This is a practice sample of the very large amount of digital files of the test equipment and operating manuals for electronic devices from about 1900 to the mid 50s. I have collected and digitized over 5,000 manuals covering electronics, firearms, aircraft, do it yourself projects, boats etc. How many I list will depend on the buyers actions and requests. I you need a special manual drop me a line and ill see if i have it on file.