Surf PI Pro

[Jeroi]

have anyone here tried the dual field coil for surf pi or is same performance like the monoloop (for example 2*150 till 180 microH in serie 15cm inner 30cm outer)

I produced just like that coil with 25 rounds and 55 rounds. The end result was 1.12mH coil which is similar inductance than these test coils usually have. So I would not except my coil behaving bad with PI circuit.

[bernte_one]

hello jim

i have finished your pcb design yesterday
works from first start

many thanks again

next days i will start to tune and change some parts
like recommended from ApBerg

i think i change: ne5534 to lt 1115, main cap value and reinforce the solder tracks to coil output

but i could need some infos to get best setting point
so if anyone can give me datas for testing points where i can set up right voltages at ic
i would be happy

have anyone here tried the dual field coil for surf pi or is same performance like the monoloop (for example 2*150 till 180 microH in serie 15cm inner 30cm outer)

regards

[terhaka]

hello ApBerg and every body
apberg thanks for the email I want it to have a direct chat with you cuase I have so many questions and also you may find in me a good friend and also as you said every body here is helping I learned many things here

[ApBerg]

very clear explanation thanks ApBerg I hope to have your email to be in touch with you any time
terhaka

Hello Terhaka,
You can mail me with the help from the Geotech Community options.. there is also my mailadres.
It is however wise to ask your questions here it the Forum, there are many friends here that now much more about detector-electronics than I do.. and that way we all learn !

Best regards.
Ap

[terhaka]

very clear explanation thanks ApBerg I hope to have your email to be in touch with you any time
terhaka

[ApBerg]

thanks ApBerg
and I have another question what is the reason of the 1000uF capacitor because when I inserted it the out put of TL071 -that I replaced the NE5534 with- was bad and By removing it the signal form TL071 becomes much better
I appreciate any help thanks
terhaka

Think you better use NE5534 or a LT1115 if you can get it.


question what is the reason of the 1000uF capacitor :

After the fet (Irf9640) is switched on, the 1000uF cap. can supply fast the needed energy to the coil, the battery's cannot give so fast the energy that is needed ..
In the time that the fet is closed the battery's refill the 1000uF cap.

Think that the 1000uF cap. is a bucket full of water, if you empty it you have in a short time plenty water, in the 'time out' it refills via a water hose.

In a PI design the tracks that are needed for the "batt-cap-coil'' circuit need to be solid and short...

Hope it is clear... or somebody can give a better explanation..

[terhaka]

thanks ApBerg
and I have another question what is the reason of the 1000uF capacitor because when I inserted it the out put of TL071 -that I replaced the NE5534 with- was bad and By removing it the signal form TL071 becomes much better
I appreciate any help thanks
terhaka

[ApBerg]

....hope not to much errors...........

Large cap 3900uF was 1000uF, for NE 5534 now LT1115.


No Sprint file , sorry ... have deleted the file.... yea ... trashbin... .....also empty..
Had made some bmp´s so not al lost, see the the zip file.

Best regards.

[ApBerg]

hello every body I am really confused I am facing a problem with the last part of the circuit (the audio part) I really want an explanation of how the last part of the circuit works
I really appreciate any help please

http://www.geotech1.com/pages/metdet/patents/US5414411.pdf

[terhaka]

hello every body I am really confused I am facing a problem with the last part of the circuit (the audio part) I really want an explanation of how the last part of the circuit works
I really appreciate any help please

[terhaka]

thanks porkluvr for the help andI am very sorry for binng late
and hello evry body I have more and more questions I replaced the NE5534 with TL071 am I have to replace any other componants
like the 1 nF capacitors

[Qiaozhi]

OOPS, Sorry I GOOFED.
They are Correct.

Damn that 60 minute editing window.

[chemelec]

I Do Not believe this board or Schematic is correct.

With the Pin Connections to the 4066, Pins 10, 11 & 12 do not pass a signal out.

Removing these IC Pins from the Socket and Jumping pins 11 & 12 Together Does appear to work Ok.

OOPS, Sorry I GOOFED.
They are Correct.

[chemelec]

Hi Folks,

Fixed the error - C7 is now a stacked poly. Here are the updated Eagle files.

@ Steve: Really I have come to the end of the road with the Surf PI project. I have a nice detector that works quite well and that I am satisfied with. I'm now moving on to fully digital, PIC controlled PI's. If you would like to take up the baton and make the improvements you have suggested then feel free to use my layout as a starting point.

Regards, Jim.

I Do Not believe this board or Schematic is correct.

With the Pin Connections to the 4066, Pins 10, 11 & 12 do not pass a signal out.

Removing these IC Pins from the Socket and Jumping pins 11 & 12 Together Does appear to work Ok.

[chemelec]

this may be useful to some of you just check its up todate, project i never got round to its using the large board like above if you need the copper side etc just ask.
All i want is a thankyou

Regards

I Do Not believe this board is correct.
With the Pin Connections to the 4066, Pins 10, 11 & 12 do not pass a signal out.

Removing these IC Pins from the Socket and Jumping pins 11 & 12 Together Does appear to work Ok.