Dating fender power transformers
If the transformer was read from a silverface Vibro Champ we can deduce it was made in 1974 – almost…
Remember that this is when the transformer was manufactured.
A00100 to A02000 – 1964 A01200 to A08100 – 1965 A08100 to A17000 – 1966 A16000 to A21000 – 1967 A20000 to A26000 – 1968 A25000 to A28000 – 1969 A28000 to A29000 – 1970 A29000 to A32000 – 1971 A32000 to A35000 – 1972 A33000 to A39000 – 1973 A39000 to A42000 – 1974 A42000 to A51000 – 1975 A51000 to A53000 – 1976 Export models had serial numbers that started with a “B” rather than with an “A”.
Transformer / Speaker / Pot Codes American-made electronic components of that era usually have codes to indicate manufacturer and date of production.
was made can be determined through a variety of sources.
Cabinet Sticker By far the most reliable way to date your amp is to look for the month/date code stamped on the tube layout sticker on the inside of the cabinet.
These are usually in the form of a six-digit number with the following formatting scheme: The first three digits represent the manufacturer code, the next digit represents the year of production and the last two digits represent the week of production.
Thus as an example 606452 is a transformer code: 606 tells us it is a Schumacher transformer made in either 1964 or 1974 and and it was built on the last week of December.
It could be that another transformer reads 606602 which would make that component a 1976 make, thus the earliest the amp could be is a 1976.His particular area of expertise is in Fender amps made from about 1960 through 1967.