Hello, recently ive found a nice resource site (dogstar.dantimax.dk) , and wanted to start building this nice phono tube preamp.
However , I cannot understand in the schematic , just right of the 12AT7 tube, there are 3 symbols, called NE2 vr101-201.
Can you explain me what is this NE2 symbol ? Thank you !
At risk of making it too 'modern' you could replace them with 82V Zener diodes but do not bypass them completely. They are used as voltage regulators but be careful because they do change characteristics after a lot of use.