Hi, don’t attached ur input ground with the psu ground that could be the caused of hum, those should be separated, i think input is ground lifted with the 10R resistor.then 45 0 45 ac should atleast have a 63 0 63 dc. I had the same problem when i started building diy amp but not the sr200 and soon I realised that the performance or the workability of the amp depends on the parts you used especially the transistors and ic, always get it from reputable source( farnel, mouser, etc...). The SR200 is a very stable and reliable amp. The first time i built this amp, i power it up then the only thing i did is adjusted the bias and everything works properly. And don’t expect to get 200watts from this amp if you are not using the recommended power supply. It is quite a challenge troubleshooting your build, but we have been on that situations just don’t give up atleast it works. Read about proper grounding your amp Rod Elliot has those articles. Hope for your success
Regards,
mj777
Hi, don’t attached ur input ground with the psu ground that could be the caused of hum, those should be separated, i think input is ground lifted with the 10R resistor.then 45 0 45 ac should atleast have a 63 0 63 dc. I had the same problem when i started building diy amp but not the sr200 and soon I realised that the performance or the workability of the amp depends on the parts you used especially the transistors and ic, always get it from reputable source( farnel, mouser, etc...). The SR200 is a very stable and reliable amp. The first time i built this amp, i power it up then the only thing i did is adjusted the bias and everything works properly. And don’t expect to get 200watts from this amp if you are not using the recommended power supply. It is quite a challenge troubleshooting your build, but we have been on that situations just don’t give up atleast it works. Read about proper grounding your amp Rod Elliot has those articles. Hope for your success
Regards,
mj777
voltage of your PSU is OK,you did not say what power of transformer is?
mobile phone might not be a good source of input signal for an amplifier due it's class-d output. try to use CD-player, connect it's output over 10 or 20kOhm potentiometer to an amplifier input.
also pay good attention to what it was said two posts above, how have you connected input gnd and PSU gnd.
mobile phone might not be a good source of input signal for an amplifier due it's class-d output. try to use CD-player, connect it's output over 10 or 20kOhm potentiometer to an amplifier input.
also pay good attention to what it was said two posts above, how have you connected input gnd and PSU gnd.
Here two problems in my work
1, Sir u right my psu capacitor bad some time they produce hum or little sound. Now I change them with 15000uf/80v best brands.
2, As I say in last post I m rookies, I use wrong resistances because value on resistance r blur. Likely A Diy member
(Who come in my city for business reason) he contact me and check the board then we noticed we use wrong resistance. I replaced all these resistance, now amplifier working superb. I feel very sorry with my little mistake we disturb u so many times. But with ur experience amplifier working fine.
3, one more thing we just play the amp with 100w series load in main supply, any suggestions before removing that load. Sorry for my mistake and Big thanks you and Mr Miles depth from my Heart.
Regards
Sunny
1, Sir u right my psu capacitor bad some time they produce hum or little sound. Now I change them with 15000uf/80v best brands.
2, As I say in last post I m rookies, I use wrong resistances because value on resistance r blur. Likely A Diy member
(Who come in my city for business reason) he contact me and check the board then we noticed we use wrong resistance. I replaced all these resistance, now amplifier working superb. I feel very sorry with my little mistake we disturb u so many times. But with ur experience amplifier working fine.
3, one more thing we just play the amp with 100w series load in main supply, any suggestions before removing that load. Sorry for my mistake and Big thanks you and Mr Miles depth from my Heart.
Regards
Sunny
Mr. Sunny next time always check values of each individual resistor even if you know the color code well it does not hurt to measure it before is place on the PCB and solder a 10 ohm and a 100 ohm in a quick glance look the same if you are into too much hurry do things like art take your time a master piece takes time 