I’d like to expand my electronics testing ability on the bench, but the cost of even a used distortion or spectrum analyzer is beyond what I can justify at this time. So, I’m looking at PC based options, which look fine for line level (or other low voltage) use, but I want to be able to test performance of power amps, smps, etc. in the audio range. I understand the shortcomings of a PC based approach here- at least I think I do.
This leaves me looking at ways to reduce voltage without introducing distortion in the process. I think I have three options here, but would like some opinions on which is best, or better options.
1) Voltage divider. I have a blank dual gang stepped attenuator, which I could populate with whatever resistors, but I understand that there may be nonlinearity with this arrangement. Can I just use a 1M ohm input impedance when I build it? I’m not sure.
2)Build or buy a buffer. Not sure what the best options are here. I’m not against building if I can be sure it will work well. IOW, I don’t want to design it, since I might screw it up.
3) I noticed that my Hitachi oscilloscope has a “trigger signal out” where I can send the signal being used to trigger the scope (eg channel 1, etc.) to an outboard device. I think this might allow me to use the scope itself as a buffer. Would it be a clean source? I’m not sure about this either.
Any and all thoughts are appreciated including, “Hey dummy, just do this, because it will work great and is dead simple.”
Thanks
Full Disclosure: I'm cross posting this at AK, too.
This leaves me looking at ways to reduce voltage without introducing distortion in the process. I think I have three options here, but would like some opinions on which is best, or better options.
1) Voltage divider. I have a blank dual gang stepped attenuator, which I could populate with whatever resistors, but I understand that there may be nonlinearity with this arrangement. Can I just use a 1M ohm input impedance when I build it? I’m not sure.
2)Build or buy a buffer. Not sure what the best options are here. I’m not against building if I can be sure it will work well. IOW, I don’t want to design it, since I might screw it up.
3) I noticed that my Hitachi oscilloscope has a “trigger signal out” where I can send the signal being used to trigger the scope (eg channel 1, etc.) to an outboard device. I think this might allow me to use the scope itself as a buffer. Would it be a clean source? I’m not sure about this either.
Any and all thoughts are appreciated including, “Hey dummy, just do this, because it will work great and is dead simple.”
Thanks
Full Disclosure: I'm cross posting this at AK, too.
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(not really)
. This got me thinking about the fact that the front panel jack on my creative audigy II zs platinum pro has an attenuation knob- now I'm wondering if it too will take higher voltages similar to the tascam mentioned (about 21v). I'll need to look later...