Hammond 1751A 15W Output Transformer, 8K C.T. Primary, Multi-Tap

The 1751A is a 15 watt tube guitar amplifier output transformer from the 1751 Series, designed for drop in replacement of original units and constructed to look similar to original factory units. The manufacturer identifies it as an ideal replacement for Gibson's Goldseal/Gold Tone GA15/GA15-RV (part number 73-TRAN-15W-OP2), making it a fit for technicians servicing those amplifiers.

It has an 8000 ohm center-tapped input impedance and 5.3, 8 and 16 ohm outputs. Frequency response is nearly flat from 40Hz to 15KHz (±1dB referenced to 1KHz at 27dBu drive). Primary DC resistances are 300.7 (red-blue), 126.9 (red-white) and 173.9 (white-blue), and secondary DC resistances are 0.445 (brown-orange), 0.548 (brown-yellow) and 0.797 (brown-green), each ±20%. At 1 KHz, 1 V, the red-blue primary shows 37H (250 K ohms) and the red-white primary 10.3H (74 K ohms); leakage inductance is 31.70mH (red-blue) and 15.44mH (red-white).

Dielectric strength is 2500V RMS and the temperature class is up to 105 degC. All leads come out at least 8 in. The drawing lists a weight of 1.32 lbs, while the shipping weight on the part page is 0.4 lbs (0.18 kg).

Dimensional details on the drawing include 2.188 in, 1.750 in, 2.625 in, 2.563 in, 2.062 in (REF.) and 1.563 in, with mounting slots of 0.188 x 0.250 in. The 1751A is RoHS and REACH compliant. Hammond is not affiliated with Gibson; amplifier model names are listed for reference only.