The Hammond organ, created by a company of the same name, was originally intended for use in churches during the 1940s, but by the late 1950s it had become associated with rock, blues and jazz. A simple dictionary definition of the instrument is "an electric organ with two keyboards, electronic tone generation, and a wide variety of tone colors." The age of your Hammond can be determined by checking various components against a master list.
Use the Tonewheel General Hospital website to check the age of your organ by comparing Electronics Industry Codes located on the organ to those on the list. According to Tonewheel: "Thanks to the Electronics Industry Association (EIA) codes conveniently placed on them by the manufacturer, many individual components can be dated to the year and week of production."
To identify the location of the EIA codes check the tubes (or valves). Examine each tube and write down the number codes located on them. Refer to the Tonewheel General Hospital website and compare the numbers to the tubes section. The numbers on the tubes often describe a year directly, with the first two digits referring to the year and the last two to the week in that year.
Examine the speakers and write down the number codes written on them. Refer back to the Tonewheel General Hospital website and compare codes.
Continue this process for the Hammond Cabinet and other components. First check the code of each component, write it down, then refer back to the Tonewheel website. Check the external features for more information as to the age of your organ. Scroll down the page of the Tonewheel website and compare the information located in the table with the external features on your organ. For example, if your organ has a pilot light the table indicates it was created after 1961.
Look for a serial number on the organ and compare it with the Tonewheel website listing in the serial numbers section.
Another option is to use the Vintage Hammond website for an evaluation of your Hammond organ. This costs $5.95 and will provide you with information about the age and value of your organ.
Some components may have been changed on your organ over time so compare more than one set of codes to accurately attain the age.
Ensure the organ has been switched off and the tubes are cold before touching them.