P3A amp 100 watts Help

[israfel]

Guys im encountering problems with my amp, I already testing its output for DC,I only record about 10mV. But when I started playing it the 10 ohms resistor 1 watt started to get so hot, that was the resistor that connects to the ground

[jiggins20]

mainit rin ba output trannies?what is  ur quiescent current?

[israfel]

output trannies is in normal temperature,my quiescent current is set to minimum setting.

[israfel]

ginamit ko poh ang pcb na shared by jayke which is nasa thread pa too bad di pa ako maka post ng may image.

[a.out (drako65)]

ano voltage/current before the nag-iinit na resistor?

[israfel]

hmmm il try to check the output voltage and current

[jiggins20]

10 ohms ba talaga yun.nameasure mo ba?

[tony]

Guys im encountering problems with my amp, I already testing its output for DC,I only record about 10mV. But when I started playing it the 10 ohms resistor 1 watt started to get so hot, that was the resistor that connects to the ground

could be a sign of the output stage oscillating at radio frequencies, one measure would be to put a 10 ohm base stopping resistors close to the base of the output transistor.

were you playing loud when that happened?

the topology of the output stage is prone to oscilations.....

[Disabled]

ask ko lang mga master kung pwede 2 npn output transistors gamitin ko dito instead of complimentary.meron ako dito 2ps 2sc5200 tsaka 2pcs 2sd1047 sayang naman 

[tony]

ask ko lang mga master kung pwede 2 npn output transistors gamitin ko dito instead of complimentary.meron ako dito 2ps 2sc5200 tsaka 2pcs 2sd1047 sayang naman 

pwede, yung itaas na power tranie at driver magiging emitter followers instead na compound pair...

yung sa baba as is yon.....

[pEN DoTA]

ang galing n master tony pag audio ang pag uusapan....

[israfel]

@tony
Yes sir when i started to play it loud the resistor of 10ohms is starting to get burned

[israfel]

Btw sir tony how can i fix the trouble?any suggestions?
and before I forget is it okay if I used 0.1uf capacitor that connect to the ground and output to the speaker sa case ko kasi d2 there no available 100nf..

[israfel]

10 ohms ba talaga yun.nameasure mo ba?

yes it was the 10ohms resistor na prang shunt pra sa ground.

[jiggins20]

0.1 uf mylar cap ba ang nilagay mo sis?

[Disabled]

pwede, yung itaas na power tranie at driver magiging emitter followers instead na compound pair...

yung sa baba as is yon.....

ahhh, ok po sir tony maraming salamat po. +1

[tony]

Btw sir tony how can i fix the trouble?any suggestions?
and before I forget is it okay if I used 0.1uf capacitor that connect to the ground and output to the speaker sa case ko kasi d2 there no available 100nf..

0.1uf = 100nf
0.01uf= 10nf
0.001uf= 1nf

the 0.1ufd is in series with the 10ohm resistor, it is also called a "boucherot cell"...

[israfel]

0.1 uf mylar cap ba ang nilagay mo sis?

yes sis 0.1uf mylar replacement sa 100nf is it okay?

[israfel]

@tony
sir with the problem im encountering w/c the resistor of 10 ohms is getting burned when im starting to playing loud what should be done?

[tony]

did you connect that in series with the 0.1uf capacitor? you can try 5watt resistors...