- Dead LED TV restored back to life. Model: Fuji Japan
- 50″ LED TV Display Problem Repaired
- LED TV That I’m Not Able To Repair
- Shorted LED Lights In An LED TV Repaired. Model LG
- LED TV T-Con Board Problem
- 471k MOV Cracked In LED TV Repaired
- Flash Rom IC Caused Standby Problem in LED TV
- LED TV No Sound Repaired
- No Display In Samsung 32″ LED TV Repaired
- No Power In LED TV Solved
How To Repair Amplifier No Sound
A customer of mine brought to me the TAC Integrated Stereo Power Amplifier With the Model of AV-355 for repair. The complaint was no sound but have power. Usually the first thing I do was to connect a speaker at the output jack to see if the sound really not present.
Another test is to check the output DC voltage at the speaker output jack. It should not have DC voltage and from the test I got 35.6 DC volt which mean the internal power transistor had already shorted.
Alright, once the casing was removed I could see two circuit boards (main and pre amp) and a big toroidal transformer-see the photo below:
From the visual inspection, I found two e-caps bloated on top of the capacitor casing, broken jumper wires and a burnt resistor-look at the white arrows in the photo below:
I knew if a burnt resistor were found this means the main power amplifier transistor will be shorted. True enough, when I placed my digital multimeter to the transistor pin (on board) I got very low ohm on all the legs (pins). From experience, once you have found a shorted power transistor, you have to check all related components around that circuitry. If you want to learn how to accurately test electronic components you can check out Jestine’s Ebook HERE.
After spending some times to check the circuit board, I can’t believe that there were actually 15 bad components found which include the burnt resistor.
After the replacement with new components the stereo power amplifier with no sound problem was finally fixed. I did not post the video thus you would not hear the sound but the sound worked!
This article was prepared for you by Suranga Bandara who owns an Electronics repair shop in Anuradapura, Sri Lanka.
Please give a support by clicking on the social buttons below. Your feedback on the post is welcome. Please leave it in the comments. If you have electronic repair articles to share with us, please contact us HERE.
P.S- If you enjoyed reading this, click here to subscribe to my blog (free subscription). That way, you’ll never miss a post. You can also forward this website link to your friends and colleagues-thanks!
Note: You may check out previous post about fixing active speaker in the below link: