Help with a Heathkit Ar-1500, not the A

[donhradio]

Hi, looking for help in repairing a Heathkit AR-1500. I don't have the complete manual, only the schematic. I "blew" up diode 703 on the power output board. On the schematic it looks like three diodes in series in one part. So, A) Can anyone provide help with identifying this diode with a part number wherein I may purchase replacement parts? B) Can anyone help me understand the function of this diode in the power amplifier circuit?

Hey thanks in advance. I really can't wait to get this relic functioning!

In general, I enjoy repairing vintage electronics of any kind, no mater how old. Been restoring electronics for more than 50 years, but obviously, still room to learn something new! Like what does that diode do and how do I replace it

 

[Markoneswift]

There's some mention of that diode here in another AK thread - https://audiokarma.org/forums/index.php?threads/ar-1500-heathkit-part-number-equivalent.898304/

 

[Doug G.]

The triple diode maintains the forward bias on the driver transistors and thus to the output transistors so they operate in class AB.

Doug