 AM UTC-7, Cursitor Doom wrote:
On Sun, 19 Mar 2017 16:34:43 +1100, Sylvia Else wrote:

On 18/03/2017 8:27 PM, Sylvia Else wrote:
The smoke escaped from my old oscilloscope today. I've determined that
it came out of R740, to the bottom right of the circuit diagram.

https://www.dropbox.com/s/9053dnyr0izv88r/XAMP.PDF?dl=0

This is because T711 has shorted out.

Not very surprisingly I cannot source a replacement BF472, so I need to
find a substitute.


I would try a MJE350(pnp/300V/500ma/20w/TO-126/hFE=30-240). Anchor Electronics http://anchor-electronics.com/ wants US$0.95 each.