Studio Reference Amplifier

Thank you for your concern! I know the rule but this is not the first amp that I test it this way,if you move fast and watch the bulb,nothing will happen! In fact,I did managed to blow a trace on one of the PCB's...the heatsink one...my test resistor fell and touched the LED trace! Changed the LED and the thing is back in action! I also found the culprit that didn't let me adjust the bias.Turns out that both of my multiturn resistors,were changing value only in one direction! Now I can set the bias.For now it's at 20mV across 0,33 ohms resistors.I will go higher but now I must solve the hum problem when no signal is fed in! Any idea on how to get rid of it?Or why it's present only when no signal is fed in? With signal,the amp is dead silent,also If I short the input the amp goes dead silent!


Please upload u full amp photo.and grd wire connection
 
Here are my final photos of SR200 Amplifier.
Qf2z9OKes13AfJfKHowlefAjYvLIaZGukcSHYbYfQyPOyRsWiaQwXiZ5tXwn7egpoNVQhrFUJ8DUBRimUi7nwBlohnfUgS4_lyK4qOlNxavwjs4aOn3h6wxavwhNZbkJdmdhyXUWuTXk0rkh8eddALHFN8PiXga5xoh1-ncvyUAP7Hswo-R_aRLyxSh66VwgpzfnFMGrb6x13TEAj5dZQuEQxH8AkVg0U5UeE8kfG_nxVDMwA6tYW471WpZFcccyOkWbQ1Bt2WfFrolj1s6wRLbtS34tvHl_owcDgOyeECc2PQN_EBpZLtWBi8w6Jfkl7tb4MX-WihTQv614mlJnKso8ydzaOvQgz4hKvZwdo7HF1q9R76wcDOqBjnIsh5DxE0AAg6AVg_56ZaV4oP0xQZD1qOI1OFW15gdGAgJOKZcetjrWB0muW6YVDkcloKdVDP2r3GoH3w2lb2wB4A8D25_8eEoQoryg67RUxIekGtiAB1HTam45itsPqxaEmQ8W35X36UMqGI7eKup4iu7ZSZhuyif4f4sW72yj_LHXJkkLwkTcyOmxkViw6cnWuhDRF_SYOmfaIcm3SzmGWuAFqNvobYZ99sgYNQwX-AUmAHxYksL5aEQ9JUhCB63LKWXDupeDTwZx9GOitmcC9yF-w4JZI0kpJ0HNy0x33WdjziMKW7lD_t4evOzKLGdw=w999-h749-no

V_SPO_46P0qnLS5R_McQDs8HHYZW2xxC8R0LUqHweVhN97lYr-aLWSn69KMTaQKyDHVodmqjEIAyp92qfB3AGrGeS2tcSClyxqCdae6mqJZVlbFamseKkrcOcwzSKz-aoKAeKCtEQRM-yTxNovfKvLcsHHuOZk3dh1Nosd5XpABFmbUFewdBvO__kd5vBiPmYIaQazIJ6IOGq-ZFFQotvuuUrB2XEWZzQqEmOpWcLtJdmYNK8K3Dzu9TN0dRaajyQRNXzU-r2AkAhO5smZX0WvSfCVBp7OSm8ZIdwYohIbGBqwIK6cAtoUbQ72Q1GaCh_0mv1CApHrtiel9pl32id7-pIi2ehWdmw_kh-p8SPILTTLV9V0bi-GPDI5gzXUEmX8ANrygQu-fRe4i-xkFfRolyLYELLupGsylFQRfycnJyhpSExnyMOUUQQHr52gkuznt7POtt62ngeWkip5FD_UiGfEb9Xg3fr7vpYLkL-uyGQELFy0UHkdjKOTUbnxBalQdMeXll_6wqmAbNJReNZ_XdM8ysjugpyjEBGehatVUKhk_c5t7ASUd37TT5Nrat6LcGUrNrZw7ZC7we2QS6vj8LxC5PWYKxAWfU8s6ZY1loiZeBYKWpyxV0HO6q7KMoEaZndmXbgnLVBCEmMFAxtG4DTonk_EJF2IbcjIJ1Wz6OvSyaIEqGPw_g_DsE=w999-h749-no

