Commercial DD coils usable for PI

[Teleno]

I see that most after market DD coils out there are targeting VL detectors. Apparently some of these coils contain capacitors in the casing, which is bad for PI. I have successfully used this coil with the MiniPulsePlus PI detector. It was meant for ML Safari, Explorer or E-TRAC. It doesn't appear to contain any capacitors.

Has anyone used commerical DD coils in a PI project? Please share your experiece and/or recomendations.

[Qiaozhi]

I see that most after market DD coils out there are targeting VL detectors. Apparently some of these coils contain capacitors in the casing, which is bad for PI. I have successfully used this coil with the MiniPulsePlus PI detector. It was meant for ML Safari, Explorer or E-TRAC. It doesn't appear to contain any capacitors.

Has anyone used commerical DD coils in a PI project? Please share your experiece and/or recomendations.

Is this the coil that has TX = ~580uH, and RX = ~470uH?

[Teleno]

Is this the coil that has TX = ~580uH, and RX = ~470uH?

That's the one. Tx = 580uH 1 ohm, Rx = 500uH 5.4 ohm. Works perfect but the Tx pulse needs to be extended to at least 100us.

[mschmahl]

I had tried this coil (only bigger 12"x15", but also SEF with same uh and ohm) and get it to work but only for testing. I think it is not so good balanced because it is balanced for VLF with 12 to 20 kHz. Better is to use one of the GPX coils, e.g. this one http://nuggets.at/DETECH-38x30-cm-15...X-SD-SuchSpule