Shouldn't the power transistors get a bit warm after a few hours use. These do not.
Is there a way te measure output power with a dim?
The output transistors should be warm after use.
You can't measure power output with a bulb tester in place. You need to be sure the amp is OK and then play a sine wave test tone (use a low frequency such as 400Hz as all DVM's should be OK with that) while measuring the AC voltage across a dummy load.
Is the output stage drawing current ? Voltage across the 0.1 ohms with no signal and no speaker attached.
You can't measure power output with a bulb tester in place. You need to be sure the amp is OK and then play a sine wave test tone (use a low frequency such as 400Hz as all DVM's should be OK with that) while measuring the AC voltage across a dummy load.
Is the output stage drawing current ? Voltage across the 0.1 ohms with no signal and no speaker attached.
Hey, thanks for the info. Have been running them without the dim bulb.
Could you please dummy it down a bit? Explain exactly how I should this voltage reading.
I will have dummy load next week. I don't own an osicilosope or a signal generator. Can I send the 400 Hz test tone to the amp utilizing a MP3 or some other player?
Yes, you can easily make test tones using Audacity and an MP3 file is perfect. Make sure to use a volume control in front of the power amp... don't just feed it with a full level signal.
http://www.diyaudio.com/forums/soft...ing-using-audacity-get-you-started-guide.html
Your meter needs to be set to AC volts and placed to measure across the speaker terminals. A reading of around 22 volts AC would correspond to 60 watts RMS into an 8 ohm load.
You need to avoid driving the amp to hard and for to long. One method is to set the AC output voltage first and with no load attached. Set it to say 5 volts AC initially. Then briefly connect the load across the terminals. The reading shouldn't alter... in other words the amp should maintain its output. Then work your way up.
Full power testing of an amp is stressful in terms of heat produced so keep the time with a load attached very short... no longer than needed to take the reading.
http://www.diyaudio.com/forums/soft...ing-using-audacity-get-you-started-guide.html
Your meter needs to be set to AC volts and placed to measure across the speaker terminals. A reading of around 22 volts AC would correspond to 60 watts RMS into an 8 ohm load.
You need to avoid driving the amp to hard and for to long. One method is to set the AC output voltage first and with no load attached. Set it to say 5 volts AC initially. Then briefly connect the load across the terminals. The reading shouldn't alter... in other words the amp should maintain its output. Then work your way up.
Full power testing of an amp is stressful in terms of heat produced so keep the time with a load attached very short... no longer than needed to take the reading.
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