Hammond 842A Push-Pull Plate to 125/500 Ohm Line Transformer

The 842A is an 800A Series broadcast-quality output transformer for push-pull (P.P.) plates to line. Its primary is a nominal 5K/20K ohms (6K/24K ohms also listed) and its secondary 125/500 ohms (150/600 ohms also listed), matching a push-pull tube stage to a standard 600 ohm class line.

The "**" note on this model in the series table means a single plate requires parallel feed. The maximum primary D.C. unbalanced current is listed as 0. Frequency response is +/- 0.5 dB max. from 50 Hz to 15 kHz, insertion loss is approximately 1 dB, and the maximum power level is +20 dBm with the specified characteristics, or higher with reduced low frequency performance. Along with the 841A and 844A, it is one of the three 800A models rated at +20 dBm rather than +15 dBm.

Humbucking construction helps reject stray magnetic fields, and balanced split windings on both primary and secondary give circuit versatility; the primary may be used as the secondary and vice versa for impedance matching.

It is housed in a deep-drawn steel case with a tin plated finish and fastens with two 6-32 mounting studs, supplied with hardware. Connections are made by wire leads of at least 4" in length. Maximum overall dimensions are 1.75" (44.5 mm) wide x 1.25" (31.8 mm) deep x 2.56" (65 mm) high. The 842A is RoHS and REACH compliant. Its listed shipping weight is 0.55 lbs (0.25 kg), and it is identified by UNSPSC 39121301.