Impulse 2

[Tim]

I was browsing Ebay the other day and came across this. It was a good price so ordered one for the hell of it.
A search here seems to show no mention of this detector.
Any background info appreciated.

[Tim]

These are finally back on Ebay if anyone else is interested. Mine's still sitting in the box...

[Qiaozhi]

These are finally back on Ebay if anyone else is interested. Mine's still sitting in the box...

I've ordered one, so we'll see what it can do.
By the way, there's only one left!
https://www.ebay.co.uk/itm/Metal-det...gAAOSwY~VZc5UY

[kt315]

- Pulse Width
- Delay

uff... they had learned something... i waste a time not intentionally.

[Tim]

You're the man to pick its brains George. I asked the seller about delay/width settings and relevance of numbers. The settings go from 1-999, lowest is least usecs, but can only be applied to speed of coil available.
The seller is quite amicable, so I wish him well.

[kt315]

i will call him here. why not?

[bernte_one]

last one sold

[kt315]

last one??? he again https://www.ebay.com/itm/Metal-detec...gAAOSwY~VZc5UY

[Tibuck19]

last one??? he again https://www.ebay.com/itm/Metal-detec...gAAOSwY~VZc5UY

Could this make a useful pinpointer ? Edit: nevermind lol 12V system for a pin pointer is to big.

[Qiaozhi]

I've ordered one, so we'll see what it can do.
By the way, there's only one left!
https://www.ebay.co.uk/itm/Metal-det...gAAOSwY~VZc5UY

It's arrived!
All the way from Kazakhstan. The postman tried to deliver it 2 days ago, but unfortunately I was out. It wasn't actually due to arrive until May 10th.

Connected a test coil and a 12V power source. Works a treat!
The main PCB is very small at 45mm x 55mm, and is a combination of SMD and through-hole. The MOSFET is an IRF740, and the PIC is a 16FL1825 with no external crystal.
There's an onboard 470R damping resistor, and a series resistor of 10R. The preamp is a TL072. I'll investigate some more later.

The menu system is controlled by 3 tactile buttons. Simple to use. As you'd expect though, the sensitivity is not startling, but better than I was expecting. It's probably overkill for a pinpointer since it has a graphical display.

[kt315]

more nothing from ICs? koschej-clone has to have 4066.

[KingJL]

It's arrived!
All the way from Kazakhstan. The postman tried to deliver it 2 days ago, but unfortunately I was out. It wasn't actually due to arrive until May 10th.

Connected a test coil and a 12V power source. Works a treat!
The main PCB is very small at 45mm x 55mm, and is a combination of SMD and through-hole. The MOSFET is an IRF740, and the PIC is a 16FL1825 with no external crystal.
There's an onboard 470R damping resistor, and a series resistor of 10R. The preamp is a TL072. I'll investigate some more later.

The menu system is controlled by 3 tactile buttons. Simple to use. As you'd expect though, the sensitivity is not startling, but better than I was expecting. It's probably overkill for a pinpointer since it has a graphical display.

Qiaozhi,
Is there any relation of this "Impulse 2" and the original Fisher Impulse designed by by Dave J?

[Qiaozhi]

Qiaozhi,
Is there any relation of this "Impulse 2" and the original Fisher Impulse designed by by Dave J?

No relationship at all. This Impulse 2 is just a simple PIC-based PI using direct sampling with a built-in 10-bit ADC. It has quite a nice menu system and a clear display. The sensitivity is good for what it is, but Surf-PI, Geotech Baracuda and MPP will beat it hands down.

I've just been measuring the TX pulse rate, and it's 175pps. Also, I mistakenly said earlier that there's a 10R resistor in series with the MOSFET, but in fact there is no series resistor. The 10R appears to be part of the supply to the transmitter circuit, along with a 1500uF capacitor.

One more thing ... the graphical display is a Nokia 5110 LCD (84 x 48, 4032 pixels).

[KingJL]

No relationship at all. This Impulse 2 is just a simple PIC-based PI using direct sampling with a built-in 10-bit ADC. It has quite a nice menu system and a clear display. The sensitivity is good for what it is, but Surf-PI, Geotech Baracuda and MPP will beat it hands down.

I've just been measuring the TX pulse rate, and it's 175pps. Also, I mistakenly said earlier that there's a 10R resistor in series with the MOSFET, but in fact there is no series resistor. The 10R appears to be part of the supply to the transmitter circuit, along with a 1500uF capacitor.

One more thing ... the graphical display is a Nokia 5110 LCD (84 x 48, 4032 pixels).

Thanks Qiaozhi.

[Tim]

Nokia screen. That's great ingenuity. Due to my health mine is still sitting in the box. It would be good to now how this goes with fastest feasible coil and shortest workable delay, as there are many adjustments available.
Still, this is a very easy and cost effective hobby build.

Thanks Qiaozhi.