The manual includes a flow chart for:
Do not rely on forum posts alone. Download the official PDF (Z3801-90001 Rev B), print the schematics, and keep them near your workbench. With the manual in hand, your Z3801A will continue to provide sub-nanosecond timing and ultra-low phase noise 10 MHz for another 20 years. z3801a service manual
Didier Juges (ex-HP engineer) hosts a mirror of rare HP documents. His site includes schematics and theory of operation not found in the condensed user guides. The manual includes a flow chart for: Do