I need a better (cheap) probe(holder) for measuring signals on arbitrary devices

[Fsck]

At the risk of self promotion, I wanted to share some ideas:
...
Basically building a simple PCB that connects pogo pins at your custom spacing location to a standard 0.1" header and you connect your test gear to the header.   Custom probing PCBs could be built inexpensively to suit your own needs:

Don't worry about promoting good ideas If push-comes-to-shove you can say something about "eating my own dogfood" or "believing in what I promote"

More seriously, how well does/doesn't it work with scope probes that don't have pogo pins?
Ditto, if you can't use a 6" ground lead because of its inductance, and have to use a probe plus its ground spring clip?

depends on your creativity with the set up. it's painfully configurable so your ability to visualize the solution is the only limit to what angles you can probe from.
I'm not the most spatially aware so it takes me a bit to get the perfect setup.

[tggzzz]

At the risk of self promotion, I wanted to share some ideas:
...
Basically building a simple PCB that connects pogo pins at your custom spacing location to a standard 0.1" header and you connect your test gear to the header.   Custom probing PCBs could be built inexpensively to suit your own needs:

Don't worry about promoting good ideas If push-comes-to-shove you can say something about "eating my own dogfood" or "believing in what I promote"

More seriously, how well does/doesn't it work with scope probes that don't have pogo pins?
Ditto, if you can't use a 6" ground lead because of its inductance, and have to use a probe plus its ground spring clip?

depends on your creativity with the set up. it's painfully configurable so your ability to visualize the solution is the only limit to what angles you can probe from.
I'm not the most spatially aware so it takes me a bit to get the perfect setup.

My question is more about whether a non-springloaded probe point (or two!) can be held against a pin/track. Pogo pins are undoubtedly more compliant in that respect. I'm sure I can adequately position the probe in an x-y plane, but the z-plane is more critical.

[Fsck]

At the risk of self promotion, I wanted to share some ideas:
...
Basically building a simple PCB that connects pogo pins at your custom spacing location to a standard 0.1" header and you connect your test gear to the header.   Custom probing PCBs could be built inexpensively to suit your own needs:

Don't worry about promoting good ideas If push-comes-to-shove you can say something about "eating my own dogfood" or "believing in what I promote"

More seriously, how well does/doesn't it work with scope probes that don't have pogo pins?
Ditto, if you can't use a 6" ground lead because of its inductance, and have to use a probe plus its ground spring clip?

depends on your creativity with the set up. it's painfully configurable so your ability to visualize the solution is the only limit to what angles you can probe from.
I'm not the most spatially aware so it takes me a bit to get the perfect setup.

My question is more about whether a non-springloaded probe point (or two!) can be held against a pin/track. Pogo pins are undoubtedly more compliant in that respect. I'm sure I can adequately position the probe in an x-y plane, but the z-plane is more critical.

x-y is idiotproof, but getting the critical amount of z-axis stability is your problem. in general it's quite difficult to get it perfectly stable for me. I guess the question is how stable do you need it to be?

I can get my probing set up, but if you bump it, you'll need to restart.

[tggzzz]

x-y is idiotproof, but getting the critical amount of z-axis stability is your problem. in general it's quite difficult to get it perfectly stable for me. I guess the question is how stable do you need it to be?

I can get my probing set up, but if you bump it, you'll need to restart.

Drat. But I'm not surprised.

I'm still looking for something better than

or http://www.edn.com/ContentEETimes/Images/00PCB/cclad1f3.jpg

[Fsck]

I get solid, stable readings when I have it set up.

[dadler]

At the risk of self promotion, I wanted to share some ideas:

We built our own "probing pcb",build details found here: http://pcbgrip.com/blogs/blog/19160631-building-a-probing-pcb.   Basically building a simple PCB that connects pogo pins at your custom spacing location to a standard 0.1" header and you connect your test gear to the header.   Custom probing PCBs could be built inexpensively to suit your own needs:



In this picture you can also see a pogo pin (with head shrink) being held, with the test gear attached to the pogo.

