why makes Ferrite a Phase Shift to the left?

[lektor]

Hello! I have for my old vfl detector new DD (10 inch) Coilswound with the values TX 3.85 mH and 4,1mH Frequency 8.5 kHz.the problem: it is not Ground Balancing adjustments possible, becauseFerrite a Phase Shift to the left. ask: why produces Ferrite ever aPhase Shift? I hope the translation is understandable.

[Skippy]

All regular ferrites produce zero degrees phase angle, example: that from a Medium Wave (1MHz) radio rod. There are some exotic ferrites that are intended for lower frequency use, like 20KHz or lower, it may be that these have a shift that is measureable, but they are rare.

[lektor]

thanks for the answer. but why are the tgsl ferrite cores with my detector and my delta pulse (PI) declined?

[Skippy]

I cannot answer, I know nothing about the TGSL detector.
Hopefully someone else can help.