842

Overview

The Hammond Manufacturing 842 is an isolated audio transformer designed for broadcast applications, featuring a parallel-plate primary to line secondary configuration. It operates within a frequency range of 50 Hz to 15 kHz and utilizes wire lead termination. The unit has a single channel, measures 44.5 mm in length, 31.8 mm in width, and 65 mm in height, with a weight of approximately 249.5 g. Electrical specifications include a primary impedance of 20 kOhms and a secondary impedance of 500 Ohms. The component is shielded and belongs to the 800 series.

Feature Summary

• Broadcast-grade audio signal transformation with parallel-plate primary to line secondary topology
• Electromagnetic shielding for noise reduction in sensitive audio circuits
• Isolated construction ensuring galvanic separation between input and output stages

Applications

• Professional broadcast audio systems
• Signal interfacing between plate circuits and transmission lines
• Audio equipment requiring high-impedance isolation

Procurement Notes

Verify manufacturer part number accuracy against official Hammond Manufacturing documentation. Confirm that the specific variant matches the required electrical parameters, including 20 kOhm primary and 500 Ohm secondary impedances. Ensure the wire lead termination type aligns with system integration requirements. Check for any superseded models or updated datasheets prior to final procurement decisions.

Selection Notes

Select this component when designing broadcast audio interfaces requiring a 20 kOhm to 500 Ohm impedance match. The 50 Hz to 15 kHz frequency response suits standard voice and music transmission needs. Consider the physical dimensions and wire lead termination style for enclosure compatibility. This model is suitable for applications demanding isolated, shielded audio signal transfer.

Part Context

The 842 belongs to the Hammond 800 series of audio transformers. It is specifically engineered for broadcast environments where signal integrity and impedance matching are critical. The design supports direct connection from high-impedance plate circuits to lower-impedance line inputs, facilitating efficient signal transfer in professional audio infrastructure.

Replacement Considerations

DigiKey lists the 842 as no longer manufactured. Verify current availability status through authorized distributors. Consult Hammond Manufacturing for officially confirmed substitute part numbers if discontinuation affects production timelines.

FAQ

What is the primary-to-secondary impedance ratio of the 842?

The 842 features a primary impedance of 20 kOhms and a secondary impedance of 500 Ohms.

Does the 842 transformer include electromagnetic shielding?

Yes, the 842 is a shielded audio transformer designed to minimize interference in broadcast applications.