HP-35 Power Supply Waveforms

[albertofenini]

Hi Cruff
this is very interesting, we are in the process of rebuilding a HP65 PSU
and we are having some difficulties in finding some replacements, like the toroid
Can you tell us what did you use ?
Also replacing the transistor is proving to be hard.
The 1854-0550 can be replaced with a 2N3904 or a more easy to find BC547 (reverse pin out)
The 1954-0094 however can be replaced with PN3646 which is very hard to get
Do you think we could use the RS-2021 transistors like you did ?
Thank you very much for help !