Delta pulse sniffer xr71 Problem

[Chamath]

Dear All,

I made a new search coil again and tested it today. Same results. I can't find anything bigger than 30cm even 45cm high.

This time I wrapped 14 rounds of 0.5mm wire, making the search coil 58cm in diameter.

Since there is 2.4ohm in the search coil, the fet heats up too much

Even if everything is correct, why is this device not working?

[GeoMax]

Hi,

yes, the coil data table is also distributed together with the clone PI. But this is a general purpose coil data table which is valid for the most PI detectors.

[GeoMax]

Where is your heatsink? In the picture I can not see one. Maybe if the Fet gets to hot because the TX pulse is too long or a heatsink is missing too. How long is your TX pulse in uS?

[Chamath]

Where is your heatsink? In the picture I can not see one. Maybe if the Fet gets to hot because the TX pulse is too long or a heatsink is missing too. How long is your TX pulse in uS?

I have not put a heatsink. I have seen many persons made. There is already one for sale on ebay, none of them have a heatsink

Pictured below is the device for sale on ebay

[GeoMax]

Do you have oscilloscope screen shots of the TX and RX impulse? And the timing? Maybe there is something wrong.

[GeoMax]

On which particular schematic diagram is your PCB based of? Can you upload thei schematic here?

[Chamath]

On which particular schematic diagram is your PCB based of? Can you upload thei schematic here?

only i have pcb .I just got it using internet.

[Chamath]

Do you have oscilloscope screen shots of the TX and RX impulse? And the timing? Maybe there is something wrong.

I don't have oscilloscope

[Chamath]

On which particular schematic diagram is your PCB based of? Can you upload thei schematic here?

I think there is something here that I can't fix.. Can you give me a correct pcb?

I don't know much about electronics. Can I get the pcb in the schematic you provided?

[Chamath]

Hi Chamath,

in 2005/6 I made the Delta Pulse based on the Delta Pulse schematic. I followed very closely the diagram and the circuit worked fine at the first time. There was no error in it. Of course I made my own PCB.
I did not used one of the "ready made" PCB's which were floating around the Internet.

Here is the circuit of the Delta Pulse I used for my PCB.

As you say, I can create a new pcb through this schematic. Before that, can you tell me whether it is sensitive to gold. How much depth under the ground can be tested with this?

What is the difference between the one I made and this one?

[mollax]

did you connect the two A points on the pcb

[Chamath]

did you connect the two A points on the pcb

yes

My unit is working. The problem is about depth.I Need to increase the search depth here. It seems that there is a change in components values here . that one is my idea

[kt315]

no change in components values. first circuit is sure right. mean oldest.

1. retune on standart 100Hz frequency and DO NOT TRY to change it.
2. delete all 'mods' you made/found in WWW.

[Chamath]

no change in components values. first circuit is sure right. mean oldest.

1. retune on standart 100Hz frequency and DO NOT TRY to change it.
2. delete all 'mods' you made/found in WWW.

Is this method wrong according to yours detais?

[Chamath]

Is this method wrong according to yours detais?

The person who posted this article showed a video showing that he can detect a gold ring at a distance of 20cm.. I can only detect it at a distance of 4cm.