2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/203952We describe an electron spectrometer designed for a precision measurement of the neutron $β$-asymmetry with spin-polarized ultracold neutrons. The spectrometer consists of a 1.0-Tesla solenoidal field with two identical multiwire proportional chamber and plastic scintillator electron detector packages situated within 0.6-Tesla field-expansion regions. Select results from performance studies of the spectrometer with calibration sources are reported.30 pages, 19 figures, 1 table, submitted to NIM ANuclear Experimenttext