Pavel Dudek's super Gainclone group buy

[noviygera]

Congrats! Go for it. I am wondering why no one can make a subjective evaluation of the sound from this amp.

 

[clog]

Subjective evaluation of PA03

@noviygera You may want to check out this post:

http://www.diyaudio.com/forums/chip-amps/277812-yet-another-lm4780-amp.html#post4429271

 

[peranders]

The interest is increasing, that's good.

 

[clog]

transformer wiring to PA03

Peranders, I am very indecisive how to wire my transformer to your board.
Is the chosen way in the picture correct ??

 

[JammyBStard]

Hi Clog
Its shown on the scematic downloaded here:
http://sjostrom.pro/wiki/tiki-index.php?page=PA03+third+round+Group+Buy
Don't forget to check your primary wiring is correct for your mains voltage too (110/230)

Sent from my SM-G920F using Tapatalk

 

[clog]

Of course I have seen the schematic but then I stumbled upon this post
http://www.diyaudio.com/forums/chip-amps/277081-pa03-startup-mistake.html

 

[peranders]

Hi Clog
Its shown on the scematic downloaded here:
Group Buy arranged by Per-Anders Sjostrom | PA03 third round Group Buy
Don't forget to check your primary wiring is correct for your mains voltage too (110/230)

Sent from my SM-G920F using Tapatalk

Remember one winding with dot to ground and the other winding "no dot" to ground, exactly according to the schematic.

 

[JammyBStard]

I think what's happened with redjr is he/she has been using a transformer with single secondry with a centre tap. Rather than a transformer with two secondry windings. so when redjr connected the single secondy accross the outer pins it would have shorted the transformer. If your transformer has two secondry windings as per your diagram just do as the schematic shows.


Sent from my SM-G920F using Tapatalk

 

[clog]

Thanks peranders and JammyBStard. When I saw the schematic and my transformer I thought wiring is easy. Then I saw the post by redjr and I thought "this is gonna be complicated". As I understand now just newbee worries.

 

[corneliup]

Hi,

I'm in for 2 boards.

Thanks,
Corneliup

 

[peranders]

Nice. I'll hope we can reach the 50 pcs. limit.

 

[reaper996]

Peranders:

Put me down for two boards.

 

[peranders]

Please sign up at my wiki page.

 

[reaper996]

Not sure how to add myself to your group buy page.

 

[peranders]

Register yourself and just edit the page.

 

[peranders]

Do you think we can reach 50 boards?

 

[kallel123]

one part left to finish one of my boards the inductors lol.do you have any left?if so, can i get Eight? will need as many to finish all my boards which will be four altogether four daughters four boards lol.ill post pictures soon...😎

 

[peranders]

Last time I had those inductors made by a company but this time you have to wind them yourself, not that hard. It's just 15 turns with 1.3 mm copper wire.

 

[peranders]

I need 21 more boards...

 

[gabe75]

lm4780 board

how much is one board going to be?thanks