ATiny-4

[Geo]

Hi 1843.
Now i have better results. With the coil of DP (1000uH) i detect a soda can at 80cm, a 2Euro coin at 30cm, and a 50 Euro-cents at 28cm, with the sample delay at 30us.
Today i will try to change the gain of the preamplifier and to put a trimer for null the offset voltage. Also i would like to construct a coil a NormanB show at PIU threa. I believe that i will gain more depth with a coil that match to the detector. Have you tried different coils to your minipulse? and did you found difference at the total performance of the detector????
Also i want from the other specialists here to tell me who is the difference if i will use IGBT transistor as the schematic show. Now i use a IRF840
Regards

[1843]

Hi Geo,

I am not an electronic expert...But my opinion is that the coil signal is the voltage source not the first resistor and zener...
The 100us second pulse is wrong... at least should be 500us! ATiny-4 is a deep seeking PI.

Regards

[Geo]

Hi Geo,

I think that its gain is 540 ( 560K/470+560).
[ATTACH]4330[/ATTACH]
Minediver detects the coin with 60us sample delay. it is good. second sample is 500us for Minediver.

Regards

Hi 1843
Because there is the diode zener, the first resistor with coil and zener are as a voltage source, so the gain is 560k/560r.
This is my opinion , so i wait the opinion and from other guys.
At ATtiny second sample is 100us after the pulse of first sample. I am afraid that this maybe to produce problems at the performance of the detector.
Regards

[1843]

Hi Geo,

I think that its gain is 540 ( 560K/470+560).

Minediver detects the coin with 60us sample delay. it is good. second sample is 500us for Minediver.

Regards

[Geo]

Hi 1843.
I will check the output of 3120 and i write to you.
About results....
Also results of your Minedriver2 are not good.
I say this because Delta Pulse with less gain and less power has better results. At coins the DP detect a 2Euro at 28...30cm with a 25 cm coil.
So where is the problem at PulseDetector Machines????
I wait from ATtiny4 to detect a 2euro coin at bigger distance than 30 cm.
The gain of preamplifier is x1000 (560k/560R).
Slowly - slowly we will make it
Regards

[1843]

HI Geo,

What is the output voltage of the HCPL? If you limited it to under 20V, it causes no ploblem.
Your coil is not good for this PI, You should use a 26cm coil with 45turns of 0.7mm wire or increase the preamp gain to 1000.
My Minediver-2 can detect a soda can at 65cm. A 2cm coin at 22cm.
Regards

[Geo]

Hi. I think that it is better to write here the problems of the ATtiny4 so some other time to know where to looking for it.
I changed the coil and with a very critical regulate of the gain, TRS and Delay i have better results but not good.
With a coil of 25 cm diameter (400uH, 0k5...1k...2k damping resistor) i detect
a 2Euro coin at 20cm max
a soda can at 50cm max.
I use a IRF840 and not the IGBT BUP213. Can someone tell me if this is a problem and why????
The peak pulse voltage is 500V
The power suplly is 21V
Any idea??
Regards

[Geo]

Thanks Oscar.
Regards

[Oscar]

Hi Geo,

The person who I did talk was from Pulsdetector Forum. His name is Norman and he has been very helpful. He said the best cable for 260mm coil would be
LIYV (14x0.15) with cross-sectional diameter of 0.25 square meter.

I have contacted a couple of Litz wire manufacturers and I hope to receive some reply soon. Stay tuned.

Regards,

Oscar

[Geo]

Hi Oscar.
Does your friend said you about the sensitivity of ATiny4???
If we will use a coil of 50cm or a square 1x1 m then we don't need LIYV wire.
Regards

[Oscar]

Hi Geo,

I did talk to one person who has already build Atiny_4 project and he told me to use the recommended cable whose specifications are at pulsdetector.com website. He said that the best cable is "LIYV, 0.25mm^2, LIY= Litz, V= tin-plated". As he has already got experience with making this detecctor, I personally believe, we need to follow other people experiences so that we can obtain best results.

Regards,

Oscar

[Geo]

Hi Oscar.
A hi Q coil is needing for sample with small delay. But for delay >= 20us a coil with normal one clone wire must be ok. I don't know at Atiny4 who is the sample delay, so you can make a normal coil at first and if you will see that the coil can't response at the programmable delay then you can construct a new one with linz wire.
Regards

[Oscar]

Hi Geo,

No problem. I will share everything with this forum because that's how people can benefit from each other.

I am still deciding which project to build (either Atiny_4 or Miner_4) as I like Miner as well which has discrimination capabilities. I might build both of them.

It will take me 2 weeks to get all components here as I need to go to few different suppliers (I am working full-time and study part-time). At this time, the only difficulty for me is to get the recommended cable from right supplier. I need to contact my cousin in Germany to get cable for me as I can not find the recommended cable here. I think the coil is very important for best sensitivity and high Q.

Regards,

Oscar

[Geo]

Hi all

I want to build ATiny_4 and I have no problem with getting electronic components here. For me, there are two things that I want to get more information. It is the coil and the battery which is using a lot of power, nevertheless powerful.

I've found this Litz calculator on the web which seems to me, it is flexible and handy for other coil configurations.

http://electronic-components.globalspec.com/specsearch/searchform/electrical_electronic_components/wires_cables/litz_wire

Regards,

Asghar

Hi Oscar.
I believe that you will finish the ATiny4 sooner than me.
So please i want to tell me any problem of this detector or everything about its sensitivity and behavior.
Regards

[Oscar]

Thanks Geo,

I am now clear about the cable specifications

Oscar