| Author | Views | Views Today | Rank | Comments |
| 85,408 | 4 |   |
33 |
| Author | Views | Views Today | Rank | Comments |
| 85,408 | 4 | |
33 |
| This nifty sound level meter is a perfect one chip replacement for the standard analog meters. It is completely solid state and will never wear out. The whole circuit is based on the LM3915 audio level IC and uses only a few external components. This circuit can also be integrated into audio amp projects. |
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| 1N491 diode is not available here. can you give me another as a substitute because the circuit doesn't work. i just used 4148 diode. is it ok? pls response.. tnx! | ||
| I have just built this project and i can't seem to get it to work. The problem is there are some many errors I could make here. I have a feeling it is either the PnP transistor, or the Silicon Diode. If u can help me out, plus email me. | ||
| looks nice but when i turn the power on all LEDs glow bright too, anyone knows how to fix it? thanks | ||
| Thanks for the circuit works well | ||
| It works. Used 100k pot for R4. | ||
| Thanks for the site, though im having a few problems with this circuit. I have tried making a stripboard of it and now just tried a PCB. WIth each, all of the LEDs light brightly when the voltage is supplied. Putting an audio signal in makes no difference. Any help would be appriciated, cheers. | ||
| The circuit will work with any little PNP transistor. The old version of the project doesn't work. | ||
| i'm finding it difficult to get the transistor so pls send me the circiut diagram of the older version | ||
| PLEASE help me to get dB METER for 0 - 150 dB, Thanks. | ||
| I have not built circuit but for those who say it doesn't work may need some audio signal info. Pro-Audio vs Consumer Product Audio line levels are different. Consumer product line standard outputs is -10dBv = .316 Vrms = 0.9 Vp-p. ProAudio line outputs is 1.78dBv = 1.23Vrms = 3.47 Vp-p. So this circuit is more appropriate for cheap consumer products to monitor RCA outputs. You should consult your equipment for actual output levels. e.g. Tape monitor output on my stereo is .150 Vrms and VCR output is 1.0 Vp-p and my mixer line outputs is 1.55 Vp-p when controls are at 70%. Looking at the circuit I would think the right diode would be important. Don't regular silicon diodes drop .7v when forward biased. | ||
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