chance pi build

[baum7154]

Thank you WM6. There are some other generic detector mods also in this thread, such as implementing the 3 piece take down boom offered by Whites. Making this change from my original PVC boom reduced the weight of the detector by 1pound, 1ounce, a significant weight reduction and improved pack-ability for the back country.

Regards,

Dan

[dantech]

Hi,
I have renewed Chance PI project and there is v162 firmware at the moment.
Some small hardware modifications are necessary.
The firmware was rebuilt and Chance PI is now very simple, powerfull and stable construction.
Do not overclock CPU because of very sophisticated timings, alghorythms and difficult metal selecting process.

Important!
Because of next british betrayal and Brexit The Britons cannot use my Chance PI firmware release.
The young Poles will not forget you the start and the end of 2nd World War...
-----------------------------------------------------------------------------------------------

Here are polish threads:
http://wloczykij-forumposzukiwaczy.c...=5668&start=60
http://www.exploracja.cyberdusk.pl/phpbb2/viewtopic.php?f=45&t=19909

https://www.youtube.com/watch?v=j1RlKnGBiow

[Qiaozhi]

Important!
Because of next british betrayal and Brexit The Britons cannot use my Chance PI firmware release.
The young Poles will not forget you the start and the end of 2nd World War...

That's a very broad statement. What about the 48.1% who voted to remain in the EU, and the 4,146,160 people who signed a parliamentary petition for a second EU referendum?

[dantech]

What about fact they leave us alone at the start and the end of 2nd WW?
They forget who discovered how Enigma works or who was fighting for their country? Belive me we have 1000 other reasons to use those words
Someone know who was Rejewski and Zygalski?

I decide that The Britons cannot use my release

[baum7154]

Hello Dantech,

I had a true friend of 30 years who was a Polish military officer in the armored units of Poland when it was taken over. I learned much from him about the war before he passed away here in the US at the age of 89 nearly 6 years ago. His 95th birthday would have been on Sept. 12th. He was a kind, wise, and educated gentleman and he is greatly missed.

I am very interested in the details and changes in your new firmware release. Would you please explain what changes you have made?
Have you built the original Chance PI and used it in the field?

In some of my earlier posts of this thread I made some suggestions for firmware upgrades after working with this modified detector for several years. One was to allow GUARD INTERVAL lower limit to be set down to a setting of about '4' or '5'. Another was to allow the sample window width to be variable instead of a fixed 12.5 us. A third was to have some control of the pulse rate and duration. A fourth was to reduce the audio detection frequency of the metals at the right end of the scale.

Regards,

Dan

[daverave]

Hi,
I have renewed Chance PI project and there is v162 firmware at the moment.
Some small hardware modifications are necessary.
The firmware was rebuilt and Chance PI is now very simple, powerfull and stable construction.
Do not overclock CPU because of very sophisticated timings, alghorythms and difficult metal selecting process.

Important!
Because of next british betrayal and Brexit The Britons cannot use my Chance PI firmware release.
The young Poles will not forget you the start and the end of 2nd World War...
-----------------------------------------------------------------------------------------------

Here are polish threads:
http://wloczykij-forumposzukiwaczy.c...=5668&start=60
http://www.exploracja.cyberdusk.pl/phpbb2/viewtopic.php?f=45&t=19909

https://www.youtube.com/watch?v=j1RlKnGBiow

Not because i want your new firmware release,but you need to get your facts right,you cannot blame british people for what happened concerning brexit,cant you see its all a big fix by the people in power !!! european people in my view have been used as pawns by the powers that be !!!!! its all hollywood believe me !!! personally i like a multi cultural society cause in reality there should be no borders and people from whatever country should be able to live wherever they they desire,the people of the uk were not the one's who decided we should leave the EU but people in high places with hidden agenda's.

[dantech]

OK. This is Chance, Last chance... Let them use it

Later I shall write something more about new release

[dantech]

Keep in mind that genaral idea comes from Fandy/Russia and my release is continuation his work.
In the attached archive you can find changelog.txt. I think the easiest way is to use google translator. There is no common sense to rewrite it in english.
There I have described every change.

