Saturday, April 30, 2011

The Redhead

I've got the Redhead opened up on the operating table for mods and refinement and there are some slight modifications to the power supply. The 39 ohm dropping resistor was eliminated and the electrolytic capacitors were different values-33, 22, and 10 uf. Of course they were Rubycons which I do not like as I have learned to distrust electrolytics that are crimped with insulation on both ends-it often means that a smaller component has been subbed inside a larger can and Rubycon has had a reputation for that.

The ones I've got right now are Elum 47 uf and Sanwha 22 uf numbers-they seem to perform well in everything I've put them in, including a trio of Deluxe Reverbs.

I loaded the Redhead with what I'm calling the stage 1 power supply upgrade-replacing the filter capacitors with 47, 22, and 22 uf 450 volt items and replacing the 10w and 5w ceramic dropping resistors with a pair of 2w numbers. As there is an extra slot freed up I may parallel the first electrolytic and add that to the stage 1 power supply upgrade. As to why I'm ditching the big ceramics, the extra capacity is simply unnecessary and they take up too much space. If they were needed Fender would have done it long ago.

I also replaced the pilot light assembly with one from Fender as the original was the same piece of (mostly plastic) junk as I found in Brownie.

As part of this package I'm replacing the three octal tube sockets with some bakelite numbers and incorporating the rectifier diode protection mod into this package. In addition I'm replacing the ceramic grid stoppers and screen resistors with Fender values mounted on the socket. There's no need for anything larger than what Leo used and it makes for a cleaner installation.

I'm working my way along the board and I hope to find why the two channels are voiced differently, on my way to changing the linear volume pots for audio taper.

Pics at 11.

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