01-26-2014, 12:28 AM
Sometimes the direction of winding does matter in an antenna or RF interstage coil. In these instances there is a combination of capacitive and inductive coupling between the primary and secondary windings.
This is done to increase signal transfer at the high end of the band where the freq response tends to roll off. Sometimes there is an actual coupling cap, other times there is a few extra turns of unterminated winding connected to the primary in close proximity to the secondary. If the winding is done in the wrong direction, the capacitive coupling will be out of phase with the inductive component, resulting in reduced gain at the high end of the tuning range.
So in general, it is always better to note the direction of winding when removing the old coil and rewind in the same direction.
This is done to increase signal transfer at the high end of the band where the freq response tends to roll off. Sometimes there is an actual coupling cap, other times there is a few extra turns of unterminated winding connected to the primary in close proximity to the secondary. If the winding is done in the wrong direction, the capacitive coupling will be out of phase with the inductive component, resulting in reduced gain at the high end of the tuning range.
So in general, it is always better to note the direction of winding when removing the old coil and rewind in the same direction.