UK Vintage Radio Repair and Restoration Discussion Forum

This is something I should know, but never managed to pin down, and that's the procedure for "rocking" or "rocking-in" during receiver alignment.

Assume a standard MW/LW receiver with trimmers at the HF end of each band, and padders or adjustable inductors at the LF end of each band. At which end of the band is rocking effective?

By "rocking" I mean the gentle peaking of the test signal at the calibration point by alternatively tweaking the main tuning with the associated trimmer/padder for maximum signal, even if this moves the signal off the calibration point. And if it does, adjustments at the other end should bring it back. (All done because tracking is not linear, particularly if the LO and antenna tuning gang has identical sections which is usually the case.)

I'm minded to think this should be generally done at the LF end, and any tuning discrepancy corrected at the HF end with the trimmer - if there is one. Of course some sets only have preset adjustments at one end of the band in which case this is a moot point. Or is it...?

Thanks.

Ian

PS: Incidentally, this was discussed by Dick and Smithy from Radio and Electronics Constructor in the 70s, but of course their topics are not indexed anywhere so will take ages to locate!