Lundahl LL1927A Audio transformer

The LL1927A is a very high turns ratio transformers for active ribbon microphones. The transformer has an uncut amorphous strip core and is built up from two coils of each four sections for low leakage inductance.

Turns Ratio:  1 + 1 : 55 + 55

Technical Details:

• Dims: (Length x Width x Height above PCB (mm))                                               30 x 22.5 x 14.5

• Spacing between pin positions:                                                                              2.54 mm  (0.1")  

• Spacing between rows of pins:                                                                               22.86 mm  (0.9")

• Weight:                                                                                                                     27 g

• Rec. PCB hole diameter:                                                                                         1.5 mm

• Housing:                                                                                                                    Mu metal

• Core:                                                                                                                          High mu amorphous strip core

• Static resistance of each  primary (average):                                                         0.05 ohms

• Static resistance of each secondary:                                                                        182 ohms

• Frequency response (Source 0.3 ohms, load 10k ohms.                                           10Hz – 70kHz +/- 1dB

                                              Connection 1 : 110. Secondary signal level 0dBU)