I have an old tube FM tuner. I want to convert it to a stereo tuner. How to adapt the decoder?
In principle, adaptation is possible if the pilot signal passes through the circuits, which is not the case in most cases. The de-emphasis circuit that blocks the signal must also be removed. If the 38 kHz signal is obtained at the detector (discriminator), it is from this point that it must be removed to be applied to the decoder circuit. The chances of success without affecting sound quality are not high.
