Dating a fender twin reverb
Also note the vertical black lines on the control panel (found on earliest silverface amps) and the large ceramic power resistors coming off the power tube sockets which indicates the AB568 circuit. But really, these cabs were large because they were of a “special design” that “greatly improves tone and volume without distortion, and permits optimum performance of the speakers.” At least that’s the reason according to the ’69 catalog.
Also, another thing I’ve never seen before is a what appears to be a shipping tag of some sort (see photo).
One has to wonder where all those factory original export back panels are! Another interesting tidbit is that a lot of Fenders were imported into Australia in the late 1950s and early 1960s that were stock 110-volt (domestic US) units.
Although his job was somewhat limited, his recollections provided some really fascinating insights to how the amps were built.
For instance, he confirmed our assumption that the amp chassis were put into stock after being stamped with serial numbers and that the chassis were pulled from the stock bins randomly (just as with Fender guitar neck plates).
They were something to behold, all chatting away while soldering so quickly, it didn't hardly seem like they were looking at the amps.
After that the foreman would add the tubes, turn 'em on and set the bias.” Export models – We’ve confirmed that Fender amps were distributed by Hagstrm in Sweden.
There is some debate about how to interpret the production code information on late ‘50s to mid-1967 tube charts and Greg Huntington is still working with those.
One thing we know for sure is that production codes can help date an amp to a particular month within a given model run.
These are marked with EIA code “606” which is the company number for Schumacher.
Well, this universal “truth” was debunked when we found a bunch of amps with transformers made by the Better Coil and Transformers company.
Of course I tended to hurry more when they were there, and I would fumble more, too.” Another really interesting fact was that he recalled that the eyelet boards were loaded/wired/soldered in Mexico!
“I remember the circuit boards were pre-made, from Mexico, easy to screw into the chassis. When we had filled our cart we'd wheel it over to the Chicano chicks.
Not only that, but to meet Swedish safety codes, Hagstrm removed the external voltage selector switch (fitted to all blackface and silverface export models) and hardwired it internally (see photos).