If your looking to hold a probe, this is another option, which can be found here: http://pcbgrip.com/collections/fittings/products/probe-clamp

Thanks for posting this. I have seen PCBGrip posted before but could not remember the name.

I have been tempted to buy one of these kits a couple of times now, but I've had two reservations:

1) The kit pages on your site, while showing all components quite neatly, don't really demonstrate the various ways you can configure all the parts. The pictures just look like a whole bunch of parts. It's not obvious to me which kit is appropriate, because I can't really see it in action. Some actual action pics of each kit would really help.

2) (and this is more personal/subjective) I wonder if I would actually use the kit in practice, or if it will be more work than it's worth/take up more space than is practical. I have lots of various panavise bases and tops and for the most part they cover my PCB-holding needs well. I also have a cheap Aven PCB holder ( http://www.amazon.com/Aven-17010-Adjustable-Circuit-Holder/dp/B00Q2TTQEE/ ), but I almost never use it because of how high it holds the board. The awesome anodized parts of PCBGrip appeal to my nerd-self, but I fear the setup would be much too fiddly and I would be constantly adjusting it.

[PCBGRIP]

1) The kit pages on your site, while showing all components quite neatly, don't really demonstrate the various ways you can configure all the parts. The pictures just look like a whole bunch of parts. It's not obvious to me which kit is appropriate, because I can't really see it in action. Some actual action pics of each kit would really help.

Agreed, the kit pages how a lot of parts.  For each of the kit pages, there is a table on the page that shows the name and quantity of each part included in the kit.  If you click on the part name, it will take you to that individual part and show some pictures of the part in action.  But, we still need to show more parts in action - something we will work on.

2) (and this is more personal/subjective) I wonder if I would actually use the kit in practice, or if it will be more work than it's worth/take up more space than is practical. I have lots of various panavise bases and tops and for the most part they cover my PCB-holding needs well. I also have a cheap Aven PCB holder ( http://www.amazon.com/Aven-17010-Adjustable-Circuit-Holder/dp/B00Q2TTQEE/ ), but I almost never use it because of how high it holds the board. The awesome anodized parts of PCBGrip appeal to my nerd-self, but I fear the setup would be much too fiddly and I would be constantly adjusting it.

When I started building PCBs, I was building custom jigs made of various parts, including wood and springs.  I could not find a setup to hold the PCB and be able to hold other things too (like hold through hole components upside down while I soldered).  PCBGRIP is great at holding the PCB and 'something else'.  PCBGRIP uses a open source aluminium extrusion (OpenBeam), which accepts standard 3mm hardware.   That way, it is easy to attach what every you need to your setup, it addition to holding the PCB.  The hinge assembly allows you to rotate the PCB 360 degrees.  The PCB can be tilted.  Also, the height of work can be adjusted, by raising or lowering the hinge assembly on the 10mm stainless rod.  Here is an overview of the work height that can be accomplished http://pcbgrip.com/blogs/blog/18208587-work-height-and-position.   Here is a holder we designed to hold a Saleae logic analyzer, to give you an idea of how things can be attached to the OpenBeam:



The Saleae holder is available on Thingiverse here : http://www.thingiverse.com/thing:735911

[tszaboo]

Wouldn't it be simpler to just solder a small wire? Probably takes a lot less than trying to position some whacky probe holder.

My colleagues do this with sometimes 10-15CM wires. Signal integrity is a magic world.
I prefer soldering a small, 1-2mm hook. Best is a 1K resistor to SMA, SMA cable, BNC adapter scope, 50Ohm. 1:20.

[jadew]

Wouldn't it be simpler to just solder a small wire? Probably takes a lot less than trying to position some whacky probe holder.

My colleagues do this with sometimes 10-15CM wires. Signal integrity is a magic world.
I prefer soldering a small, 1-2mm hook. Best is a 1K resistor to SMA, SMA cable, BNC adapter scope, 50Ohm. 1:20.

