I was intrigued by the active servo psu design in post #9450 for which prasi has done an excellent pcb layout. Its not immediately obvious to me exactly how it works, but looks to be a noise cancelling design where the opamp has unity dc gain and an ac gain of 30 - why 30? I'd be very grateful if you could enlighten me apexaudio. I see pcbs and kits using this design on ebay so I guess you're aware that your(?) design is widely copied in China.
Andrew thats simply not fair comment. Most are tested and most (almost all😀) are working.
dont you agree that they (posted designs) are different topology and gives one a chance to study and compare ? and most importantly, when tested by enthusiasts which is exciting for prolific builders like olafK, Terry, 44250, and many others? Find out the flaws, if any, with design and find the solution?
e.g. Just one example that I had the experience, there are many more in the thread with different people. its the FX-8 amp that has given good experience, the feedback ckt values were changed after Terry posted scope shots, which gave almost perfect square wave response on scope for bass frequencies.
Most would agree its all DIYA is about, people will feel they have contributed.
If one posted all tested designs, then it will become boring for some adventure seeking enthusiasts very quickly and it may even lead to finding some other past time.
My opinions/guesstimates only, based on reading of this thread!
Thank you very much Prasi. I apreciate your gesture! Post here when you finish the pcb. Thank you again! All the best.
I like the thread as it is. Terry once said it's like a candy store and that's exactly how it is.
regards Olaf
Can you or someone point me to the datasheet of switch? I need to prepare a package.
Prasi i don`t know what switch use this circuit. Put only the conection pad, i will connect the swich with wire. Or choose a simple switch.
Hi Mile! What need to change for 2x48V AC? Thanks!
An externally hosted image should be here but it was not working when we last tested it.
Hello I love the sound,
Here is a rough layout, I am not sure about switch. So just given 6 pads.
Reg
Prasi
Attachments
Thank you Dacz, that's very helpful.
I will use it to make revised layout, where switch is on front panel adjacent to pot.
Reg
Prasi
Here is the revised layout with switch. Sch and switch datasheet also attached.
Thank you dacz for suggestions.
Thank you dacz for suggestions.
Attachments
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