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:
J101 pin outs CCW from top view at index:
|1||(-) meter plate current|
|8||antenna relay from STBY-OPR switch|
|9||high voltage metering, 1 mA = 3500V|
|12||grid meter (+), plate current meter (-)|
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.