Nikon's first mainstream autofocus SLR — the F-501, electronic, program/aperture/manual, Nikon F, 1986.
The Nikon F-501, introduced in 1986, was Nikon's first widely produced autofocus 35mm SLR, using in-body autofocus with the new AF Nikkor lenses. It was sold as the N2020 in the United States. It built on the motorised F-301 and used the Nikon F bayonet mount, part of the long-lived Nikon lens system that carried autofocus forward.
This is an electronically controlled 35mm SLR on the Nikon F mount, with a vertical-travel focal-plane shutter that is electronically timed, offering speeds broadly to 1/2000 second plus B. Metering is centre-weighted TTL; exposure modes include programmed, aperture-priority and manual. It provides phase-detection autofocus with AF Nikkor lenses and an integral motorised film advance. As an electronic body it depends on batteries to focus, fire and wind.
The F-501 suits users who want early Nikon autofocus with automatic and manual exposure, plus built-in film advance. Autofocus works with AF Nikkor lenses, while manual-focus AI and AI-S lenses can be used with focus confirmation. It is a bridge between the manual-focus era and the later F-801 and F4 autofocus bodies.
On the used market, being fully electronic with autofocus and a motor, it needs good batteries, so test AF, the winder, meter and exposure modes. Check the shutter, inspect the prism for haze, and look for perished light-seal and mirror-damper foam, common on this era. Try loading and rewind. It uses standard AAA-type cells rather than mercury batteries. AF Nikkor lenses autofocus; AI and AI-S F-mount lenses meter and focus manually.