Surf PI Pro

[TH Jim]

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.

[bernte_one]

many thanks Jim

regards bernd

[Mrand]

Attention! The capacitor C19 - 100pF (on the original schematic) is very important. He shortens the answer for several us.
Mrand

[mikebg]

Attention! The capacitor C19 - 100pF (on the original schematic) is very important. He shortens the answer for several us.
Mrand

It shortens and my brain.
Can somebody explain how to calculate capacitance of C19 ?

[Tepco]

You don't need to calculate. C19 is most probably added to reduce RF interference picked up by coil and cable. 100pF+2x1K provide rolloff slightly above any frequency important for PI target response. When high enough level RF enters opamp input, it is no longer amplified, input stage starts to rectify it instead, changing DC offset in response to RF envelope, spoiling detector operation (few such cases are reported on this forum whit different detectors).

[Mrand]

Before you will knock together the next joke, "extend your brain" and do some reading about the compensation the OP. Lead-Lag, Forward compensation, Compensation across modification of input impedance and other.
Mrand

[satdaveuk]

Hi Dave,

I'll send you a copy by email over the weekend.

Regards, Jim.

Thanks Jim your a gent

Regards

[mikebg]

Before you will knock together the next joke, "extend your brain" and do some reading about the compensation the OP. Lead-Lag, Forward compensation, Compensation across modification of input impedance and other.
Mrand

Thanks Mrand, but I think the circuit designer added the capacitor C19 experimentally (without mentioned by you knowledge).
See Ron Mancini pages 116 - 121.

[woodbob123]

question i asked had allready been covered

[bernte_one]

hello

i´m not able to extract a simple black white image from copper tracks and pads of pcb
from eagle layout viewer

can anyone post b/w image here?

thanks

[Mrand]

This is simply. You must mark suitable layers. 1-Top, 17-Pads, 18-Vias and 20-Dimension.
Afterwards to execute the sequence.
Menu: File\
Export
Image
Monochrome
PNG or Bitmapa
Enter
And picture is ready. I don't warrant the correctness of the scale.
Mrand

[WM6]

It would be nice from different PCB-design tools owners, always post PCB slide in Black/White presentation too.

Thanks in advance.

[samii]

Hello
open *.brd file,On view menü;displey hide layers, select pads via etc.
from file menu ,Print,select pdf format.

http://hotfile.com/dl/147652684/481a...PIPro.pdf.html

waiting for test show video

Best wishes
Sami

[samii]

black white pdf pcb

[WM6]

black white pdf pcb

Thank you samii!
Nice work.