DATE CODES ON TUBE CHARTS

On Fender Amplifiers made after 1953, there is a date code stamped onto their tube charts. These charts are found on the inside cabinet of combo models, and on the amp head of piggy-back models. This date code is rubber stamped in ink, and consists of two, small letters. The first letter stands for the year, and the second letter indicates the month of manufacture.The procedure can be found by this chart:
A - 1951/January
B - 1952/February
C - 1953/March
D - 1954/April
E - 1955/May
F - 1956/June
G - 1957/July
H - 1958/August
I - 1959/September
J - 1960/October
K - 1961/November
L - 1962/December
M - 1963
N - 1964
O - 1965
P - 1966
Q - 1967
R - 1968
S - 1969
This code starts on January 1951, even though it was not introduced/used until 1953.
Here are some examples of what Fender tube charts look like. The Super Reverb has a date code of QH, which means it was produced August of 1967. The other two tube charts are from later models (Silverface's). Production dates on tube charts was discontinued around 1969 or 1970.
Fender started using a date code again in 1990 that was very similar to the one used in the 1960s and 70s. The code is located on the black and silver QA (Quality Assurance) sticker on the back of the amp. Among all the lines/numbers on this sticker, the last two letters indicate the date - the first letter indicating the year and the second letter indicating the month. Here is a chart for these amplifiers:
A - 1990/January
B - 1991/February
C - 1992/March
D - 1993/April
E - 1994/May
F - 1995/June
G - 1996/July
H - 1997/August
I - 1998/September
J - 1999/October
K - 2000/November
L - 2001/December
M - 2002
N - 2003
O - 2004
P - 2005
Q - 2006
R - 2007
S - 2008
T - 2009
U - 2010
V - 2011