No NFB line amp (GainWire mk2)

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I hate hand soldering SMD. It's way too time consuming to align all the pieces individually. I'd prefer through hole for that.

I've done home etched boards for years in a toaster oven. Parts would align themselves while in the oven. Since I've gotten lazy and get my boards etched in China, I've ran into problems with components moving completely out of place and my boards are browning. I've got a better temperature controller 3/4 built to run the oven. I may need to use paste stencils for solder too.
 
I hate hand soldering SMD. It's way too time consuming to align all the pieces individually. I'd prefer through hole for that.

I've done home etched boards for years in a toaster oven. Parts would align themselves while in the oven. Since I've gotten lazy and get my boards etched in China, I've ran into problems with components moving completely out of place and my boards are browning. I've got a better temperature controller 3/4 built to run the oven. I may need to use paste stencils for solder too.
Years ago i bought a microcontroller, from elektor ,for use in A reflow oven but never finished this project.
 
J1,J2,J3 schematics & pcb(FOOTPRINT) don't match. What is the right one?
Please look at the picture J1=2sk117 ,J3,J2=BF245A.
 

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J1,J2,J3 schematics & pcb(FOOTPRINT) don't match. What is the right one?
Please look at the picture J1=2sk117 ,J3,J2=BF245A.

J2 and J3 originally are 2N5457 and the footprint is OK for them, if you want to use BF245A you should rotate for 180 degree.
You know that a drain and a source are interchangeable for JFETs. You can rotate 2SK170 or leave it as it is, it will still work. It was to late to change silk screen when I ordered the board.
 
J2 and J3 originally are 2N5457 and the footprint is OK for them, if you want to use BF245A you should rotate for 180 degree.
You know that a drain and a source are interchangeable for JFETs. You can rotate 2SK170 or leave it as it is, it will still work. It was to late to change silk screen when I ordered the board.
Ok ,so i can power this using the original power supply this afternoon .
I want say thanks to Jeff, who sent me 4 pieces DN2540 for free.
I want say thanks to Vallery, who sent me 4 pieces 2sk117 for free also.
A great thanks to Damir of course ,who offer the schematic .
Best Regards.
Thimios.
 
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mk2 lower gain

A GainWire lower gain version(CFA mode) ,using RightMark software.
Please keep in mind ,this is what MY sound card measure.Probably the GainWire is much better!
 

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A GainWire lower gain version(CFA mode) ,using RightMark software.
Please keep in mind ,this is what MY sound card measure.Probably the GainWire is much better!

I wanted to ask you what's that 50Hz hump on the distortion graphs, and than I see different text "Please keep in mind ,this is what MY sound card measure.Probably the GainWire is much better" ?
How is that possible?

edit: after I quoted you I can see complete text?????
 
I wanted to ask you what's that 50Hz hump on the distortion graphs, and than I see different text "Please keep in mind ,this is what MY sound card measure.Probably the GainWire is much better" ?
How is that possible?
This 50Hz hum is something i see always when testing with my p.c. I don't know why:(
My sound card is an esi julia (pci).
I'm sure with a better sound card the GainWire will measure even better.(lower distortion)
 
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