Category Archives: Consumer Technology

Invention of the Microwave Oven

When the Edison Tech Center published its video with Rudy Dehn talking about how the device worked hundreds of thousands chose to watch it, however many didn’t get the full story. Yes Rudy was one of the guys who made this staple of modern kitchens available, but similarly to most other inventions it took many others to build a foundation. Notable contributors include Albert W. Hull, Kunio Yagi, C.W. Rice, Percy Spencer, and others who all contributed a bit to make the modern oven possible.

Here is a timeline for the microwave oven:

  • 1921 Albert W. Hull at the GE Research Lab in Schenectady, New York develops the magnetron
  • 1924-28 European engineers explore the magnetron oscillator. Zacek (Czech) and Haban (Germany) do work on the subject but don’t apply for any patents
  • 1928 Kunio Yagi works on multi-anode oscillators in Japan. The same year C. W. Rice demonstrates a magnetron transmitter at GE in Schenectady.
  • 1930 General Electric offers type FH-11 magnetron for sale, then later discontinues production due to lack of customers
  • 1937-40 Oliphant develops multi-cavity magnetrons in England, this becomes the first true microwave magnetron
  • 1940-45 Magnetrons were the key components of radar systems
  • 1945 Percy Spensor at Raytheon proposes a microwave oven as a peacetime spin-off of radar. The Radarange is sold to commercial and institutional users.
  • 1945-1950 GE develops magnetrons for industrial processing
  • 1950-1953 GE Range Department developed full size oven using 915 MHz.
  • 1960s GE engineers continue to work on making the power supplies smaller for the microwave oven (as well as many other applications). GE engineers including Rudy Dehn work on making the microwave oven smaller so it can be the modern countertop device we know today.
Dehn two magnetrons
Rudy Dehn holds two generations of magnetrons at the Edison Tech Center. The large device on the left is from the 1950s full sized oven. The device on the right is the compact version used in most today.
  • 1960s Japanese companies buy rights from GE and develop the 2450 MHz oven
  • 1970s Japanese manufacturers dominate the field of microwave ovens due to automated production which reduces overall cost for the consumer

Here are a few of our videos on the microwave oven:



This beast of capacitors and tubes was just the power supply for the 1960s era microwave ovens.
A new HF power supply in a modern microwave oven
1960s microwave
A happy housewife of the 1960s enjoying the fruits of engineering.
Magnetrons and other tubes on display at the Edison Tech Center
Microwave ovens from all decades on display at the ETC
The back of the 915 MHz oven model from the 1950s. The magnetron pokes into the oven cavity directly unlike modern ovens which use a waveguide to bounce waves into the cavity.
The 1953 GE oven model. The microwave oven is on the bottom. There are also calrods in the oven under the turn-table.