Crystal Set
1923

Atwater Kent never sold a completely assembled crystal set. The set shown above was assembled from individual components marketed by the company in the early 1920's.

Model 1
1922

To see an example of an Atwater Kent breadboard ad with the variometer sold as a separate item, click here.
 

Model 2
1922

Model 2
Homebrew

Kent offered an additional stage of audio amplification with the 3-tube Model 3945 (also known as the Model 2.) It was shipped about the same time as the Model 1.
 

Model 3
(3955)
1923

In the Model 3955, Atwater Kent's designers separated the detector tube in order to produce a clearer signal, free of interference from the audio amplifier.

Model 3955
(1923)

This version of the 3955 includes an RF amplification stage instead of a variometer.  This improved sensitivity without making the set regenerative.

Model 3975 (SOLD)
1923
(Reproduction board)

Model 6
(4052)
1923

In order to increase sensitivity, Atwater Kent added an RF amplifier to the existing "Open Receiving Set Model 3945" to create the Model 6.

Model 4066
1923

Introduced in early 1923, the 4066 added another stage of RF amplification, eliminating the need for a regenerative circuit.

Model 5
1923

About 9 months later the Model 5 appeared. Virtually identical electrically to the 4066, it is one of the first examples of a "compact" design. Unfortunately the unit didn't perform well and was discontinued. The Atwater Kent Model 5 is quite rare and is highly prized by vintage radio collectors.

Model 9
1923

The Model 9 was introduced shortly after the Model 5, returning to a single stage of RF amplification, but with a second variometer.

Model 4660 ("9C")
1924
 

Model 4445
1923

The Model 4445 is a version of the Model 9 using terminal posts instead of a battery cable.
 

Model 10
Radiodyne
1923

The Radiodyne was introduced in the fall of 1923, employed two stages of RF amplification and was the first successful AK radio employing condenser tuning (The Model 8, introduced at the same time as the Model 5 also used a single tuning condenser, but it did not sell well). The Radiodyne was built in order to capitalize on the popularity of the new 3-dial, 5-tube TRF Neutrodyne radios such as the FADA 160 and Freed Eisemann NR-5. Unfortunately the "Radiodyne" trademark was already held by Western Coil, so Atwater Kent was forced to discontinue the unit. The Radiodyne is distinguished by its green tuning condenser cans and the "Radiodyne" label on the transformer tops.

Model 10A
1924

The Model 10A was introduced to replace the Radiodyne. It can be distinguished from the other Model 10's by its vertical RFcoils, the presence of a separate potentiometer located between the first and second stage, and the lack of a switch on the first RF coil.

Model 10B
1924

The Model 10B is recognized by the orthogonal (sideways mount) RF coils, the presence of a separate potentiometer located between the first and second stage, and the presence of a switch on the first RF coil.

Model 10C
1924

Model 12
1924

Note: For an in-depth look at Atwater Kent and many other radio manufacturers of the 1920's, see "Radio Manufacturers of the 1920's" by Alan Douglas. This great three volume set can be purchased online through Antique Radio Classified.