Unlike consumer reel-to-reels that used ¼" tape on 5" or 7" reels, the W9 used a unique 3-inch NAB hub reel (though adapters exist for standard reels). It recorded in full-track mono (later versions offered half-track).
First, it is crucial to clarify a common point of confusion. The "McGraw Hill" in the product name does not refer to the well-known publishing company (McGraw-Hill Education). Instead, it refers to McGraw-Edison Company, a massive American manufacturing conglomerate that produced everything from small appliances to heavy-duty industrial electrical equipment.
The W9 Portable is a high-capacity, skid-mounted or wheeled portable power distribution unit. Specifically, it is a portable substation or power center. Unlike a standard portable generator that produces electricity via an engine, the McGraw Hill W9 Portable distributes and transforms electricity. It is designed to take high-voltage primary power from a utility line or a large generator and step it down (via an internal transformer) to usable, lower-voltage secondary power for tools, lighting, and temporary facilities.
The "W9" designation refers to a specific engineering specification within the McGraw-Edison line—typically denoting a 9 kVA to 75 kVA capacity range, though field modifications were common. The "Portable" aspect is earned via heavy-duty steel skids with forklift pockets, lifting eyes, and often, rugged pneumatic tires for towing behind a service truck. mcgraw hill w9 portable
The W9 Portable is a bridge between the steam age and the hydraulic age.
Let’s be honest: modern portable power distribution units from manufacturers like Larson Electronics, Multi-Tech, or Eaton are lighter, more energy-efficient, and come with warranties. They also feature built-in surge suppression, remote monitoring, and quieter operation.
However, the McGraw Hill W9 Portable offers something no modern unit can: unconditional durability. In an era of planned obsolescence, the W9 is a machine that was built to outlast its creators. If you need a temporary power solution that: Unlike consumer reel-to-reels that used ¼" tape on
...then the W9 remains an unbeatable choice.
The core transformer of the McGraw Hill W9 Portable is often still perfectly functional, but the accessories need updating. Here is a recommended modernization path:
To understand the W9, you must first understand the era. Before the Sony Walkman Professional (WMD6C) or the Nagra III, portable recording was a nightmare of vacuum tubes and heavy lead-acid batteries. Most "portable" recorders of the 1950s weighed over 30 pounds and required a handcart. engineers documenting bridge stress tests
McGraw Hill’s industrial division pivoted in the late 1950s to serve the "business communications" market. They saw a need: field journalists interviewing subjects in noisy environments, engineers documenting bridge stress tests, and even the military needing a rugged device for "voice and signature" intelligence gathering.
The result was the W Series. The "W" likely stood for "Wireless" or "Workhorse," but by the time the W9 rolled off the production line in the mid-1960s, it had evolved into a three-motor, direct-drive system that rivaled the professional studio decks of the day—only it fit under an airplane seat.
Key Era: 1965–1975 (Though units were serviced well into the 1980s).