Sure. You can try the oscillator on your XP machine.
You can open the folder on the CD with your file manager. Click on the folder Application GUI. In that folder there is another folder named X86. Try that version of the build. it will run as a 32 bit app on a 64 bit machine.
Work in progress - status:
Ok I will try that. I am running your osc from the XP and running the Audio-Prec from the WIN8 machine.
So far I learned the 2H can be as low as -135dB with 3H at -138dB (1KHz). These are very good numbers. Also, there is very short settling times for all freq including low freqs.
The distortion is a little higher on some ranges... something for you to look at, perhaps.
I'll get more info to you by regular email until the prototype is the way you like it.
THx-RNMarsh
1KHz
1KHz and 5KHz
Ok I will try that. I am running your osc from the XP and running the Audio-Prec from the WIN8 machine.
So far I learned the 2H can be as low as -135dB with 3H at -138dB (1KHz). These are very good numbers. Also, there is very short settling times for all freq including low freqs.
The distortion is a little higher on some ranges... something for you to look at, perhaps.
I'll get more info to you by regular email until the prototype is the way you like it.
THx-RNMarsh
1KHz
1KHz and 5KHz
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Comparing to resistive tuning the Mdacs seem to exhibit a slightly higher distortion depending on the output current of the dacs. When the dacs are closer to their extremes the distortion
decreases. Therefore for the same frequency and different range overlap the distortion may be different.
I do observe distortion differences in different range overlapping with other oscillators.
339A for example.
Another possibility is that if you're at the residual of the analyzer the sum-difference of phase of the harmonic between oscillator and analyzer might be showing their face. ther can be phase differences between same frequency in different ranges.
decreases. Therefore for the same frequency and different range overlap the distortion may be different.
I do observe distortion differences in different range overlapping with other oscillators.
339A for example.
Another possibility is that if you're at the residual of the analyzer the sum-difference of phase of the harmonic between oscillator and analyzer might be showing their face. ther can be phase differences between same frequency in different ranges.
Very low distortion --
Here is the FFT of 2H and 3H on the 100Hz range but still 1KHz.
I noticed something.... at levels far below -100dB the noise is beginning to have its affect.... namely, that the A-P doesnt always recognize a small change in osc freq. If I just change 1000 hz by +/- 3 hz, the AP may not track it and the Harmonic level being shown can go up .... using the 3H first. But sometimes, both can be up a lot more than is real. So, gentle people, we are near the measurement limits for accuracy.
What you see is from my 'bumping' the A-P notch filter back and forth until it was stuck at the center of the osc freq and thus the lowest distortion results.
Thx- RNMarsh
Here is the FFT of 2H and 3H on the 100Hz range but still 1KHz.
I noticed something.... at levels far below -100dB the noise is beginning to have its affect.... namely, that the A-P doesnt always recognize a small change in osc freq. If I just change 1000 hz by +/- 3 hz, the AP may not track it and the Harmonic level being shown can go up .... using the 3H first. But sometimes, both can be up a lot more than is real. So, gentle people, we are near the measurement limits for accuracy.
What you see is from my 'bumping' the A-P notch filter back and forth until it was stuck at the center of the osc freq and thus the lowest distortion results.
Thx- RNMarsh
Yes, if talking about THD+N.... A-P spec says it is 'typically' less than -115dB.
David's software frequency control panel via USB. ->
THx-RNMarsh
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Good Stuff!The counter (which is used for the coarse notch frequency tuning, usually) will stop working correctly at very low levels. The auto-tuning might still track the signal frequency, but as it tunes further from the nominal frequency, the distortion increases. That's probably a result of the used multiplier--I don't know what they use.
Samuel