01-09-2022, 12:45 PM
The only reason I can think of for winding antenna and RF coils in the original directions is that in some cases the phasing of the windings may be important. This is because certain coils may be designed with both inductive and capacitive coupling between the windings.
Some antenna coils have an extra turn or two of unterminated wire from the top of the primary wrapped around the hot end of the secondary. This wire provides a small amount of capacitive coupling to the secondary and was done to increase the signal transfer at the high end of the broadcast band where the sensitivity would tend to drop off.
So, when both windings were done in the correct direction, the current induced in the secondary is in phase with the current coupled by the capacitance and add together constructively. If one winding is done in the opposite direction, the two currents will be 180 degrees out of phase and will subtract, causing a loss of sensitivity at the high frequency end.
In any case, if possible it would make sense to try and rewind the coils exactly as they were originally.
Some antenna coils have an extra turn or two of unterminated wire from the top of the primary wrapped around the hot end of the secondary. This wire provides a small amount of capacitive coupling to the secondary and was done to increase the signal transfer at the high end of the broadcast band where the sensitivity would tend to drop off.
So, when both windings were done in the correct direction, the current induced in the secondary is in phase with the current coupled by the capacitance and add together constructively. If one winding is done in the opposite direction, the two currents will be 180 degrees out of phase and will subtract, causing a loss of sensitivity at the high frequency end.
In any case, if possible it would make sense to try and rewind the coils exactly as they were originally.
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