my first step to class A amp -aleph3 3ow.

[space2000]

Hi all,

Today I just tried to make Aleph3 30w class A. once I build the circuit, it is working at the first step trial without any error. But some things I don’t really understand about “R8” and “R115”. Though I used pot but I need to clear this. Pls any one can help me?

Now my amp heat is about to 44c. its looks nice temp.

Need suggestion pls.

Thanks for help.

[Zen Mod]

Originally posted by space2000
Hi all,

Today I just tried to make Aleph3 30w class A. once I build the circuit, it is working at the first step trial without any error. But some things I don’t really understand about “R8” and “R115”. Though I used pot but I need to clear this. Pls any one can help me?

Now my amp heat is about to 44c. its looks nice temp.

Need suggestion pls.

Thanks for help.

exact schematic please ;

accidentally - I erased all resistor numbers in mine schematics of A30 ......



maybe attached file will help you - look at notes ( by courtesy of Algar_emi )

[space2000]

hi,

thanks you posted pdf file. yes this is the one i am building. mind led don't have any light, why is that for?

anyway can i put pot on R8 and R115, which value should be just nice for this circuit?

thank you.

[Zen Mod]

Originally posted by space2000
hi,

thanks you posted pdf file. yes this is the one i am building. mind led don't have any light, why is that for?

anyway can i put pot on R8 and R115, which value should be just nice for this circuit?

thank you.

led - you probably reversed it ( most often mistake )

R8 -- you can try without it , for start ; report what DC offsets on outputs are , so we'll know do you need them ;

R115 - leave it as is for start (820E ) , and later - when you learn few things , you can measure AC gain of output CCS ( upper output mosfets ) , and you'll know what to do .

[space2000]

thanks for help....now i am listing . led i tried to reversed but still no light.....

[Zen Mod]

replace the led .......

[space2000]

just check Dc output voltage is 0.226....what is the value should be there?

[space2000]

i want to know. as i have seen on aleph3 has used three pair of IRFP240. here per pair is 12.5 watts output so total is 36+ watts....can i add more output mosfets following the output rail?
i know there must be increase more power supply amp.

thank you.
mciahel

[ttan98]

You have so many amps where do you put them?

[space2000]

Originally posted by ttan98
You have so many amps where do you put them?

Good question.

actually i am learning by making many types of amp as i can. it is my hobby. i just make my own and keep as well. my friend took two to listen. one i make for my uncle he is very happy. i never took any extra money for workmenship or anythings at all. they will return me when they can....only to my uncle, i gave him as a present.

thanks for asking...