Gates Division (Harris-Intertype) BC-5H

Overview

The BC-5H is a high-power AM broadcast transmitter produced by the Gates Division of Harris-Intertype. It was designed for medium-wave broadcast service and rated for 5 kW carrier output. The BC-5H was part of the widely used Gates BC-series transmitters found in AM radio stations across the United States.

Technical Specifications

ItemDetails
ManufacturerGates Division, Harris-Intertype Corporation
ModelBC-5H
TypeAM Broadcast Transmitter
Frequency Range530–1700 kHz (medium wave broadcast band)
Power Output5 kW
ModulationHigh-level plate modulation (AM)
Frequency ControlCrystal-controlled
Power RequirementsThree-phase AC (station dependent configuration)
CoolingForced air
Tube LineupVacuum tube (RF final and modulator stages)

Physical Description

The BC-5H is a floor-standing transmitter consisting of multiple steel cabinets housing RF, modulator, and power supply sections. The front panels include meters for plate current, voltage, modulation level, and system status, along with control switches and interlocks.

The design follows traditional broadcast transmitter construction, with large transformers, high-voltage power supplies, and forced-air cooling systems. Access panels allow servicing of tubes and internal components.

History

The BC-5H was introduced during the period when Gates operated as a division of Harris-Intertype, following the 1957 acquisition of Gates Radio Company. It represents the evolution of Gates’ earlier BC-series transmitters, incorporating refinements in reliability, serviceability, and performance.

Transmitters in the BC-series, including the BC-5H, were widely deployed in AM broadcast stations during the mid-20th century. Their robust construction and straightforward design contributed to long service life, with some units remaining in operation or preserved by broadcast engineers and collectors.

The BC-5H reflects the transition era branding of Gates under Harris-Intertype, prior to the later Gates-Harris and Harris naming conventions.

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