Hammond 1140-LU-EPC +22 dBu 80% Nickel PCB Line Output Transformer

The 1140-LU-EPC is a printed circuit board mount line output transformer from the 1140-PC Series, with a 600:600 impedance ratio and 1:1 turns ratio. It is intended for transformer-coupled line outputs on audio circuit boards.

Hammond's drawing describes bi-filar windings and an 80% nickel core, giving very low distortion levels and good output levels. The part can drive 600 Ω loads up to +22 dBu at 20 Hz. The drive signal should have no DC component and the source impedance should be as low as possible because of the nickel core's properties.

This part has a particularly flat typical response: -0.03 dB at 20 Hz and +0.02 dB at 20 kHz (0 dBu). THD is 0.007% at 1 kHz and 0.001% at 20 Hz (4 dBu), and the series ordering table lists 0.007%. Common mode rejection is 105 dB at 60 Hz and 85 dB at 3 kHz; phase shift is 0.08° at 20 Hz and -0.80° at 20 kHz.

DC resistance is 40 Ω for both primary and secondary at 20°C, primary input impedance 680 Ω and secondary output impedance 80 Ω at 1 kHz. Capacitance is 20 nF primary to shield and case and 70 pF secondary to shield and case; dielectric strength is 250 Vrms. The 1140-LU-EPC uses PIN 2–PIN 4 for the primary and PIN 11–PIN 8 for the secondary, ships at 0.2 lbs (0.09 kg) and is RoHS and REACH compliant.