Marantz 240 - bad transistor?

[ocdecio]

@sanjib Q520 - 2N4123 is NPN, 2N3906 is PNP - could you please confirm?

 

[sanjib]

I found few threads using these replacements in 250 and it worked. So, I think it should be fine. Here is the one
https://audiokarma.org/forums/index.php?threads/marantz-250-restoration.754075/

 

[sanjib]

@sanjib Q520 - 2N4123 is NPN, 2N3906 is PNP - could you please confirm?

you are right I edited the list.

 

[Steven Tate]

Doing some browsing, I came across this transistor sub list for the Marantz 250 -- for what it's worth.
file:///C:/Users/srtat/OneDrive/Pictures/Marantz%20250M%20Stereo%20Power%20Amplifier,%20a%20vintage%20Power%20amplifier%20of%20years%201976..html

 

[ocdecio]

Thank you @Steven Tate . One thing to keep in mind is that there are at least 2 versions of the board, one has a germanium diode the other doesn't. Also the newer ones the diff pair is already 2N5961 originally.