Vintage audio publications!
Here we have scans of old magazine articles, brochures, etc. Thanks to Tony Daggs for many of the scans!
Many files on this site, especially scanned documentation, are in Adobe Acrobat (PDF) format. I recommend that if you don't already have it you download the latest version of Adobe reader. Some files have compressed images that may not work correctly with older versions of Acrobat reader.
Vintage catalogs and brochures:
Potter & Brumfield relay catalog from 1952 (1.3MB PDF file) Courtesy of Gary Smith
Thordarson Amplifiers, brochure with schematics for a number of early amps (3.8MB PDF file) Courtesy of John Atwood
RCA High Fidelity Amplifier Circuits, RCA brochure with Hi-Fi schematics from 1959 (3.6MB PDF file)
Theory and Operation of the Ultra-Linear Circuit from Keroes Enterprises, the patent holder (250kB PDF file)
Dynakit MKII brochure (1MB PDF file)
Altec home hi-fi catalog (3.4MB PDF file)
"You Can Build Your Own Hi-Fi Speaker Systems", 18 speaker plans from Jensen Speakers (BIG 12MB PDF file)
"Metallic Rectifier Design and Application", a selenium rectifier catalog from radio Receptor Company, Inc. (2MB PDF file)
Cannon audio connector catalog RGC-8 (CAUTION LARGE 68MB PDF file) Courtesy of Chuck McGregor, N7RHU
Amphenol catalog "Quality Components for Radio and Electronics" (CAUTION LARGE 55MB PDF file) Courtesy of Chuck McGregor, N7RHU
Selenium Rectifier Handbook by Sarkes-Tarzian Company (4.5MB PDF file) Courtesy of an anonymous donor
Vintage test equipment info:
Alphabetical by manufacturer
NEW 1/21/19 - Rhode & Schwarz RC-Generator type SRB Thanks to Alicia & Jim Z
B&K 747 tube tester manual (1.9MB PDF file) Courtesy of John Atwood
B&K 747 tube tester schematic (158kB PDF file) Courtesy of John Atwood
Ballentine 300 AC voltmeter (703kB PDF file) Courtesy of John Atwood
Ballantine 300D AC voltmeter (1MB PDF file) Courtesy of John Atwood
Ballantine 320 True-RMS voltmeter (MB PDF file) Courtesy of Joe Sousa
Boonton 75D capacitance bridge (4.5MB PDF file) Courtesy of John Atwood
Hickok TV-3U tube tester manual (7.5MB PDF file) Courtesy of John Atwood
Sound Technology 1700AB Audio Analyzer manual (4.1MB PDF file) Courtesy of John Atwood
Vintage manuals and service data:
McIntosh service data is on its own page
Alphabetical by manufacturer
Schematic of Allen Organ model 75 amp (62kB PDF file)
Schematic of Allen organ model 90 amp (54kB PDF file)
Conn Strobotuner manual (with schematic) (356kB PDF file)
Service info for Echolette S40 guitar amp (735kB PDF file)
Service info for Echolette BS40 guitar amp (1.2MB PDF file)
Heath W3AM manual (3.5MB PDF file) Courtesy of John Atwood
Heath W3M manual (3.3MB PDF file) Courtesy of John Atwood
Heath W4AM manual (3.3MB PDF file) Courtesy of Micah Gregory
Heath W5M manual (4.6MB PDF file) Courtesy of John Atwood
Service info for Hohner 60MH guitar amp (629kB PDF file)
National HRO-5A1 manual (2.0MB PDF file) Courtesy of John Atwood
Oliver guitar amp info, including schematics, photos, etc. (687kB PDF file)
Vintage magazine articles and papers:
New 1/7/17 - CDE (Cornell-Dubilier, the capacitor company) published a series of mini magazines called "The CD Capacitor". Interesting material, various topics with practical hints and circuits. PDF files, 1-2MB each.
A letter and collection of papers from Dr. Alexander Bereskin. Dr. Bereskin was a long time professor of Engineering at the University of Cincinnati. He provided the following material to be published:
Introductory letter and biographical data (72kB PDF file)
"Build It Yourself - A 50 Watt High Quality Audio Amplifier" (5.4MB PDF file)
"A 3,000-Watt Audio Power Amplifier" (160kB PDF file)
"A High Efficiency - High Quality Audio Frequency Power Amplifier" (315kB PDF file)
"A Dual-Channel Transistor Power Amplifier" (195kB PDF file)
"Amplifier Response Stability and All That" by John Moyle, from Radio, Television, and Hobbies (7.2MB PDF file) - Thanks to G. Kleinschmidt!
A McIntosh Audio Amplifier Incorporating a Trifilar Output Transformer", a thesis by Hugh Alvin Lockhart. It describes an amp built with a trifilar OPT, with one winding for the plate, one for the screen grid, and one for cathode feedback. Separate windings allow the plate voltage to be run higher than the screen. Has details of OPT construction. 1.3MB PDF file.
"Modernize your Williamson" by David Hafler, from Audiocraft, January 1956 (1.2MB PDF file)
"A 100W power amplifier" by A. Kenneth Olson, from 1955 Radio & Television News, reprinted by Chicago transformer (1.7MB PDF file)
"Getter Materials" from Electronics, October, 1950 (1.4MB PDF file)
"Vacuum Tube Heaters" from Electronic Industries, December, 1961 (937k PDF file)
"Construction Details About a Preamplifier of Improved Design", Audio Facts, June, 1955 (1.4MB PDF file)
"The James- Baxandall Passive Tone-Control Network", a paper by Ramon Vargas Patron (753kB PDF file)