Surf PI Pro

[Carl-NC]

Since everyone and their dog has traced out the SMPI-pro, I may as well post the official schematic. No secrets anyway, this is about as vanilla PI as you can get.

- Carl

[homefire]

Bummer! All I see is the blank scheen.

[bernte_one]

nice!

love the way you fit in the pots, no more irritation about the right direction.

who can make a small pcb lay file? (black white)

regards bernd

[ApBerg]

Wow ! Thanks !

Clear schematic from a very good nice working PI detector !

Think we all Love Carl !!

[Alexismex]

Hello Carl,
Thank for this good schematic, can you tell me what is the real purpose of C1???

[homefire]

My Guess is to take the Scratch noise out of the Pot Moving! LOL

[Carl-NC]

Hello Carl,
Thank for this good schematic, can you tell me what is the real purpose of C1???

Don't know, unless it is primarily for the clicker version. Or, it may take a little harshness out of the audio.

[kt315]

Hello Carl,
Thank for this good schematic, can you tell me what is the real purpose of C1???

it has relation to piezodielectric phone use imo... may be it is so specific... you need to decrease resonanse effect of it?

[Alexismex]

Thank you very much i have to test in vitro to see the result.......

[Dr Vel]

100 pf is not going to relate to any resonance at audio frequencies with the piezo phones. My guess would be to reduce a pink noise hiss in the phones. One question I have is does anyone see a reason dynamic phones could not be used if a capacitor of say 0.22 uF poly was put in series at point 1 to block the DC current flow.

[TH Jim]

Thanks Carl for the schematic,

I have already changed my SMPI to be more like the Pro and like the results!

Very useful!

Cheers, Jim.

[golfnut]

Hi I can see its a png file but my ol XP is struggling with this.

Anyone re-post it as a jpeg pls

Steve

[maikl]

Here are the PNG but no problem (lower resolution)...

[ApBerg]

JPG

Hi I can see its a png file but my ol XP is struggling with this.

Anyone re-post it as a jpeg pls

Steve

Hope this is ok

Best regards

[BillNEWAST]

Use IrfanView and make sure that All the Plugins are applied.
This is a Free Must Have Image Viewer and Editor.

Sincerely
Bill Adams