Please say me, can apex ax-14 work with 25-26v dc? I have 0,4v dc on output -((( Or should I find a higher voltage transformer Than 18v AC...
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it can work, so after rectification is 25V DC? the transformer is how many VA? is it bulky and large?
uhm... 160VA? 18 x 1.4142 = 25VDC + cap filtering might go close to 28VDC yeah I think might work so add 30,000uF to that I mean is that what you got on hand try that first 🙂
can someone throw a scheme with the signed voltages at various points? then I would try to understand why I have a constant voltage of 0.4 V at the output
sorry bro I'm in Puerto Rico maybe the local time for the more experience guys are sleeping xD try later 🙂 if you mean bias is too easy just measure voltage across any emitter resistor and adjust to 23.5mV to 26mV offset is low I measure one of mine and it was 15mV of offset that is pretty good for me that was a long time ago 😛
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ax14 probelm in high frequency
hi apex sir i made this amp ax14 from 253 layout it works but in high frequency it is not good .i do everything what i can.i use first 100pf then change to 22 pf and 33 pf in place of 47 pf but nothing works.amplifier is not good in hf driver .sshh sound coming along some place where is high frequency instrument.please help i made so much pcb already.amp is running with 2 pair and 40 +- dc rail voltage . i change biasing no different.please help.
hi apex sir i made this amp ax14 from 253 layout it works but in high frequency it is not good .i do everything what i can.i use first 100pf then change to 22 pf and 33 pf in place of 47 pf but nothing works.amplifier is not good in hf driver .sshh sound coming along some place where is high frequency instrument.please help i made so much pcb already.amp is running with 2 pair and 40 +- dc rail voltage . i change biasing no different.please help.
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Rohin,
What are you using as a power supply?
Are you hearing the noise or seeing it on an oscilloscope?
What are you using as a power supply?
Are you hearing the noise or seeing it on an oscilloscope?
try place a 4.7ohms resistor from power supply GND to audio input negative to see if that might resolve the problem
Sir Juan solved the problem.he is really good person
What was your problem he killed?
Thought Rohin was having a problem with HF?
<<Anyone else confused?>>
Thought Rohin was having a problem with HF?
<<Anyone else confused?>>
Thanks to everyone i used transformer 30 0 30 with good caps. Yes i put already 10r resistance to input negative. My hf is good on other amplifier. Problem in circuit i think no one test ax14 on hf driver .layout and other things goods sound is coming with good pressure when raised 15 k hz fader it make distortion.