For the heck of it and waiting till I perhaps fan find a hamfest that are selling real Tek probes, I got some chinaprobes to see how bad they were. These are "100MHz" 10/1:1 probes. I suppose I can keep them with my old VuData 20MHz, but wanted to see how bad they really were for my 300MHz Tek.
Wow, not sure what to say about them. Perhaps I'm expecting too much and expecting the pink unicorn. And perhaps not an banana to banana comparison:
From top to bottom are ch.1 to ch.4, and ch.1/ch.2 have full attenuators (set to DC coupling) with the cheap probes switched 10:1. Ch.3 and ch.4 have DC coupling only. Ch.3 has a RG174 with alligator clip wires and no attenuation. Ch.4 is a 1.5" piece of solid wire from the calibrator output to the input. (BTW, bottom of the screen are the attenuations for the 4 channels and the time/division. Top of screen is trigger source, trigger voltage, and time between cursor marks).
Now I would guess that since all of the connections, especially the 4 ft of RG174U would add quite a bit of cap, but even if I disconnect it, the waveforms don't change that much, but it is noticeable. The two scope probes if disconnected do not affect the display at all, implying perhaps the 10:1 really is working.
What I'm wondering is if the bad ringing should be tunable or perhaps that's the way it should be (I don't know how good the calibrator output should look.) The probe compensation adjust seems to be simply attenuating the signal and not affecting the ringing (I suppose the attenuation is not unexpected, after all, it is a short at high frequencies.)
Am I using them all wrong, or is this what I get for having bad chinaprobes?
And here's one of the probes on my Vu-Data using its probe calibrator:
This time I guess it's clearly overcompensated/overdamped. Perhaps I'm running the Tek's calibrator a bit too fast? (Note poor Vu-Data is in chop mode...)
BTW: I hate these cheap chinaprobes hooks. Every other hook I have is really "thin" - these hooks in these probes are really thick, making it probably impossible to hook onto through hole IC pins. The other spring hooks I have are "thinner"...
Wow, not sure what to say about them. Perhaps I'm expecting too much and expecting the pink unicorn. And perhaps not an banana to banana comparison:
From top to bottom are ch.1 to ch.4, and ch.1/ch.2 have full attenuators (set to DC coupling) with the cheap probes switched 10:1. Ch.3 and ch.4 have DC coupling only. Ch.3 has a RG174 with alligator clip wires and no attenuation. Ch.4 is a 1.5" piece of solid wire from the calibrator output to the input. (BTW, bottom of the screen are the attenuations for the 4 channels and the time/division. Top of screen is trigger source, trigger voltage, and time between cursor marks).
Now I would guess that since all of the connections, especially the 4 ft of RG174U would add quite a bit of cap, but even if I disconnect it, the waveforms don't change that much, but it is noticeable. The two scope probes if disconnected do not affect the display at all, implying perhaps the 10:1 really is working.
What I'm wondering is if the bad ringing should be tunable or perhaps that's the way it should be (I don't know how good the calibrator output should look.) The probe compensation adjust seems to be simply attenuating the signal and not affecting the ringing (I suppose the attenuation is not unexpected, after all, it is a short at high frequencies.)
Am I using them all wrong, or is this what I get for having bad chinaprobes?
And here's one of the probes on my Vu-Data using its probe calibrator:
This time I guess it's clearly overcompensated/overdamped. Perhaps I'm running the Tek's calibrator a bit too fast? (Note poor Vu-Data is in chop mode...)
BTW: I hate these cheap chinaprobes hooks. Every other hook I have is really "thin" - these hooks in these probes are really thick, making it probably impossible to hook onto through hole IC pins. The other spring hooks I have are "thinner"...
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