Aleph J-X Amp Project

[Bill Fuss]

I don't have his schematic in my files. Plus or minus.

 

[dhole]

its +22v

http://www.diyaudio.com/forums/pass-labs/145387-aleph-j-x-amp-project-53.html#post2005744

 

[Bill Fuss]

Whats the voltage to the output gates?

 

[dhole]

-23

 

[Bill Fuss]

26.8 - 23 = +3.8 Thats in the ballpark. It's then in the output section. Check your drop across your source resistors and see if the signal fet is shut off or the CS is wide open.

 

[Bill Fuss]

Are you still there?

 

[dhole]

the drop accross the source resistor is 11v

 

[Bill Fuss]

We need the output schematic cause that ain't right. 11v / .47 ohms is 22 amps.

 

[dhole]

the rest of the circuit is as the aleph j original. i measured the wrong resistor...

 

[dhole]

its 7.3v

 

[Rodeodave]

As always, please post a schematic and a picture of the actual setup. You wouldn't believe what some people can spot in a picture...

 

[Bill Fuss]

its 7.3v

You should have around .6v across R16 and R18. Which one is off?

 

[dhole]

getting confused bill with current source resistor and source resistors. No voltage accross the resistors .

 

[dhole]

or 0.03v ?!

 

[Bill Fuss]

R16 is the source R for the current source fet, R18 is the source R for the signal fet. Hook your probes to both ends of each one and measure again.

 

[dhole]

R16 is the source R for the current source fet, R18 is the source R for the signal fet. Hook your probes to both ends of each one and measure again.

Bill

R16 is 0.06v and R18 is 0.01v

 

[dhole]

and the other side r16 0.05 and r18 0.00

 

[Rodeodave]

What's the voltage across the Zener? Is it oriented correctly?

 

[dhole]

Im not using any zeners.

 

[Bill Fuss]

It would make sense if they were .6 and .1, but if those are the real readings you have seriously miswired the PS to the output section. That would be only 100ma of offset, Rg would not be smoking. Time for some pics.