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Unfortunately you all failed the test! The right answer is SOURCE IMPEDANCE! Now I will rename ASR to A_R, not much science to be found here. ... bye and good luck!

The green eye-pattern from the Siglent is well-known from telecom as an example of phase modulation that is common in satellite and terrestial systems, 16PSK in the picture. It's used in all (GSM and up) mobile phone systems and is "somewhat demanding" to get to grips with. Nasty combination of...

It's encouraging that some of you (but not all) think that cables influence AC millivolt measurements. What I miss are some important facts that also play a big part in the accuracy. There are simple methods to find out how close to the truth you are. The specifications are just as useful as...

I can recommend Visual Analyser for audio tests, freeware with lots (too many?) features. Seems to have connections with education (University of Rome) so there are lots of parameters in signal processing at that level. The settings mirror that but the easier default settings go a long way...

Yes, I agree and my use is also for "one off" measurements mostly. The ability to use soundcards as input/output with added math, FFT and other things is something I use. Datalogging of slow mulitichannel signals is another. If AC audio only is interesting search for "labview + soundcard" -...

I hesitate to say that "Bob's Your Uncle" again but then there is lots of share-ware virtual instruments to choose from. Signal Express was the other sw that is ready to run with just a litte bit of fiddling to see what the NI-DAQ instruments can do. I think the (huge) driver package is...

Yes, 16 separate channels with programmable gain in each channel. There are simpler ones with less "bells and whistles". It also has DA outputs and digital IO. Some NI software (free I think) makes a simple multichannel data aquicision system.

NI USB-6221 (National Instruments) 8 differential or 16 single ended inputs 16 bits, 250 kS/s Input range ±0.2 V, ±1 V, ±5 V, ±10 V Input impedance >10 GOhm in parallel with 100 pF ...then you "make" the instruments with any functions you need in LabView. Perhaps this is TOO digital for those...

No fancy button switches but still very good and getting more stable for each decade (time). (and I got a couple for free!) Can't find my Josephson junction that I got at the equivalent of NIST in Sweden. They made lots and only a few worked, a single unwanted atom ruined the show completely. A...

Perhaps ASR should be A(s)R since the "science" is sprinkled a bit unevenly across different areas. I wonder why this popped up when reading this thread? Robert Burns' Hog-Weighing Method: (1) Get a perfectly symmetrical plank and balance it across a sawhorse. (2) Put the hog on one end of...

If you try to measure an offset/bias voltage with a mix of test leads with different test clips connected to a cold iron chassies and a tinned copper lead on a hot emitter resistor you can forget fiddling with the last millivolts. Lots of small errors in the measured voltage that makes looking...

Yes, for DC the thermoelectric voltages in the leads gives an uncertianty of ALL the decimals if not every cable/test lead has exactly the same temperature. No touching with fingers or attaching test leads to stuff with even the slightest temperature offset like hot components. Microvolt AC...

Those who think that millivolt signals can be measured with the open test leads on DVM's won't be saved by some certificate in a drawer. It's simply a very bad method to measure low level AC with anything but shielded cables in the entire signal path. (and DVM's are rubbish at millivolt level...

The mechanical parts for a rotating table and the electronics seem to exist separately but seldom in the magical combinations you want. In mechanical workshops indexing tables are used in milling mashines to rotate the workpiece and DIY versions exist. The picture shows my own tiny prototype for...

If you tilt your proposed setup 90 degrees on it's side you have a wind speed measurement device and there is lots of windspeed under a drone. Lots of turbulence too. The worst place for a microphone really. Ultrasound is used in meterology instruments looking exactly like this. Spherical...

You would have a hard time to match all the sweeping statements here with the "science" word in the title of this forum. My prediction is you will never agree on anything simply because you are not anywhere close to making sense to outsiders (like me) . Aren't you all discussing just a tiny...

Many of you seem to connect "live music" with PA-systems and whatever acoustic environment you happen to be in. Then you must solve "equations " with many unknown factors to find out if what you hear is worthy of setting the standards for other listening. It's easy to do the oppsite, listen...

Then you must glean some more in other places! You might be surprised how many other uses an equailiser can have. Just now mine is making The Rosenberg Trio appear in my speakers just as I like it.

Tiny space but lots of tools and instruments. The IO board of a NAD 3400 in for major surgery. Noisy or non-functional swithches opened and cleaned. The contact elements are hidden inside the plastic parts so no chance of proper cleaning from the outside. New op-amps, relays and capacitors in...