The Redmere Soloist
Channel 2 Schematics and Layouts
IMPORTANT: These drawing and notes are provided for interest only and are not guaranteed to be accurate. Use at your own risk and discretion. The equipment shown contains lethal mains voltages and should only be worked on by people with suitable training and experience. Schematics and layouts are typical but will vary.
Channel 2 Schematics and Layouts
The BF244B FET is obsolete and it's getting harder to find current production through-hole devices. Even the BF256B mentioned as a replacement in one of the drawings below has now gone out of production. Since this application is in the signal path rather than used as a switch, it might be best to try and source an original part.
One new device that might do the job is the J211 D74Z from ON Semicoductor/Fairchild if you swap the Source and Gate pins around. Mouser part number is 512-J211_D74Z.
Pin-out mismatch between old and new components is a bit of a problem right through the amp, as a lot of 1970s semi's seemed to favour a (now uncommon) layout used by Japanese manufacturers at the time.
PRINTING
Wix (bless 'em 😖) have changed their image format - again - to avif just to make them awkward to print. Unless you want to buy a converter, the easiest way to make a hard copy is:
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Left click when the magnifying glass icon appears and wait for the picture to clear.
(On a touch screen, tap on the image). This will display a higher res file. -
Right click and 'save image as' to somewhere as an avif file.
(On a touch screen, touch and hold down to view the menu) -
Upload the saved file to your Google Drive.
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Open the file and use the print menu to make a hard copy or save as a pdf.
Channel 2 Schematic. S-3-1 Boards
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Channel 2 PCB Layout. S-3-1 Boards
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Channel 2 Schematic. S-3-2 Boards
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Channel 2 PCB Layout. S-3-2 Boards
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