Absorption lines detected toward NRAO 150. The left panel shows previous detections including the o-H₂CO (1_1,0–1_1,1) line at 4.8 GHz and the o-c-C₃H₂ (1_1,0–1_0,1) line at 18 GHz observed at the VLA (Liszt & Lucas 1995; Liszt et al. 2012), and the CS (2–1) (98 GHz), o-c-C₃H₂ (2_1,2–1_0,1)(85.3 GHz), CCH(1, 3/2, 2–0,1/2,1) (87.3 GHz), and HCO⁺(1–0) (89.2 GHz) lines (Liszt & Lucas 1995; Lucas & Liszt 1994, 1996, 2000, 2002) observed with the PdBI. The right panel presents the new observations including the o-H₂CO(2_1,1–1_0,2), o-H₂¹³CO(2_1,1–1_0,2), and p-H₂CO (2_0,2–1_0,1) lines, the CS (3–2), C³⁴S(3–2) lines, and the c-C₃H₂ transitions listed in Table 2. All displayed spectra have been normalized by the continuum strength. Vertical offsets have been used for clarity.