User's Manual

ALPHA 9500 Interim OPERATING MANUAL
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This board is housed in the tube deck and consists of a set of Pi-L filters controlled by a set of 5
relays which are enabled, based on the band switch setting to choose which filter to use.
5.9 Center Partition Board
This contains the RF decoupling circuit on the B+ line as well as the “crowbar” safety circuit. This
safety device consists of a piece of spring metal, which shorts out the B+ line when the top cover
of the amplifier is removed.