I fixed a '78 Ray with a dead preamp…
Hi all. I thought you guys might be interested in a bass I recently worked on. It was a 1978 StingRay with a dead preamp.
As a tech, I’ve worked on quite a few early stingrays in the last few years, but I’ve never seen one with a dead biasing resistor before.
I ended up also replacing the current set resistor since it had drifted a long way from 1M5.
I also shifted the negative battery wire and put in a reverse polarity protection diode, to bring it up to modern standard.
Source: http://forums.ernieball.com