Minelab detector repairs and info

[detectormods]

This may be useful to some of the members here in regards to the repair of the Minelab P.I detectors. I started to put up video?s on youtube to show various faults that can occur on the ML detectors and how to diagnose and repair, i have been mucking around with detectors since 1980 so i have seen a few, have spent the last 25 years or more repairing and modifying SD GP GPX series detectors. Anyway, the link to my detector UTube is https://youtube.com/@DetectorMods. If you want specific info i can provide it as under education, if you require part numbers i can give my opinion on what the component is? as well know, ML does not want any of the information about their detectors getting into the wrong hands and they have no problem starting legal action to protect their business, this is the reason why i am not publishing schematics or design info, but i am protected by the Hague conventions to having an opinion. So most of my answers are not definite, they are all based on opinion.

[Orbit]

This may be useful to some of the members here in regards to the repair of the Minelab P.I detectors. I started to put up video?s on youtube to show various faults that can occur on the ML detectors and how to diagnose and repair, i have been mucking around with detectors since 1980 so i have seen a few, have spent the last 25 years or more repairing and modifying SD GP GPX series detectors. Anyway, the link to my detector UTube is https://youtube.com/@DetectorMods. If you want specific info i can provide it as under education, if you require part numbers i can give my opinion on what the component is? as well know, ML does not want any of the information about their detectors getting into the wrong hands and they have no problem starting legal action to protect their business, this is the reason why i am not publishing schematics or design info, but i am protected by the Hague conventions to having an opinion. So most of my answers are not definite, they are all based on opinion.

This has shown that you are a good person!

[ionut_mtb]

This may be useful to some of the members here in regards to the repair of the Minelab P.I detectors. I started to put up video?s on youtube to show various faults that can occur on the ML detectors and how to diagnose and repair, i have been mucking around with detectors since 1980 so i have seen a few, have spent the last 25 years or more repairing and modifying SD GP GPX series detectors. Anyway, the link to my detector UTube is https://youtube.com/@DetectorMods. If you want specific info i can provide it as under education, if you require part numbers i can give my opinion on what the component is? as well know, ML does not want any of the information about their detectors getting into the wrong hands and they have no problem starting legal action to protect their business, this is the reason why i am not publishing schematics or design info, but i am protected by the Hague conventions to having an opinion. So most of my answers are not definite, they are all based on opinion.

Thanks. I’m already following you!

[eclipse]

What's your opinion on the GPX4000 vs GPX4500 vs GPX5000 /performance wise, construction, noise/ I know that the last 2 share almost identical design while the GPX4000 is quite different, perhaps it punches a bit less in real world?
Is the GPX 4000 closer to the GP3500 rather than the 4500/5000 ?

I have 3500, but I haven't opened it up, as well as the 4500/5000, but it's in pristine condition I really hate to open it and put it next to the 4500/5000 on the bench.

[hooby life]

This may be useful to some of the members here in regards to the repair of the Minelab P.I detectors. I started to put up video?s on youtube to show various faults that can occur on the ML detectors and how to diagnose and repair, i have been mucking around with detectors since 1980 so i have seen a few, have spent the last 25 years or more repairing and modifying SD GP GPX series detectors. Anyway, the link to my detector UTube is https://youtube.com/@DetectorMods. If you want specific info i can provide it as under education, if you require part numbers i can give my opinion on what the component is? as well know, ML does not want any of the information about their detectors getting into the wrong hands and they have no problem starting legal action to protect their business, this is the reason why i am not publishing schematics or design info, but i am protected by the Hague conventions to having an opinion. So most of my answers are not definite, they are all based on opinion.

Yes, I have watched all of your videos. I own a gpx 4500, some transistors burned out, and it gives a depth of no more than 10 cm on large objects. I wanted to repair, but I do not know the name of the transistors. Here are some of their pictures for you .



Regards part names pls thanks

[detectormods]

If you watch the video i point out the N channel mosfets and the bav99 protection diodes, just remember that SD GP detectors input fets are n channel and then p channel and with gpx the fets are both n channel, my take is that the p channel had too much intrinsic capacitance for the faster switching time for enhance and fine gold. Did you see my video on the floating front end? Gets rid of the board based gate drive with associated noise injection and gate modulation.

[hooby life]

If you watch the video i point out the N channel mosfets and the bav99 protection diodes, just remember that SD GP detectors input fets are n channel and then p channel and with gpx the fets are both n channel, my take is that the p channel had too much intrinsic capacitance for the faster switching time for enhance and fine gold. Did you see my video on the floating front end? Gets rid of the board based gate drive with associated noise injection and gate modulation.

Thank you so the doid are bav99 and the mosfet are 2n7002 .did there are any replacment for ?

[detectormods]

The detector works with BAV99 removed, look up component specification and find similar.

[hooby life]

The detector works with BAV99 removed, look up component specification and find similar.

Thank you what about mosfet 2n7002 any replacment work fine?

[hooby life]

What about 2n7000?

[kt315]

What about 2n7000?

ask me what about soviet KT315.

[Carl-NC]

What about 2n7000?

Same part but thru-hole.

[hooby life]

Thanks so much i found a k72 in trash i will try it and see

[hooby life]

The detector works with BAV99 removed, look up component specification and find similar.

Where can jumber anode/gathod bav99 due to the damage of the welding place ?


Sorry for my english am biginer in electronics

[kadir6141]

Bss84?