Depends a lot on the frequency. For most things, a 1-3 cm wire will have no noticeable effect on the reading and you can easily connect with the oscilloscope probe to it. Slow digital signals are more forgiving and you can definitely get away with longer wires.

The SMA setup sounds interesting, but I'm having trouble imagining it, could you maybe post a picture?

[SArepairman]

Also, if you are making the boards yourself it is wise to include ground plane on top so you can do the oscope ground spring trick.

You wind a spring around a drill blank the same diameter as your probes ground shield, then solder that spring to some ground plane exposed on the top of the PCB. The center of your spring should be where you want to probe, so you just stick a probe in it and everything is held in place nice.

[tggzzz]

Also, if you are making the boards yourself it is wise to include ground plane on top so you can do the oscope ground spring trick.

You wind a spring around a drill blank the same diameter as your probes ground shield, then solder that spring to some ground plane exposed on the top of the PCB. The center of your spring should be where you want to probe, so you just stick a probe in it and everything is held in place nice.

There's also the very convenient commercial and homebrew techniques outlined in https://entertaininghacks.wordpress.com/2015/04/23/scope-probe-accessory-improves-signal-fidelity/

[Cortex]

I have just finished developing this great system for probing and injecting low power signals.
Quite cheap too.

https://www.ebay.ca/itm/High-Precision-Needle-PCB-Probing-System-Quick-Magnetic-Holders-Low-Profile/263447821265?autorefresh=true

Norm
Cortex R&D Inc
Quebec, Canada

[Neomys Sapiens]

I also collected all the small tip inserts for the Tek SMD probes which clumsy colleagues left wasted or simply lost and made pogo tip extensions and angular shifts out of them.

[ivaylo]

I have just finished developing this great system for probing and injecting low power signals.
Quite cheap too.

https://www.ebay.ca/itm/High-Precision-Needle-PCB-Probing-System-Quick-Magnetic-Holders-Low-Profile/263447821265?autorefresh=true

Norm
Cortex R&D Inc
Quebec, Canada

eBay says you don't ship to US, that right?

[Cortex]

Quote from: ivaylo on January 20, 2018, 06:41:19 PM

>Quote from: Cortex on January 20, 2018, 07:56:15 AM

I have just finished developing this great system for probing and injecting low power signals.
Quite cheap too.

>https://www.ebay.ca/itm/High-Precision-Needle-PCB-Probing-System-Quick-Magnetic-Holders-Low-Profile/263447821265?autorefresh=true

Norm
Cortex R&D Inc
Quebec, Canada

eBay says you don't ship to US, that right?

Yes, I do ship worldwide!  I made a mistake, and I've changed my listing since.

But now, I sell it as a kit because it takes too much of my time to assemble all of them.  But it's very easy and takes about an hour if you're not in a hurry.

BTW, I changed my design a bit, to include another thumb screw for the coarse boom vertical offset adjustment, and traded all Torx for more popular Philips screws.

* Also, if you want to bypass eBay, I can shave off about $5 CAD.

Email me directly if you're interested:  nd@ctrnd.com

Norm

[Muxr]

One of the things I worry about is shorting pins when measuring live circuits, it's incredibly easy to do in some cases (particularly on dense ICs, trying to measure individual pins) and can result in unexpected damage.

What I do if I need to measure delicate electronics, particularly if high bandwidth isn't important, I take some 30AWG wrapping wire (https://www.amazon.com/gp/product/B00GWFECWO/ref=oh_aui_search_detailpage?ie=UTF8&psc=1) And lightly solder the wire onto the test points I like to measure. I then hook my probes to the wrapping wire and turn on the device. This then gives me the full freedom of connecting as many DMMs (most of my DMMs have clip leads on them) as I want and as many scope probes I need.

[cdev]

@cortex seems to have relisted his little probe kit for a bit less than $50 and it actually looks quite competitive compared to similar products, IMHO.

