I recently acquired a number of Tektronix 7000 series oscilloscopes. Three 7844s (two with Option 78 - P11 phosphor) have already come back from the grave 
. Today was the turn of one of three 7854s. Power on to display a random number of LEDs and nothing much else. Power supplies are all there, so there is hope. Usual problem with these is the ROM boards, so replaced the ROMs with a new set burnt from ROM images taken by Penti Hakka.
Yes, there is is life left in this 'scope yet! Now displays "SELF TEST COMPLETE" and it will store a waveform 
. The second one I tried this trick with did display the SELF TEST COMPLETE message and also readouts, but all are distorted, so I will have to investigate the A29 Display Board to find out what is wrong with that one ...
Adios until then
