How To Match Output Transistors In Audio Amplifiers : A Cheap DIY Output Transistor Tester

Video Description

This video came from a requirement i had to find suitable replacement transistors for a 1200W Audio Amplifier. Can we just replace the faulty ones or do we need to replace all the output transistors? Well that depends on how well the replacements match the original ones but measuring that is not as straight forwards as it might seem... Chapters 00:00:00 The Problem 00:03:05 Common Misconceptions 00:09:37 Why We Need To Match Transistors 00:10:15 Quiescent Current 00:11:34 All NPN Output Stages 00:15:12 Just Use A Component Analyzer? 00:22:10 No We Can't Because... 00:25:05 CHEAP DIY Power Transistor Tester 00:27:40 Testing The Tester 00:33:10 Conclusion Mentioned in this video https://sound-au.com/project177.htm 👉Click the link https://s.click.aliexpress.com/e/_EGDhRKk or enter the search code [AY4RYX] on the AliExpress homepage to find the latest money saving coupon codes or simply enjoy extra savings with the exclusive discount codes below, just for fans like you! 🌟 Remember, these codes can be used on almost all items in selected countries on AliExpress. IMPORTANT CHANGE: 📱 Previous phone categories were NOT available, but NOW phone categories ARE AVAILABLE in this new campaign! Codes valid until 4th December 2025 $3 off on orders over $29:【IFPOOKAP】 $6 off on orders over $59:【IFPHZLEC】 $9 off on orders over $89:【IFP1J3FV】 $16 off on orders over $149:【IFPG2Y76】 $23 off on orders over $199:【IFPLHKXC】 $30 off on orders over $269:【IFP1IPLR】 $40 off on orders over $369:【IFPZALA5】 $50 off on orders over $469:【IFPYSX48】 $60 off on orders over $599:【IFPQMQKT】 $70 off on orders over $699:【IFPQBIB1】 For All Your PCB needs: free $5 discount coupon https://www.pcbway.com/setinvite.aspx?inviteid=561767 Equipment used in my videos. These are affiliate links, you pay the normal price and I make a small commission. DM40C https://s.click.aliexpress.com/e/_c4q1dFy7 Aneng AN870 (Same as Zoyi ZT219) https://s.click.aliexpress.com/e/_oEInroF Zoyi ZT-DQ02 https://s.click.aliexpress.com/e/_oB2u3sT WinAPEX 268B Clamp Meter https://s.click.aliexpress.com/e/_opJTjEP VC480C+ MILLIOHM METER https://s.click.aliexpress.com/e/_onE0FaJ MESR-100 ESR METER https://s.click.aliexpress.com/e/_oombcej XC6013L CAPACITOR METER https://s.click.aliexpress.com/e/_omnOxub FNB58 USB ANALYZER https://s.click.aliexpress.com/e/_oneOfzl 4KV Breakdown Tester https://s.click.aliexpress.com/e/_omKXmND LED Backlight Tester https://s.click.aliexpress.com/e/_oCRPzdl NI-210SC Curve Tracer https://s.click.aliexpress.com/e/_o2e0Par NI210SJ (cheaper option but watch my review) https://s.click.aliexpress.com/e/_oD60O0D PCI POST ANALYZER https://s.click.aliexpress.com/e/_oBATbCF FNIRSI 1014D SCOPE https://s.click.aliexpress.com/e/_okTKV4x NPS3010W 30V 10A PSU https://s.click.aliexpress.com/e/_oDuHLdl Nice-Power Dual 120V 3A PSU https://s.click.aliexpress.com/e/_okGvYQ7 HR1520 Pro Short Killer https://s.click.aliexpress.com/e/_c2RE3ToB KSGER T12 Soldering Station https://s.click.aliexpress.com/e/_omqBjWR AIFEN-A9 PRO Soldering Station C115/C210/C245/C470 https://s.click.aliexpress.com/e/_ongFBEJ C470 Soldering Iron & Tips https://s.click.aliexpress.com/e/_opm1OND https://s.click.aliexpress.com/e/_oDVNACf QUICK 861DW https://s.click.aliexpress.com/e/_ooW7QGR PROS'KIT SS-331H https://s.click.aliexpress.com/e/_omxB5H5 Sequre HT140 Hot Tweezers https://s.click.aliexpress.com/e/_opH6KS3 KADA 853B Preheater https://s.click.aliexpress.com/e/_opPOUgX FNIRSI SWM-10 Spot Welder https://s.click.aliexpress.com/e/_ooZey3t INFIRAY P2 PRO IR CAMERA + MACRO LENS https://s.click.aliexpress.com/e/_ootcxPv TOOLTOP ET13S THERMAL CAMERA METER https://s.click.aliexpress.com/e/_oprvuP9 ET13S MACRO LENS https://s.click.aliexpress.com/e/_ol9d8hh Trinocular Microscope https://s.click.aliexpress.com/e/_okJictD TOMLOV TM4K AF FLEX https://s.click.aliexpress.com/e/_oBirts7 TL866 II+ PROGRAMMER https://s.click.aliexpress.com/e/_ooTmryb NC-559-ASM FLUX https://s.click.aliexpress.com/e/_onMlHRD DESOLDER BRAID (I use size 8045) https://s.click.aliexpress.com/e/_onhlLkx HX-T100 SOLDER https://s.click.aliexpress.com/e/_o2DHwJH ESD-11 TWEEZERS https://s.click.aliexpress.com/e/_om2F4w3 Learn Electronics Repair is now on Discord! Come and join the fun, it's free. https://discord.gg/vam6YC8vwU If you would like to support this channel You can send donations https://www.paypal.com/paypalme/youtubeLER You can subscribe to Patreon https://www.patreon.com/learnelectronicsrepair Or you can click Join to become a channel member Thank you Richard