F6 Amplifier

Member
Joined 2009
Paid Member
There is no value after the pot...
I guess its K3.
But I´ve been turning those trimpots from end to end without seing any change on the spectrum..

There Must be a value After the Pot!

Of course you should not turn down your software tone generator, otherwise you do not get your 2.83V as you told....
The 100kPot should bring down it a tenth at leas!

Make a simple voltage divider with two resistors, that shows at its input 2.83 and at he output the 1/10 value...
 
Either your source is too weak or something is strange with the amp. If I'm not mistaken you should be able to get about 14 V into 8 ohm and more into 4.

I can get 7 volts out from the amp driven from my laptop,so I don´t think it´s to weak,even thow it can´t drive it to full outpput.

There Must be a value After the Pot!

Of course you should not turn down your software tone generator, otherwise you do not get your 2.83V as you told....
The 100kPot should bring down it a tenth at leas!

Make a simple voltage divider with two resistors, that shows at its input 2.83 and at he output the 1/10 value...

I will make a divider,tomorrow..as I will do some soldering and it´s getting late here in Sweden. :)
Thank you all so far..
 
I can get 7 volts out from the amp driven from my laptop,so I don´t think it´s to weak,even thow it can´t drive it to full outpput.



I will make a divider,tomorrow..as I will do some soldering and it´s getting late here in Sweden. :)
Thank you all so far..

Ah.

Just to rule out possible culprits: have you tested to hook up the source output and see if it is well behaved with no visible distortion in the range you want to use it? For all we know it might distort massively above some level =)
 
God morgon..

This is how it looks with a 10k resistor in serie after the pot (pot fully turned)
and a 1k resistor to ground after the 10k.

Last_zps1ec9b5fa.jpg



As it should be?But still nothing happens as I turn the pots..
was thinkin if C1 and C2 where the wrong way around but they are not.
Strange as it is the same on both channels
 
I have succesfully used this setup.
http://www.diyaudio.com/forums/pass...e-power-amplifier-distortion-measurement.html
Testing is a pain, in that the setup can be tedious, but must be right to be helpful. Try looping your soundcard and see if you can alter levels and see changes that way. i know with one of the sound cards I used in the past, setup was a bear, having to make sure the program was receving the signal and that all volumes were adjusted and there was proper hardware control by the software.