Hammond 143H 1500 to 500CT Ohm Chassis Driver Audio Transformer

The 143H is a driver audio transformer in the 143-146 Series, with a 1500 ohm primary and a 500 ohm center-tapped secondary. It is listed for driver applications and suits builders of chassis mounted audio equipment who need a small center-tapped driver transformer.

The 143H carries 4 mA of primary D.C. current and is rated for 30 mW output. D.C. resistance is 111 ohms primary and 24 ohms secondary, both +/- 15%.

Mechanically, the 143H is a small, economical open type transformer with a two hole horizontal bracket for chassis mounting and overall dimensions of A 1.26 in (32 mm), B 0.69 in (18 mm), C 0.69 in (18 mm) and D 1.06 in (27 mm). It uses insulated, color coded flexible leads at least 4" long, and net weight is 0.5 oz. Where a P.C. board mounted version of this style is needed, the manufacturer refers to the 148 and 149 series.

Frequency response is 150 Hz to 15 kHz within +/- 1 dB, referenced to 1000 Hz. The manufacturer notes that operating at impedances below nominal lowers power capability and frequency spectrum proportionately, while higher impedances raise them. It follows schematic 2 in the series table and is listed as RoHS and REACH compliant (UPC 623980191102).