139 SANSUI AU-717 UNA RIPARAZIONE COMPLESSA #elettronica #audio #vintage

https://www.pcbway.com YOUR TRUSTED PARTNER In this video, I show you how multiple faults can develop in different sections of a vintage hi-fi amplifier. Follow me on this new adventure and see what I can do for you @theriverlab Here you can find the digital oscilloscope with multimeter function and signal generator at a discounted price: https://www.fnirsi.com/products/2c53t... Enter this discount code, which is valid on the entire catalog, including other products: THERIVERLAB 6% OFF Do you like the channel and want to make a PayPal donation? Use the link below: https://www.paypal.me/theriverlab Subscribe to the YouTube channel for numerous benefits:    / @theriverlab   Subscribe to the Patreon channel:   / theriverlab   00:00 Video Start 01:11 Device Presentation and Disassembly 02:57 Internal View 03:38 Preliminary Test 06:59 Screen Removal 08:35 Phono Input Explanation 1 11:17 Oscilloscope Test 13:08 Replaced Transistors 13:43 Test After Transistor Replacement 15:13 Preamplifier Explanation 2 17:51 Some Measurements on the Preamplifier 19:01 Measuring the Resistors 22:01 Replacing Resistors 22:26 Testing with Oscilloscope 10:55 PM Power Amp Section 11:26 PM A Blown Fuse 11:49 PM Disassembling the Power Amp 11:07 PM Disassembling the Power Amp 12:42 PM Testing the Transistors 13:13 PM Thermal Paste and Reassembling the Transistors 15:08 PM Reassembling the Boards 15:48 PM Cleaning the Switch 15:14 PM Testing the Function 15:39 PM Offset Check 15:54 PM Bias Check 15:40 PM Bias Adjustment 15:00 PM Tone Check 15:49 PM Power and Distortion Measurement 15:53 ​​PM Reassembly 15:45 PM Conclusions