Surf pi detector-MOD

[GeoMax]

Okay,

Have you ever tried testing a 10k logarithmic potentiometer instead of a standard 10k linear potentiometer? Maybe that's better for you.

[algan]

I will try it with logarithmic, but with linear it depends a lot on how the threshold is set. With a 28 cm antenna, minimum threshold 10 cents Bulgarian coin with a diameter of 18.5 mm, it detects at 20 cm, with an increased threshold 25 cm, but when it is in a position between the increased and minimum threshold is 10 cm, it detects at 30 cm.

[GeoMax]

Hi Algan

So, if you use a logarithmic potentiometer, you "stretch" the control's adjustment range slightly to make it easier to adjust between the minimum and maximum ranges. See the green curve in the diagram.

[pulseinduction]

Hello! Can you please tell me why my Surf PI makes a false beep when I move it in the air, but if I don’t move it, it stops beeping.

[Qiaozhi]

Hello! Can you please tell me why my Surf PI makes a false beep when I move it in the air, but if I don’t move it, it stops beeping.

It's probably responding to the Earth's magnetic field, which means that the EFE (Earth Field Elimination) circuit is not working correctly.

[pulseinduction]

Hello,
Please tell me why the Surf PI decreases its detection distance outside. I tested it indoors at a temperature of 20°C and it detects a 1-cent coin at 36 cm. When I go outside at 3°C, after approximately one minute the detection distance drops to 15 cm. When I return indoors and test it immediately, it still detects at only 15 cm, but after about 10 minutes it goes back to detecting the coin at 36 cm. Why does this happen and what should I adjust so it detects at the same distance as indoors?

[Ruben2000]

Has anyone seen this video?
https://www.youtube.com/watch?v=EWwWE3YpEqA

[GeoMax]

Has anyone seen this video?
https://www.youtube.com/watch?v=EWwWE3YpEqA

Hi Ruben2000,

I saw this video a few years ago. It offers beginners a good overview of how to build a metal detector and what to pay attention to. The video in the link you posted is part 2. There's also a part 1, which is also interesting. See below.

Part 1: HOW TO BUILD THE GOLDFINDER XTR METAL DETECTOR - PART 1
Part 2: HOW TO BUILD THE GOLDFINDER XTR METAL DETECTOR COILS - PART2

[Ruben2000]

Yes, this video was very interesting to me. Several months ago, I finished assembling the Surfmaster PI, and the detection range was very low, just like in the video I shared, so I set it aside. Now I know what I need to do to increase the range, based on the video. Also, I'd like it to be able to detect gold nuggets. If anyone knows what else I can do to make the Surfmaster PI detect gold nuggets, I would be very grateful.

[scs-bg]

In practice, pulse detectors are no better than inductive balance detectors. The advantage of pulse detectors is that they are easy to make.

[Ruben2000]

One question: Are IB detectors and VLF detectors the same thing?

[Qiaozhi]

One question: Are IB detectors and VLF detectors the same thing?

No, they're not the same thing.

IB is an acronym for induction balance. It refers to the configuration of the coils inside the search head. The coils are arranged such that there is minimal pickup between the windings.
VLF is an acronym for very low frequency. This refers to detectors that operate between 3kHz and 30kHz.

A PI detector can also use an IB coil, and even though a typical PI may operate at 1000 pps, this is not classed as VLF.

[kt315]

One question: Are IB detectors and VLF detectors the same thing?

the same. IB is early title, VLF is late, more modern.

[Ruben2000]

No, they're not the same thing.

IB is an acronym for induction balance. It refers to the configuration of the coils inside the search head. The coils are arranged such that there is minimal pickup between the windings.
VLF is an acronym for very low frequency. This refers to detectors that operate between 3kHz and 30kHz.

A PI detector can also use an IB coil, and even though a typical PI may operate at 1000 pps, this is not classed as VLF.

So, is the SMW an IB detector or a VLF detector?

[Ruben2000]

the same. IB is early title, VLF is late, more modern.

I agree with KT because in both cases the coils have to be balanced.