Cortex, have you ever considered using mini coax, and including a grounding connection for the metal plate? If I bought something like that I would either expect it to have a grounded shielded probe or I would modify it afterward to use shielded probe wire. I tried to build something similar using mini coax, it remains in a semi unfinished state, I need some more parts.

I was using old drafting tools as the source for my parts. They are very cheap considering what they originally sold for.

[Cortex]

One of the things I worry about is shorting pins when measuring live circuits, it's incredibly easy to do in some cases (particularly on dense ICs, trying to measure individual pins) and can result in unexpected damage.

What I do if I need to measure delicate electronics, particularly if high bandwidth isn't important, I take some 30AWG wrapping wire (https://www.amazon.com/gp/product/B00GWFECWO/ref=oh_aui_search_detailpage?ie=UTF8&psc=1) And lightly solder the wire onto the test points I like to measure. I then hook my probes to the wrapping wire and turn on the device. This then gives me the full freedom of connecting as many DMMs (most of my DMMs have clip leads on them) as I want and as many scope probes I need.

I understand your concern.  But when the needles are very sharp, this never happens because as soon as it touches the IC's lead, it bites right into the metal and won't slip.  If you have the possiblilty to stick the needle in the softer solder, that's even better.  In worst case, if you're really worried about shorting a critical circuit, you have the option of scraping off a bit of PCB enamel to uncover the trace of interest, and use that bare copper spot to probe the signal.

But as an example, I've been debugging a baud rate problem on a super small circuit, the VESD05A8A in the LLP1713-9L package, where pins are 0.2mm wide and 0.4mm apart!  The probes did a marvelous job.  Before that, I tried the scope probes, and I got that slipping+shorting problem all the time.

[Cortex]

@cortex seems to have relisted his little probe kit for a bit less than $50 and it actually looks quite competitive compared to similar products, IMHO.

Cortex, have you ever considered using mini coax, and including a grounding connection for the metal plate? If I bought something like that I would either expect it to have a grounded shielded probe or I would modify it afterward to use shielded probe wire. I tried to build something similar using mini coax, it remains in a semi unfinished state, I need some more parts.

I was using old drafting tools as the source for my parts. They are very cheap considering what they originally sold for.

Thanks!  I think the quality/price ratio is hard to beat.  I sure would love to mass produce them because right now, the profit margin is ridiculous.

About the coax idea, I must admit that I try to stay away from specialy items like this.  The less parts the better.

The only other model I might create is an universal probe holder, so you will be able to position your fancy 500MHz+ probe precisely and directly on the PCB.  The grounding challenge is left to you as usual, because it depends on each circuit's topology (where's the nearest ground) and the wire must be as short as possible.

[AntonLoeb]

Does someone have experience with this probe holder https://youtu.be/FUY33geMrq0?

[HighVoltage]

Does someone have experience with this probe holder

Welcome to the forum, AntonLoeb.
Do you have any idea who makes it or where to get it?

[georgd]

https://www.probeholder.com/

Swiss made, costs 98 CHF.

[JohnG]

Harbor Freight is your friend (or your regional equivalent): https://www.harborfreight.com/multi-position-magnetic-base-with-fine-adjustment-63663.html

John

[tooki]

BTW, I changed my design a bit, to include another thumb screw for the coarse boom vertical offset adjustment, and traded all Torx for more popular Philips screws.

Any updated listings?

Also, pity about Torx — I think it’s the superior screw head for nearly all applications. I kinda wish Phillips would shrivel up and die. (Up in Canada you use Robertson screws a lot, right? So maybe you have fewer hateful experiences with Phillips. It doens’t help that many screws are actually PoziDriv, which works with a Phillips driver, but with even worse performance... and most people aren’t aware of PoziDriv so they don’t have the right drivers.)

[MrW0lf]

And Phillips is popular where? Masoland? For big things Torx and small things hex. For example with power tools everything adjustable is hex, and everything you screw into things is Torx. My CNC was also all hex and for stuff I added to it also did choose hex. No failures.