qoute from eric:
Hi Mark,
Pendants and chains are difficult to detect in a saltwater beach environment. This is because the saltwater itself gives a large signal and the pulse delay has to be limited so that this effect is minimised. In the PI Pro the delay is 15uS, and you cannot get much shorter than this without a lot of interference from the water in the sand. Even at 10uS, which my Aquasearch and Goldquest run at, many chains are not detectable, unless the links are chunky. If you go into the water with the Aquasearch, you need to adjust the delay back to around 15uS, otherwise waves and swell give changes in the audio threshold.
A freshwater beach would be different, or even in dry sand, and you could use pulse delays down to 5uS and pick up a lot more chains and pendants. However, I don't know of any commercial PI detectors that run at this, as the coil and electronic design becomes more critical.
A smaller coil on the PI Pro would not help much, as it is the pulse delay that is the limiting factor.
MR BILL SAYS PULSE CONTROL TAKEN OUT OF PI PRO AND REPLACED WITH GAIN CONTROL
Steve
The reason of the complaint on the new "Pro" version is because Whites choose to remove the pulse delay control, and replace it with a "gain" control. This playing around with the circuit has a side affect of making it unstable in certain hunting conditions.
The pulse delay control is still needed.
Mr.bill
Hi Mark,
Pendants and chains are difficult to detect in a saltwater beach environment. This is because the saltwater itself gives a large signal and the pulse delay has to be limited so that this effect is minimised. In the PI Pro the delay is 15uS, and you cannot get much shorter than this without a lot of interference from the water in the sand. Even at 10uS, which my Aquasearch and Goldquest run at, many chains are not detectable, unless the links are chunky. If you go into the water with the Aquasearch, you need to adjust the delay back to around 15uS, otherwise waves and swell give changes in the audio threshold.
A freshwater beach would be different, or even in dry sand, and you could use pulse delays down to 5uS and pick up a lot more chains and pendants. However, I don't know of any commercial PI detectors that run at this, as the coil and electronic design becomes more critical.
A smaller coil on the PI Pro would not help much, as it is the pulse delay that is the limiting factor.
MR BILL SAYS PULSE CONTROL TAKEN OUT OF PI PRO AND REPLACED WITH GAIN CONTROL
Steve
The reason of the complaint on the new "Pro" version is because Whites choose to remove the pulse delay control, and replace it with a "gain" control. This playing around with the circuit has a side affect of making it unstable in certain hunting conditions.
The pulse delay control is still needed.
Mr.bill