Hi,
Here by my most useful project of 2019 yet.
It’s a bit quick and hot snot, but it has color-coded strain relieved silicone wires with pins which are very easy to handle.
Couldn’t find other examples on Google hence I post mine for inspirational purposes.
Bye
This is limited to low frequency, This thing will add noise and inductance to any fast thing
Doesn't work with the grounds, but so long as you're not bending the probes, you can take off the hook clip tip and just plug the pointy tip into most solderless breadboards. The length of those wires will add a lot of ringing to a fast signal, though, as they will act like antennae for other signals as mentioned.
User tggzzz's (here)'s web site entertaininghacks, has good stuff on the probe issue.
Also Bob Pease..
I bet you could improve that a lot while keeping the convenience aspect of it. Check out Bob Pease's low inductance probe holder ideas.
This is limited to low frequency, This thing will add noise and inductance to any fast thing
I know it has its limits, so does a breadboard
. Would thin shielded wires make it better suited for high frequency or does it really need 50 ohms (impedance?).
Nice colors too!
On ali express those dupont cables come in a 20cm silicone variant to. i really like them.
A breadboard is probably only good up to about 10MHz anyway, so I don't feel like these sorts of make-shift probe hacks represent a huge problem as breadboarding, almost by definition, means you aren't working w/ high speed signals.
For my use I made some even hackier solutions from some
cheap and cheesy probe cables that I terminated in dupont pins for quick probing of test points on projects being breadboarded. Both ends are color coded with heatshrink to match the scope trace colors:
Doesn't work with the grounds, but so long as you're not bending the probes, you can take off the hook clip tip and just plug the pointy tip into most solderless breadboards. The length of those wires will add a lot of ringing to a fast signal, though, as they will act like antennae for other signals as mentioned.
That is some good advise, the tip is indeed thin enough.
I can support the probes by hanging them at my fumextracter, which embeds also my workspace light.
One inspirational aspect of this DIY extracter is, that it only turns on when the iron is taken of the stand. It is supported by a very sturdy monitor arm. So it is also easy to push it out of the way.
A breadboard is probably only good up to about 10MHz anyway, so I don't feel like these sorts of make-shift probe hacks represent a huge problem as breadboarding, almost by definition, means you aren't working w/ high speed signals.
For my use I made some even hackier solutions from some cheap and cheesy probe cables that I terminated in dupont pins for quick probing of test points on projects being breadboarded. Both ends are color coded with heatshrink to match the scope trace colors:
Very nice and cheap solution!
Would a signal generator be a good way to benchmark different cable solutions? I’m thinking of buying a better one. ( I have one at my low end Picoscope, which just has been made obsolete)
You should not use 50ohm coax cable for high impedance oscilloscope inputs. Probe cables use special high impedance (low distributed capacitance) coax with very thin wire.
If not, you are limited to very low frequency (<1MHz)
A breadboard is probably only good up to about 10MHz anyway, so I don't feel like these sorts of make-shift probe hacks represent a huge problem as breadboarding, almost by definition, means you aren't working w/ high speed signals.
For "digital" signals the
only thing that matters is the risetime; the period is
completely irrelevant.
If you want to think in anthromorphic terms, the wires don't know when the next transition is coming.
If you want to understand the theory, consider how to construct a square wave from harmonically related sine waves.
If you want
a set of measurements, see
https://entertaininghacks.wordpress.com/2018/05/08/digital-signal-integrity-and-bandwidth-signals-risetime-is-important-period-is-irrelevant/ Then realise that modern jellybean logic can have 250ps transition times and harmonics into the GHz.
Hi, after one of the suggestions above I did visit your website. Very informative.
The solution from LUMA looks more practical. I use (for example) Pomona BNC(f) to grabber adaptors, which i modified with 0.64sq. or Mil #22D pins.
The things I realy like about my solution is that it only has one ground wire, so no mistakes there. And because the pcb lies stable on my desk, very light, thin and flexible cables move only a bit when probing, so my cluttered desk doesn’t get disturbed much
.
The things I realy like about my solution is that it only has one ground wire
That can, of course, also be a weakness when you consider the extra loop area and inductance. It depends on what you are trying to measure and ignore.
I’ve got a signal generator on order, so I will certainly do some experimenting later on. Better understanding of probing means also a better understanding of signal behavior in circuits I quess.
I like these. I would recommend the ones that use little bits of PCB be some how insulated and that you add a thing on them so the wires bend on a strain relief and it is linear rather then having a 90 degree bend on a floppy PCB.
A very nice option for a multimeter might be to get some pamona brand multimeter probe jacks and attach a pin to them, so they can be inserted into the PCB and the multimeter can be inserted into the probe jack.
those probe jacks are really really nice.
They have both banana cable jacks, and jacks that actually accept your multimeter's probe tip in a small collet <1mm.
similar & cheap
https://www.amazon.com/Multimeter-Probe-Binding-Banana-Panel/dp/B0113IH0IW
I’ve got a signal generator on order, so I will certainly do some experimenting later on. Better understanding of probing means also a better understanding of signal behavior in circuits I quess.
And your first experiment will lead you to question whether what you see on the screen is a function of:
- the scope
- the sig gen
- experimental technique, including probing
or all three
The specifications will be of paramount importance, particularly what they
omit guaranteeing
See my .sig about DACs.
My Siglent SAG1021 arrived and did some testing directly at its outputs, here are the (to my surprise) results at a 1 Mhz 4 VPP square wave:
- Using hookprobe and clip: obvious ringing
- Using probetip and gndspring attachment: no ringing
- Using hookprobe and clip via breadboard probing setup: obvious ringing
- Using probetip and gndspring attachment via breadboard probing setup: no ringing
So my conclusion would be for the moment: The probe clipwire introduces ringing. The breadboard probing setup also, but might be clear of ringing if clip isn't used in the the ground connection.
I don't understand it at all!
15 min later....., it seems that the ground clip/wire of my used probe isn't conducting at all! (Tested that) My other probes don't ring in any of the above conditions.
So the verdict is that this setup isn't to bad in respect to ringing.
In that respect I had the following results using the sync pulse of the generator:
- Probe with spring directly: 2 ns up 2 ns down
- Probe with spring via “breadboard probe pins”: 3 ns up 3 ns down
- Probe with hook via “breadboard probe pins”: 3.6 ns up 3.6 ns down
- Probe with hook direct: 3 ns up 3 ns down
- BNC cable Siglent: 2.6 ns up 2.2 down
- BNC cable 3 party: 12.2 ns up 10ns down
Conclusion: better than my 3 party BNC cable. And very near what I can measure with my scoop. Much better than my signal generator can do (23 ns) on square wave.
To my understanding I measured the capacitive properties of the setup this way? I should mention, because these rises where faster I saw a bit of ringing.
Photos of the experimental setup and scope screen would help; the devil is in the details.
I'd take a few digital pictures, reduce the resolution to 640*48 (or so!), and use the "+Attachments and other options" option when composing or modifying a posting.
Below are some screenshots. Because signal was very repetitive I used averaging mode.
Rise and fall changed with vertical range a bit, prop. because of the resolution.
