Need help with ebay PHONO TURNTABLE PREAMP PREAMPLIFIER PCB DIY KIT

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About a month ago I was browsing and noticed this phono preamp pcb $15.00 shipped. I got the pcb in the mail and it came with a paper with a URL to get to a page with a parts list and a pic of the pcb with some notes:confused:. I went and ordered the parts from mouser and got them today.

Just wanted to know if anybody else here attempted to build one of these? I am starting to think that it was too dumb of me to purchase this item, let along order the parts:xeye:. I am a noobie when it comes to DIY stuff.

If anybody else have any experience putting this particular phone preamp, a pic of the finished item would be greatly appreciated.

Thank you in advance,
Chris
 
About a month ago I was browsing and noticed this phono preamp pcb $15.00 shipped. I got the pcb in the mail and it came with a paper with a URL to get to a page with a parts list and a pic of the pcb with some notes:confused:. I went and ordered the parts from mouser and got them today.

Just wanted to know if anybody else here attempted to build one of these? I am starting to think that it was too dumb of me to purchase this item, let along order the parts:xeye:. I am a noobie when it comes to DIY stuff.

If anybody else have any experience putting this particular phone preamp, a pic of the finished item would be greatly appreciated.

Thank you in advance,
Chris

Hi Chris
Sorry to say but the board as pictured has some bad errors

The board is 3x dual op amp based. Most op amp circuits run with dual polarity voltage supplies. In the case of this board it has an error with its marked polarity of power supply cap. Pin 8 is V+ pin 4 is V- note the marking of cap is the same for each polarity.:eek: You could allow for this during construction. But if it is a single sided board, there appears to be NO connection for voltage to get to V- :eek: There is no input capacitor provided. :eek: otherwise The board follows a layout of 3 non inverting stages.

With a lot of experience and patience it may be possible to work around these board errors, but its not a good start inclining toward DO NOT start, can you scan and provide the schematic.

Cheers / Chris :)
 
Hi Chris
Sorry to say but the board as pictured has some bad errors

The board is 3x dual op amp based. Most op amp circuits run with dual polarity voltage supplies. In the case of this board it has an error with its marked polarity of power supply cap. Pin 8 is V+ pin 4 is V- note the marking of cap is the same for each polarity.:eek: You could allow for this during construction. But if it is a single sided board, there appears to be NO connection for voltage to get to V- :eek: There is no input capacitor provided. :eek: otherwise The board follows a layout of 3 non inverting stages.

With a lot of experience and patience it may be possible to work around these board errors, but its not a good start inclining toward DO NOT start, can you scan and provide the schematic.

Cheers / Chris :)

Chris,

Thank you for checking it out. The seller did not provide a schematic. He provided a URL to download this document.

Regards,
Chris
 

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I am starting to think that it was too dumb of me to purchase this item, let along order the parts:xeye:. I am a noobie when it comes to DIY stuff.
Now you've got the stuff, you may as well build it. :)

I'd suggest using sockets for the chips. If you solder the chips directly to the PCB, there's a risk of heat damage (especially if your soldering skills aren't great), and they're almost impossible to get out again.

Good luck!
 
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