04-18-2016, 02:30 PM
The Mirage PI that I build, now and then I get a question why its so good finding gold and not silver. Why is it not deeper than general purpose PI's finding silver vs. gold?
Sometimes its tough explaining it in simple terms when asking what kind of PI should I buy. I found a report by White's, copied and pasted here the main reason
The pulse repetition rate (transmit frequency) of a typical PI is about 100 pulses per second. Models have been produced from a low of 22 pulses per second to a high of several thousand pulses per second. Lower frequencies usually mean greater transmit power. The transmit current flows for a much long time per pulse, however, there are fewer pulses per second. Higher frequencies usually mean a shorter transmit pulse and less power however, there are more transmit pulses per second.
Lower frequencies tend to achieve greater depth and greater sensitivity to items made from silver however, less sensitive to nickel, and gold alloys. They typically have a very slow target response, which requires a very slow coil sweep speed.
The Mirage PI is a high frequency detector-
Higher frequencies are more sensitive to nickel and gold alloys however, less sensitive to silver. They may not penetrate quite as deep as the lower frequency models regarding silver however, can be used with a faster coil sweep speed. Higher frequency models are generally more productive for treasure hunting because the faster sweep speed allows more area to be searched in a given time, and they are more sensitive to the ultimate beach find, gold jewelry.
There are several more calibration settings that also make it more sensitive to very small gold nuggets and jewelry that's Pulse Delay and Pulse Width.
Sweep speed of the Mirage can be a small snail crawl or faster VLF pace. With the SAT control can be used as a motion recovery control. Set at 75%, you can swing like a normal VLF machine.
Have to get out and use it more, tired of digging the tiny foil bits with the VLF. I can more or less tune the foil out and still find the small gold.
Sometimes its tough explaining it in simple terms when asking what kind of PI should I buy. I found a report by White's, copied and pasted here the main reason
The pulse repetition rate (transmit frequency) of a typical PI is about 100 pulses per second. Models have been produced from a low of 22 pulses per second to a high of several thousand pulses per second. Lower frequencies usually mean greater transmit power. The transmit current flows for a much long time per pulse, however, there are fewer pulses per second. Higher frequencies usually mean a shorter transmit pulse and less power however, there are more transmit pulses per second.
Lower frequencies tend to achieve greater depth and greater sensitivity to items made from silver however, less sensitive to nickel, and gold alloys. They typically have a very slow target response, which requires a very slow coil sweep speed.
The Mirage PI is a high frequency detector-
Higher frequencies are more sensitive to nickel and gold alloys however, less sensitive to silver. They may not penetrate quite as deep as the lower frequency models regarding silver however, can be used with a faster coil sweep speed. Higher frequency models are generally more productive for treasure hunting because the faster sweep speed allows more area to be searched in a given time, and they are more sensitive to the ultimate beach find, gold jewelry.
There are several more calibration settings that also make it more sensitive to very small gold nuggets and jewelry that's Pulse Delay and Pulse Width.
Sweep speed of the Mirage can be a small snail crawl or faster VLF pace. With the SAT control can be used as a motion recovery control. Set at 75%, you can swing like a normal VLF machine.
Have to get out and use it more, tired of digging the tiny foil bits with the VLF. I can more or less tune the foil out and still find the small gold.