IXfuDHRC8YbVunSg-0ZCXp0T2uLC_x6aoESWP2f0uUA5sDNbRpw5Z8Gl2UFTZ-VsUbPKGN05UPfYSZvhu9WvCItlRudb5U7r7Z92ZfxK3HL35lf_R3vz526bGEO_MAmZiC_SCRMohvRJ3Qg3a67ba7GQO-vsYx-qu4M49ANDxv3HN4M8dGu5Jw0NtgS8I-hf7TjFKpfxJ--sm5LaRQ0ueYfU-YEWgsZpydiIk_r5mwkorxuvM3fXrHlR6bACghkQQ6XE5GGiwBHjh3vNOOBiT9tveDy6RiPdb0qaq51BZU5l4ilo4G8cX4zOPzUIXkakMDxkhtM8yL8ihFhk2Xfcb62jFOKkgaLD3IF-P50w-x0xjsaaAI9BwwLAktL8GfK-fHlw-ovS7-r8aSaregm7w8wZ6IzpuN2vbcXObulGF6JNZNsEq-VMjwJC-P1ckLhTt0nc9DrJbTdT4utBymui5jtEeqCXLVrtyigtR2Xi2PmVz7DElHzHFVix52QzBGgjiyCgx8oQXxb5KeSqHXXy7zlB837x9SMMDbZaitRftz7sdhhGDGIadKNCbtC_ZddbLVY6bFxLbagF699OTPtWvFbqZMLotun7KReBlnx4rfkPvskcaCppY4VnbVNBMXBHGwUOq6_fVPOBV12skMLSFyg3XPPL5j2c1y_VjD7JdEBDRWXnH6idlosQW86J=w999-h749-no

acgKcJh3YsfzjqrZ2jBD6rSBikv7RelbuR3Hg5GEnWRsclFbWz48ffmF887Xf5p7QgB37GagZrkgX_42QuMkZrMXUr5nsHrGvSfP5YiznIznq5BVgwO4U8zBUITtKHN3lTyLVOll95QS_KPKbZo_vmDIKCI97JAzOrXgwJVlcJDP4femRpfhE1SNWKyXFco_2UGioA4QPpuzYeOK2Q9lTFoOKU0HiaZXL_jGjb0DFe2aucPp0e3jh-sFIBBgm7InxY0O6NkL0t6K_r4lz7sZ9B8OMm6T5GEcw1w_0V2bOHr5wvGBfSLlbR1UnUzzdSWMvouueRL2ZHhTtNUeSvd5OWMzjB5zI2zJIcp6Mnjpq5RDqjx5JuzTMA1kwJb8SnrYa5xZiUqEPf06bfbVBmfWeZLtW_U7d-AHtTuXQ5nG0rFiopap3rBScY4tCmT6cxNYsWLXxiwXHDlLFEet_4RxiPzRLYQxhARtUhGXGjzW5-KzAsvUOiyrmnODbxMPyuqSSMXbmyNO10FqQpiZ7QW6rpNcyMQvgj0zSibyM-6OlDBchKd1VgXj0GFRKhPJMyhMJg8dQHJuebfZFh6uffjhYvknkbF44z10htZBqw24v5rdNADKh4_anuhIS5dqK3IDbXIJAjWdSoa78IclvFH7F4UkABO30RVNKLIK8NzLeV_lIXkyYKzlfmahYPGF=w999-h749-no
 
Sadik,

It really looks very well organized and professional.
Do you made reverse schematic of this slow start module? I am interested on it and would like to know detail from users. The Chinese support is terrible – no details, no answer to question and no schematics.

I suppose it uses NE555 as ON - OFF memory device.
I would like to know the function of the opto couple that appears on the board near to ON-OFF connetor. I suppose it is related with temperature protection which you are not applying.

Regards
 
Sadik,
Do you made reverse schematic of this slow start module?
I suppose it uses NE555 as ON - OFF memory device.
I would like to know the function of the opto couple that appears on the board near to ON-OFF connetor. I suppose it is related with temperature protection which you are not applying.
The slow start module probably needs its own power lines, cannot see them on the picture.
Does your amplifier have both a double main switch and 2 relays for the main transformer?
 
The slow start module probably needs its own power lines, cannot see them on the picture.
Does your amplifier have both a double main switch and 2 relays for the main transformer?

The soft start board showed in the picture has a small power transformer as its own power supply. This is the stand by power suply connected directly to mains.

The 2 relays in the board works in the live ac line. The first relay activate the main transformer with 4 NTC in serie in such a way to limite surge start current. The second relay connect the power line directly to the main transformer.

My question is related to the control and protection circuit on this board.

Regards
 
Sadik,

It really looks very well organized and professional.
Do you made reverse schematic of this slow start module? I am interested on it and would like to know detail from users. The Chinese support is terrible – no details, no answer to question and no schematics.

I suppose it uses NE555 as ON - OFF memory device.
I would like to know the function of the opto couple that appears on the board near to ON-OFF connetor. I suppose it is related with temperature protection which you are not applying.

Regards


I bought this module online from Soft Start Module with Thermal protection - Dual Sensors

The slow start module probably needs its own power lines, cannot see them on the picture.
Does your amplifier have both a double main switch and 2 relays for the main transformer?


I think everything is included in soft turn on board. I just have to make connections from the main line & to the transformer thats it. More details can be found on the link which i shared above.


Nice work, what is the heatsinks?
Where you buy these?


These heatsinks are available in India. I purchased from stockist named "Akash Enterprise" Product Code: K 300 | Akashheatsink.com