Hammond 106X 500 CT to 8 Ohm Output Audio Transformer, 1.5 W

The 106X is the 8 ohm version of the 500 ohm output transformers in the 106 Series. Its 500 ohm centre-tapped primary and 8 ohm secondary give a large step-down ratio for low-current output stages driving 8 ohm loads from a PC board.

It is rated for 1500 mW output with 1 dB insertion loss and a -1 dB low frequency roll-off at 170 Hz; the drawing specifies ±1dB from 170Hz to 20KHz at 20dBu. The primary accepts up to 10 mA DC. DC resistance is 26 ohms primary and 0.7 ohms secondary (+/- 15%) in the ordering table; the drawing lists 12.69 ohms (pins 1-2), 12.83 ohms (pins 2-4) and 660 mOhms (pins 5-8). Primary inductance is 555.8mH (4.56K ohms) and leakage inductance 3.73 mH at 1V, 1KHz.

Construction is rugged black epoxy potting that produces a completely sealed unit able to withstand severe environmental conditions, including those of MIL-T-27 (Grade 5, Class S). Centre-tapped windings use a bifilar technique for balanced resistive and capacitive characteristics, and the series carries a peak working voltage rating of 200V. The part drawing gives 500V RMS dielectric strength, a 105°C temperature class and a 50,000 ft. maximum operating altitude.

It mounts directly to a printed circuit board on square pins (0.025" square typical); where a connection is not used, no pin exists. It is REACH and RoHS compliant. Mechanical outline is Figure 8; the drawing weight is 1.44 oz. and the shipping weight 0.09 lbs (0.04 kg).