Hammond 108K 1.5K:600 Ohm Center-Tapped Audio Transformer, 500 mW

The 108K is a 108 Series 500 mW miniature audio transformer that couples a 1.5K ohm centre-tapped primary (pins 1-3) to a 600 ohm centre-tapped secondary (pins 4-6) at a 1.58:1 turns ratio. It is suited to driving a 600 ohm line from a 1500 ohm source, and to the input, isolation and output roles the series covers.

Power level is 500mw from 300 Hz. to 50 Khz., typical output power 0.500 Watts. At +0, +15 and +27 dbm the frequency range is 300 Hz. to 50 Khz. +/- 1.5db (no D.C. saturation); the frequency response is ±1.5db from 300Hz to 50KHz. Typical DCR is 140 ohms primary (70/70) and 66 ohms secondary (33/33), with table values of 170 and 69 ohms (+/- 20%). Inductance is 2.40 H primary and 0.94 H secondary, leakage 6.50 mH, and impedance 21.5 K and 9.0 K ohms at 1.0 kHz, 1.0 V. The ordering table gives a maximum D.C. unbalance of 4 mA, while the drawing lists unbalanced DC as 6mA max. Dielectric strength is 100 Vrms.

Like the rest of the 108 Series, it is epoxy potted in an attractive black molded case that forms a completely sealed unit able to withstand severe environmental conditions. It withstands soldering for 10 sec. at 260 degrees C with ambient temperature 85 degrees C max., and the casting epoxy is workable from -40°C to +105°C under a normal rate of change (thermal shock excluded). The drawing notes the windings may be used either way round.

It mounts on a PC board with pin-type terminals of min. 0.187" length, is RoHS and REACH compliant, and has a shipping weight of 0.08 lbs (0.04 kg).