LETTERS

Image Gallery Jack Hees' cultivator

I found this horse-drawn cultivator at an antique shop. It was very rusty and had no handles. The single trees and one spring also were missing. I couldn't find any paint on it, even after I took off the seat and the hubcaps.

Luckily, in the July issue of Farm Collector, I saw a picture of an old cultivator just like this one. Now I know I have a Roderick Lean Leverless Cultivator. From that article I learned its true colors before the company's merger, so I painted it.

Here is a picture of it before it was painted and another as it is today. I am hoping someone might know more about it, including where I could find a replacement for the missing spring.
-Jack Hees, 124 Eldon Road, Eldon, MO 65026; (573) 392-5573

More on the 'magnetic mystery'

In response to item B, a 'What-is-it?' in the July issue of Farm Collector: The device is indeed magnetic and the source of the name 'magnetron,' which is the heart of all our current microwave ovens. The device pictured was the magnet for a military radar magnetron, which is a form of vacuum tube. The tube here was made of relatively soft metal and is not shown in your picture. The adjustable gadgetry between and below the pole pieces serves to adjust the size/position of the vacuum cavity, which sets the desired frequency to resonate with waveguide output to antenna.

If you think this all sounds magical, then read up on parametric amplifiers, which juiced up the returning echo signal. Tuning those was a black magic art. Ahh, the memories!

Growing up in rural Tennessee in the 1960s, I developed an interest in radio and had crystal radios, home-built transistor radios, modified tube radios or whatever I could find to listen to radio stations around the United States and the world. This led me into electronics in the U.S. Air Force, where I met the type of gadget shown in your magazine.
- Bob Payne, 65 Wallace Road, Coldwater, MS 38618; e-mail: bobpayne@earthlink.net