Impulse 2

[kt315]

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.

our first project wih ZAK was VDI (godograph) with Nokia screen. ZAK did soft, i did schematic part and pcb, - you see it here.

[qute1]

Arrived, fires up but display is FUBAR backlight but nowt else, just fiddling and it does detect with appropriate coil but cant really set anything as can't see the display!
Maybe just the pin connector but haven't had time to play yet apart from redobbing the solder joints suspect its the connector block but ....

[qute1]

Mines in transit so waiting with baited paws (and mixed metaphors) i will give an opinion when it hits the mat.

[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.

[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.

[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]

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?

[kt315]

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

[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.

[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.

[kt315]

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

[bernte_one]

last one sold

[kt315]

i will call him here. why not?

[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]

- Pulse Width
- Delay

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