[Sideband]

Hi Pete. You cannot align a discriminator properly by ear. With experience you can get close but really the minimum you need is a signal generator and a multimeter (an analogue one is better). Usually one of the cores of the discriminator coil is tuned for minimum output and you need the meter to see this (this is the balance point so that the discriminator is balanced about the detected signal)....but you need to feed 10.7 Mhz in to the I.F strip at the recommended points in order to measure the minimum signal.

You could try a new EB91 in case there is a problem with one of the diodes and the discriminator won't balance anyway but ultimately you should aim at getting the FM aligned properly.


SB