I,ve run into a problem with a low level buzz from one quadrant out put, and nowhere else. It possibly could have been there from day one, as I just started using the balanced outs and it is on the neg out of one channel. It appears on the scope as an upper half of a sign wave about .5ms long and repeats every 8ms or so and is about 8mv. The only thing I used differently from the original design is BC550C and 560C for the ccs, but I have put caps across them to no avail. All my voltage readings are right on for the entire board. I have swapped supply boards, systematically replaced every component in that quadrant, reflowed every solder joint, and totally isolated the board from all input and output wiring, with no change. I'm using Kristians boards with dual regs.
Could the problem be with the higher hfe of the BCs or an inherent problem with the board layout.
The unit has always performed fine but the buzz is audible using balanced outs. I guess its actually 120hz hum.
Anybody out there seen anything like this before?
Questions or comments are definately welcomed.
Bill
Could the problem be with the higher hfe of the BCs or an inherent problem with the board layout.
The unit has always performed fine but the buzz is audible using balanced outs. I guess its actually 120hz hum.
Anybody out there seen anything like this before?
Questions or comments are definately welcomed.
Bill