Technically it is tomorrow I guess. Found the issue with the sound card, it was the driver. Took me many hours of frustration to find it. Back to M-Audio card as it has a lower noise level in this set-up.
Taken at 48000, 65536FFT Blackman. 0dB = 1Vrms
Taken at 48000, 65536FFT Blackman. 0dB = 1Vrms
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I agree as it makes perfect sense, but the only real difference between the good and bad was the software.dll used for the signal generation. I was able to repeat the same results and symptoms this morning.
Why is the third harminic so dominant?
I ask this as I have the RIAA hooked up right now. I don't see sidebands to the signal but I do see 60,120,180..... with the odd harminics spraying up into the higher freqs.
Why is the third harminic so dominant?
I ask this as I have the RIAA hooked up right now. I don't see sidebands to the signal but I do see 60,120,180..... with the odd harminics spraying up into the higher freqs.
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How much of the issue could be related to incoming power quality? Just put my probe on the AC line-in and it looks like a triangle wave with the tops and bottom cut off tp fit it into 120V.
When I look at the harmonic spectrum closer it kind of looked like a triangle spectrum.
When I look at the harmonic spectrum closer it kind of looked like a triangle spectrum.
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You did not have such a harmonic noise with so high a fundamental before in any of your measurements. Something weird is going on. If you check your DC rails with the scope are they still a flat line? If your mains are a triangle indeed the field around the Tx must be terrible on the other hand.
I am trying to find a couple of batteries to take a picture from the scope. With kids and a Wii that is almost impossible. I could hear a wierd hum this morning, very faint but there.
Force Out is dead quite on the shunt per the scope.
I may try pulling the tranny out and moving it across the room.
Force Out is dead quite on the shunt per the scope.
I may try pulling the tranny out and moving it across the room.
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Hi,
is post4530 direct off the mains supply?
Note the odd harmonics are consistently higher than the even harmonics.
The tops chopped off is standard with our mains. Many consumers only draw current from the mains when the waveform is near maximum voltage.
Transformers feeding capacitor input filter.
SMPS that use a capacitor direct to rectified mains voltage do the same.
Changing the shape of the mains waveform from true sinusoidal to a flattened waveform can be recreated by introducing harmonics to extremely high frequency in the correct proportion and in the correct phase.
It's these harmonics in the mains supply that are the cause of many of our PSU problems.
is post4530 direct off the mains supply?
Note the odd harmonics are consistently higher than the even harmonics.
The tops chopped off is standard with our mains. Many consumers only draw current from the mains when the waveform is near maximum voltage.
Transformers feeding capacitor input filter.
SMPS that use a capacitor direct to rectified mains voltage do the same.
Changing the shape of the mains waveform from true sinusoidal to a flattened waveform can be recreated by introducing harmonics to extremely high frequency in the correct proportion and in the correct phase.
It's these harmonics in the mains supply that are the cause of many of our PSU problems.
Power line before the IEC looks the same.
Little different subject, but following through on a promise. Here is the turntable in action with the DL103R, Magnapan Unitrac I arm.
Better get the stuff of the camera before these are stolen as well!!!!
Little different subject, but following through on a promise. Here is the turntable in action with the DL103R, Magnapan Unitrac I arm.
Better get the stuff of the camera before these are stolen as well!!!!
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