AIR-AP1840I-F-K9C Cisco Aironet 1840I 4x4 MU-MIMO Mobility Express AP

AIR-AP1840I-F-K9C F-Domain Mobility Express AP

AIR-AP1840I-F-K9C is the F-domain Mobility Express order of Cisco's Aironet 1840. It combines a 2x2 2.4 GHz radio with a 4x4:4 5 GHz 802.11ac Wave 2 radio, four internal antennas and two Gigabit Ethernet interfaces.

F-domain narrow 5 GHz plan

Cisco lists thirteen channels at 2.412-2.472 GHz, four at 5.250-5.350 GHz and four at 5.725-5.825 GHz. Preserve this F-specific plan during controller setup and verify current country approval rather than importing the broader AIR-AP1840I-B-K9C configuration.

K9C image and recovery evidence

Cisco's getting-started guide defines K9C as factory-shipped with a Mobility Express software image. Used inventory may have changed roles or images, so capture the running version, configured country, primary/subordinate state, configuration backup and restore result.

PoE and interface acceptance

Test both autosensing Gigabit Ethernet ports and PoE negotiation. Cisco specifies 13.2W at the PSE with all features except USB and 17.8W with USB; under 802.3af the USB port is disabled. Record actual power mode, link state, mount, radio health and client performance.

Lifecycle decision

Cisco lists this exact F-domain K9C PID as end of sale and directs migration to Catalyst 9115AX. Last support is 30 April 2027, so remaining entitlement and replacement timing belong in the procurement record.

Official evidence: Cisco F-domain spectrum, radio and power data, Cisco K9C software and installation guide, Cisco exact F-domain lifecycle row and Cisco country approval lookup.