The following is a revised AL-80B power supply board schematic. It also applies to all amplifiers in the AL80 mainframe with suitable changes in R106 and R107:

AL80B power supply 

J101 pin outs CCW from top view at index:

1 (-) meter plate current
2-6 ground
7 +12V 
8 antenna relay from STBY-OPR switch
9 high voltage metering, 1 mA = 3500V
10 ALC out
11 ground
12 grid meter (+), plate current meter (-)
13 -12V
14 reflected power
15 forward power
16 +12V


C101 is SWR compensation on bypass. Value can change.

C106 is release time for auto-bias. See EBS electronic bias page for circuit description.

Additional revised schematics will appear on this page.