We’ve two of these sets with the same problem, optimum
sound and vision cannot be tuned in together, though both
the sound and the picture are perfect. The sets are used on
625 lines only.
First ensure that the contrast is set well down, consistent
with an acceptable picture. Tune in a test card, adjusting for
best resolution of the frequency gratings. Then tune the
sound discriminator coils 2L27/8/9 (two cores) for buzz
free sound, resetting the balance control 2RV2 if necessary.
If further adjustment is required, tune the sound take -off