Hi Jun,
I sent you PM, Thanks... Mr. Mile apologize in advance for this off topic.
Regards,
A little but very important detail/information from you Sir, is very much appreciated. Once again, thank you very much APEX.
sir I made this amp but its cross current do not increase and decrease by 1k preset,plz help
Dear Mr. Mile S...
I have a problem now on my second built SR200 amp, I can not set bias for one channel, the other one is just fine. Both of them sound good also, but they have difference heat sink temperature (because of bias setting I guess), and the one that I can set bias is sound better that the other one.
I already changed DB139, 2sc4793/2sa1837. I have check all small transistor (bc's) I think they are OK...
I need you advice.
Thank you so much..
Best Regards..
I have a problem now on my second built SR200 amp, I can not set bias for one channel, the other one is just fine. Both of them sound good also, but they have difference heat sink temperature (because of bias setting I guess), and the one that I can set bias is sound better that the other one.
I already changed DB139, 2sc4793/2sa1837. I have check all small transistor (bc's) I think they are OK...
I need you advice.
Thank you so much..
Best Regards..
Ok I will measure R28, R29 and R30...and report the result..
Many Thanks
Best Regards
I have just got back for couple days out of town. Resistor Voltage Measurements conducted last night. Here there are, Supply was 40VAC/55VDC:
R28 = 0,150V , R29 = 0,91V , R30 = 0,42V
Thank you so much
Best Regards...
R28 = 0,150V , R29 = 0,91V , R30 = 0,42V
Thank you so much
Best Regards...
R29 = 0,91V or 0,091V ?? What is voltage on P1 ( can be 0V - 0,4V)?
Vbe (BD139) = V(R29) + V(P1) = 0,55V.
Dear Mr. Mile S.,
R11=6,96V and R27=0,15V...
What is P1, I am sorry for asking...
I will measure R29 once again to ensure it's voltage.. also check Vbe voltage...
Thank you so much...
R11=6,96V and R27=0,15V...
What is P1, I am sorry for asking...
I will measure R29 once again to ensure it's voltage.. also check Vbe voltage...
Thank you so much...
Ok, I will buy resistors to replace R9 and R10...
Thank you so much
Best Regards...
Arif
Last night I used jumper instead of R10 (to make R9 and R10 = 2K2 both), measured zener diode 15v (D2) = 7,4 volt .
Measurement also conducted on zener diode 15v (D1) = 7,5 volt with R7 and R8 are still 2K2 each...Do D1 and D2 need to be replaced?
I measured the other SR200 channel, both of D1 and D2 are 15 volt..and I can set bias without problem...
I need your advice...
Thank you so much
Best Regards..
Mr. Mile S...
Absolutely right...
Last night I replaced those two zener diodes, install back 2k2 resistor and check the diodes...Finally I got 15Volt on those ones...Thank you so much..
For the first run I set 1V on R10 (instead of fuse)...
Dc offset measured at 24mv...it is a little bit high, isn't it?...But I have not test the sound yet, it was too late of night....
I will try to take pictures and post them in this forum...
Thank you so much Mr. Mile S. for sharing this SR200 design...
Best Regards...
Arif