Phase linear 700b transistor replacements

[Slake]

Hello
I am a new member to this site and this is my first post. I have been collection and repairing vintage audio gear for 15 years.
Yesterday I purchased a non working Phase Linear 700b (Serial# 2555). I believe it is a series 1?. The current transistors are 2N3773’s Motorola’s as the main 20 transistors. I read in the phase Linear service manual that the 2N’s were not a good choice.
My questions are :
1) what are the best transistors in 2025 to replace the main 20 with.

2) it appears the original design called for 4 other transistors, what should these be replaced with?

thanks for the help

Bob

 

[laatsch55]

MJ 21196 on the 20 anf RCA 410'S as drivers..

 

[Slake]

MJ 21196 on the 20 anf RCA 410'S as drivers..

Thank you very much. I will order these today

Bob

 

[mlucitt]

Our source for Phase Linear components is:
https://www.whiteoakaudio.com/estore.aspx
But many of the technicians here carry parts such as the output transistors.

 

[wattsabundant]

MJ 21196 on the 20 anf RCA 410'S as drivers..

I second what he said, with the exception that "anf" should be "and". Sorry Lee, you were 99% correct. The RCA 410's (located at the bottom of each heat sink) are a must for stability. Mj15024's can be used for outputs. See service bulletins in attached manual

 

[laatsch55]

Don, thats whst it sounfs like when ypu have a mouthful of....

 

[WOPL Sniffer]

Hello
I am a new member to this site and this is my first post. I have been collection and repairing vintage audio gear for 15 years.
Yesterday I purchased a non working Phase Linear 700b (Serial# 2555). I believe it is a series 1?. The current transistors are 2N3773’s Motorola’s as the main 20 transistors. I read in the phase Linear service manual that the 2N’s were not a good choice.
My questions are :
1) what are the best transistors in 2025 to replace the main 20 with.

2) it appears the original design called for 4 other transistors, what should these be replaced with?

thanks for the help

Bob

Didn't know there was a 700B Series 1 or any other "Series" . There were only the 700 (original with the split face and tiny meters), 700B (big analog meters), 700 Series II (Cylon meters). Got a picture of that 700B Series 1???? We love the 1 of a kind amps. There were a couple of off the wall specimens but I never seen an amp marked 700B Series 1