This amplifier has been around for awhile, however the date code on the Altoids tin is “Use by 22 Aug 06”, so it had to be made sometime not long before that date or later, most likely later. I used a high gain, low noise Japanese transistor (looks like a 2SD636) for the preamplifier, and two 2N3904 transistors. The Altoids tin was a convenient size to hold everything, as can be seen in the pic.
Originally the miniature electret condenser microphone on the left side of the tin was directly connected to the input. Later I added the microphone jack.