Lundahl Line output transformer, LL2811

Audio Output Transformer LL2811

LL2811 is an audio output transformer for balanced drive, with the following features:
1. Four section winding structure for small leakage inductance.
2. Ideally used 2 : 1 (secondaries in parallel) with e.g. NE5532 op amps for low noise.
3. Precision made audio C core for small size.
4. Two-coil structure and mu-metal housing for high magnetic noise immunity.
5. Designed to fit three in a row across a Euroboard. The secondaries can be connected in parallel for low output impedance or in series for high output level.

Turns ratio: 1 + 1: 1 + 1
Dims: (Length x Width x Height above PCB (mm)) 31 x 26x 23

Spacing between pins: 2.54 mm (0.1")
Spacing between rows of pins: 22.86 mm (0.9")
Weight: 65 g
Rec. PCB hole diameter: 1.5 mm
Static resistance of each primary (average): 45 ?
Static resistance of each secondary (average): 45 ?
Max. primary level (primaries in series) +30 dBU @ 50 Hz
Leakage inductance (windings in series): < 1 mH
No-load impedance(primaries in series, primary level): > 750 ? @ 50 Hz, +20 dBU
Balance of output (according to IRT, source < 10 ? , Load 600 ?): > 55 dB
Frequency response (source 10 ?, load 600 ?, 0 dBU): 10 Hz -- 100 KHz +/- 0.3 dB
Isolation between primary and secondary windings/ between windings and core: 4 kV / 2 kV