In a few words:
- full metal masking
- stability
- full signal masking
- easy use
- 16 step of audio frequency depending on vdi
- audio frequency in the limited (audible) range as described in the changelog.txt
- gui and menu rebuild
- new metal masking way
- quick and accurate auto ground balancing giving optimal sensitivity
- quick keyboard response


The only one part on board that could be adjusted is R9. R9 can change quality of signal edges and rathed should be verified under the oscilloscope.
You can easily feel up when R9 should be adjusted (rather less value) when hardware works like one need some time to "warm up" and vdi meter varies when object is closed to the coil.
It means that transistor does not work properly and its point shifts in the time and signal edges driving MOSFET are too "round" and not stable in the time.

Generally my hardware is little bit simpler than original hardware.

I need reports from field. I have used my release on the beach and my garden and Chance worked perfectly


Oooooppppsssss..... sorry. There is no changelog.txt inside the archive. I have added file into archive also.
Look below, use google translator

On polish threads (pointed above) I have described how to make coil and frame.
When 12V gel battery is used I suggest use 2nd schematic with additional voltage reduction (2 diodes). I do not prefere to use ICL7660 working above upper limits. Fully charged gel battery has at least 12,5V and even 13,8V. PCB (.lay6 files) inside archive are some old designs. I use it with my modifications made manually.

I have used original Chance firmware v121 but there was a few bugs. For instance whipping up when the object is in the coil range too long time. Generally the coil has to have fast response (low resistance and low capacity) because of series sophsticated pulses.
The author (Fandy/Russia) has stopped development and inspired me to develop his ideas.

We have to have in mind that ATmega8 has limited flash memory resources. At the moment I am thinking to make data transfer via RS232. Maybe CPU will be changed onto ATmega168.

[reptooyep]

I didn't know that MD has something to deal with political things. Hopefully for me, there is no frexit planned for the moment...
Thanks for your work on this project

[baum7154]

Is the shortest sample delay still set to about 9us as in the original design?

Dan

[dantech]

The delay range is 20-99 us but below 25us there is nothing interesting in signal. So there is no sense to use values below even 28us. 20us is big margin in my opinion.
In the original v121 there was hidden at least 4us additional timeshift (exactly it was the time necessary to convert signal bu ADC). In my release the time is more real now.

[dantech]

@reptooyep
There is one advantage. A few people more in the world will know who broke Enigma in fact
If you like to use metal detector you would like the true history.
Not Alan Turing but anonymous Poles: Zygalski, Rejewski and Różycki team.
Guess what where his life after war? They have died anonymously forgotten by "friends"
The cinema and popular movies lie!

The end of off topic

http://ethw.org/Milestones:First_Breaking_of_Enigma_Code_by_the_Te am_of_Polish_Cipher_Bureau,_1932-1939

[baum7154]

The delay range is 20-99 us but below 25us there is nothing interesting in signal. So there is no sense to use values below even 28us. 20us is big margin in my opinion.
In the original v121 there was hidden at least 4us additional timeshift (exactly time necessary to convert signal bu ADC). In my release the time is more real now.

__________________________________________
Thanks for the reply. I use my modified CHANCE PI with a fast 3DSS coil to detect small gold in the 1/3 to 1/2 gram range and this requires sample delays at 10us and less. It also requires that the preamp does not saturate, making detection of these small and fast targets possible.

Regards,

Dan

[dantech]

@baum7154
You say - you have
Tell me something more about 3DSS coil and your idea.


Try this one. The compiler did not report any error so in theory firmware should work well because change was not too important
Keep in mind that v163 was not tested by me at all!

Main pulse delay time range is 1-99us

[Qiaozhi]

I do not prefere to use ICL7660 working above upper limits.

You should replace the ICL7660 with an LT1054 which is pin-compatible, but has a maximum input voltage of 15V.