====== HP 400E 10MHz AC Voltmeter ======
{{ :electronics:hp_400e_el_ac_voltmeter.pdf |400E User and Service Manual (Indexed, Good Scan)}}\\
{{ :electronics:hp_400e_service_manual.pdf |400E User and Service Manual (Searchable Text)}}\\
{{ :electronics:hp_journal_january_1966_-_hp_400e.pdf |HP Journal Vol. 17, No. 5 (January 1966) featuring the HP 400E}}