luvdunhill said:
what's that? what's the output look like into a 100pF load?
"That" is me playing with a couple of transistors and chokes. I wanted to see how far I could go with voltage gain and still maintain a decent looking sine-wave...
As far as the 100pF goes, I'll load it into the sim and see.
I coupled a 100pF cap to each output and took them to ground. There is no effect on the sine-wave.
BTW, I discovered that the positive rail doesn't require more than 15 volts. It's the bottom (negative) rail that wants voltage. It's scalable--just don't input as much voltage and the output is happy. I just ran it with 30 volt negative rails and it looks great with two volts input.
BTW, I discovered that the positive rail doesn't require more than 15 volts. It's the bottom (negative) rail that wants voltage. It's scalable--just don't input as much voltage and the output is happy. I just ran it with 30 volt negative rails and it looks great with two volts input.
I just coupled the output nodes with a 100pF cap (the 100pF caps to ground were removed) and the specs appear to remain the same.
http://www.diyaudio.com/forums/attachment.php?s=&postid=1486025&stamp=1208376110
Within short time, i have one channel good for testing, but could some explain howto adjust the thing. ?
I suppose, as it look''s like the
that attennuation, should be at input ?, and that R6/R7, R18/R21 forms the gain of the circuit. ?
I also suppose that both +in and -in must be shorted to GND (or attennuator at zero - thanks ZenMod for those lessons btw.. back when we did
😀) ... , and that i have to make a ''jumper'' to connect pgnd and sgnd ?
Jesper.
Within short time, i have one channel good for testing, but could some explain howto adjust the thing. ?
I suppose, as it look''s like the

I also suppose that both +in and -in must be shorted to GND (or attennuator at zero - thanks ZenMod for those lessons btw.. back when we did

Jesper.
lykkedk said:http://www.diyaudio.com/forums/attachment.php?s=&postid=1486025&stamp=1208376110
Within short time, i have one channel good for testing, but could some explain howto adjust the thing. ?
I suppose, as it look''s like thethat attennuation, should be at input ?, and that R6/R7, R18/R21 forms the gain of the circuit. ?
I also suppose that both +in and -in must be shorted to GND (or attennuator at zero - thanks ZenMod for those lessons btw.. back when we did😀) ... , and that i have to make a ''jumper'' to connect pgnd and sgnd ?
Jesper.
before powering up :
set R25 to max value
set both R5 and R11 to mid point (value ) if they aren't already
then ( after powering up) - adjust R25 to have 15 mA through center CCS , or 3V3 across R24
then set R5 to have 1V to 1V5 across R1
then set R11 to have same voltage across R17 , or - BETTER - to have 0V between drains of Q1 and Q6
all inputs grounded
pot on input
let beast cook for some time , then recheck settings with R5 and R11
I presume/resume that procedure is simple and self-explanatory

lykkedk said:Yep.. just what i needed...
Very good cook-book for non novices 😀 ...
Jesper.
Well, before you power it up, I want you to know that I am happy to have known you 😀
Magura 🙂
Magura said:
Well, before you power it up, I want you to know that I am happy to have known you 😀
Magura 🙂
Me too, see you on the other side😉 Lykke was one heck of a guy😀
🙂
He is still alive, I just had him on the phone 😀
Drek still not powered up, but he is gaining courage to flick the switch 😎
Magura 🙂
Drek still not powered up, but he is gaining courage to flick the switch 😎
Magura 🙂
Magura said:I just had him on the phone
Maybe because he is still burning ?
The good think about Magura, is that sometime's i just can't see, the logic, and then he help's me out--- thanks Morten...
Jesper.
Jesper.
jacco vermeulen said:
Maybe because he is still burning ?
I doubt it, no squealing was detected 😀
Magura 🙂
Magura said:BTW, Jesper drop me your addy, and I'll send you a couple of those caps you lack.
Magura 🙂
better send him a Coppertone ........

Zen Mod said:
better send him a Coppertone ........![]()
So you think he's gonna wear a pale white tan, once he gets it up and running, due to outrageous number of hours in the shed?

Magura 🙂
Magura said:
So you think he's gonna wear a pale white tan, once he gets it up and running, due to outrageous number of hours in the shed?
Magura 🙂

so - what lykkkkk sez - when he's gonna power up squib ?
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