This is a vintage instructions tube specifications manual from Eitel-McCullough Inc, covering models 4-65A, 4-125A, 4-250A and more. It provides detailed information on the operation and maintenance of these tubes, which were commonly used in vintage audio and video equipment. The manual is a valuable resource for collectors and enthusiasts of vintage electronics, and is a great addition to any collection of vintage manuals and literature.

Great collection of vintage manuals and product specifications for various modulators amplifier calculations etc