Simple Symetrical Amplifier

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That won't help at all. :)

Still, the bias could not be set (in the simulator), and after changing these resistors it could. For as far as I can see, these resistors are parallel to the bias regulator, if the voltage does not rise to the required level (over the bias regulator) I figured that raising the value of these resistors might help (and it did, in the simulator). Probably due to the 10ohm emitter resistors? If I am wrong then please explain why, so I can understand your design better.

Regards,
Frans.
 
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Here is the voltages on the input transistors, but I am no shure are they in written order
 

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Here is the voltages on the input transistors, but I am no shure are they in written order

As I said, you don't have +/-15 V on zeners referenced to GND. On cathode ZD1 there should be +15V, on anode ZD2 there should be -15V referenced to GND potential. There is your must starting point if these two aren't correct, forget all the other voltage readings. :cool:
 
It is not 15V rather measured 14,7V?

Look Josip, zener diode is not a voltage reference, its voltage potential is also zener current/production dependent, so across zener diode you should measure something from 14,5V to 15,5V (15V+/-0,5V). ;)

But until you won't have both zener diode potentials correct, it is no use to measure other points potentials as well. :rolleyes:

P.S. This is completely basic electronic knowledge, so I am afraid that you will have to look to some books or wikipedia too. ;)
 
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ive seen a few designs on here and i like the look of the one with exicon lateral fets as i have some already, just two questions;

has anyone built and tested it, because i need -3db over 500khz top end and wanted to check?

and, ive seen what looks like and eagle board but as jpeg, does any one have the eagle file i can use as a starting point, i know its cheeky but i have small kids and i dont get much time.

thanks, steve.
 
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