Coil specification for a Whites PI-1000 or PI-2000 or PI-3000 detector needed

[GeoMax]

Hello,

does someone knows the inductons or specification of the mono coil for a White Treasuremaster PI-1000, PI-2000 or PI-3000 underwater metal detector?
In one of the schematic diagrams I found the information that the coil diameter is about 11 inch and has 18 turns. Is this correct?

thanks...

[Altra]

My old notes show 200uH, 1.25 ohms. The original 11 inch coil had 18 or 19 turns

[GeoMax]

Hi,

thanks for the information. Wow 200uH only? I was guessing that the coil could have around 300 to 350uH like the most standard PI coils have.
Have you measured the 200uH inductance from your notes that time?

Thanks again...

[Altra]

Yes, I measured the inductance of more than one unit. Built around the same time period, the Garrett Xl500 pi had a coil inductance below 300uh also.

The pi1000 is simple yet tricky. It has fixed sample periods. So you need to get the coil and damping right for good sensitivity.

[GeoMax]

Hi Altra,

thanks for your reply. Yes, the samples are very much fixed and can not be changed easiely.

[GeoMax]

I have another question in regards to the coil. What wire was used to make the coil? Magnet wire, stranded litz wire or HF-litz wire?

[Altra]

I think something like stranded tin #24 or #26 gauge with pvc insulation will work just fine. Avoid using magnet wire, litz wire would be a waste on this detector.

The cable to the detector was equivalent to RG58A/U stranded coax

[GeoMax]

Thanks for your input.