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Radio Shack (Realistic) Date Codes

Decoding the date code on your Radio Shack scanner is as follows

The date code consists of a number (from 1 to 12), followed by the letter "A", followed by another number (from 0-9).

The first number represents the month of manufacture, while the last number represents the year. (The "A" acts as a separator.)
For example, the date code

3A4     would decode to  March 1974 or March 1984 or March 1994

Note that the decade can't be precisely determined but a quick check in a Radio Shack Catalog will help you to determine a decade.