hi friends any idea why not working and getting dc at output?
Edit: İ take out cables for get clean pictures.
Edit: İ take out cables for get clean pictures.
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I would not use more than +35/0/-35 for an amp with single pair of output devices.
Search advices given by AndrewT (may his soul rest in peace). .
Divide both power transistor's power handling capacity by 4 atleast or 6 preferably for BJT for RMS power into 4 ohms load. . ..
Info isscattered on DIYA, but one needs to take into consideration the above factor of safety and also how to calculate RMS power for his speaker impedance.
Search advices given by AndrewT (may his soul rest in peace). .
Divide both power transistor's power handling capacity by 4 atleast or 6 preferably for BJT for RMS power into 4 ohms load. . ..
Info isscattered on DIYA, but one needs to take into consideration the above factor of safety and also how to calculate RMS power for his speaker impedance.
Initially check pcb print wire connection if all are correct then check mje350 and mje340 base and emitter because some transistor base emitter changed to each other
ty Prasi, i can rewind transformer its not problem for me. i did like that cause of kandimba said i should use 2x33vac.
RIP AndrewT. he was not just pointing what is wrong, he always explane why its wrong. he was trying to teach so his writes really important for us i always reading his writes and trying to understand with my little english.
just abouth this one there is more then 1000 pages and no one can read all these pages.
ty again for remembering AndrewT.
hi ty for answer me,
i check lines on pcb all is ok.
i check mje350 and mje340 they are ok and legs are ECB.
i take out and check Q1, Q2, Q3 2n5401 and Q7 bc547 they are ok
i juat didnt check Q3 Q4 and Q6
i will check resistor values again to day maybe i make mistakes abouth it but i dont think it can make this problem.
Dear sir
Please suggest me that in ax11 ampl .there is used mpsa13 but there is not availabe what is substitute of mpsa13
Please suggest me that in ax11 ampl .there is used mpsa13 but there is not availabe what is substitute of mpsa13
dont ask i dont know how to make that kind mistake.
i make the change now many things normal just no audio coming out 🙂)
sgnd connected on pgnd.
really strong humm coming out but no audio signal..
tomorrow i will check again if any one have idia pls write
edit: psu that i test not on board i take ac turn to dc and give to capasitors 2x8500uf and get 2x45v. maybe that hum coming out from that? in cae i will use psu protec from apexaudio cause of chase really small and it will feed 2 ax16. this is what is my plan.
thank you...
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My favourite npn transistor MPSA42, its mate the MPSA92 is good pnp.
It s a high voltage transistor so good for amplifier front ends.
CCS, CM, LTP etc etc
Yes but resistors around MPSA42 must be change, use 2k2 from base to colector and 1k from base to emiter.
hi mr mile,
yes i was thinking maybe its bad so i replace it with 2n5551. i will change after get bc547. thank you for checking.
there is another question i was going to write you. psu with protect have dc protect too? if its like that i will change plan and make psu+protect and 2 pair ax14. this cause of my chase small.
thank you..
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