Some time ago jw0752 made contact with me and wanted to send me some of his meter probes.
He's been keeping the community up to date as he makes changes to the original concept.
Shop Tips - Intrusive Meter Probe
For anyone that hasn't followed John's work, his background is in dentistry equipment repair, and this has been the source of his inspiration for this product.
As the blogs testify, John is very practical and has applied this to solving many of the problems faced in his life.
Good connection
Anyone that uses multimeters regularily will tell you that getting a good connection to the device under test is essential.
More importantly a poor connection can steer you along the wrong repair path, which can cost money and time.
One day john was faced with just this problem and his solution was to use a dental burr bit on the end of the lead.
This would break through the coating and allow a good connection.
Special meter probes are available from manufacturers. I haven't priced them but the one annoying thing is you need to change the lead.
I have a couple of Keysight meters, and they get around this by having interchangable ends on the leads.
I haven't looked to see if Keysight do make a special sharp probe point, but I have seen others.
They are popular in automotive uses where they can pierce the insulation of the wires, but obviously they are dangerous due to the sharp nature required.
Johns solution won't pierce wire insulation, but overcomes the safety aspect by providing a flat end with multiple sharp parts that can bite through the thin coatings found on most circuit boards, .
As you can imagine they are not some cheap piece of metal with a token gesture of hardening, they are designed for digging holes into teeth, so the copper and aluminum we encounter is like butter in comparison.
In typical fashion John's latest iteration is designed these to simply slip over the end of the existing meter lead ends which means they are a universal fit.
Good meter leads are designed to protect the user from dangerous voltages. They include a wider section to stop fingers slipping down and making contact with the metal end.
The nature of this design makes them difficult to use one handed, and I can only imagine what happens when hand dexterity becomes an issue.
To give you an example of how useful these are, I tried measuring a resistor while it was sitting on the bench.
Modern probes have a reduced diameter near the end, and you can try angling the probe to utilise this to make contact, but if you tried this while it was in circuit, it wouldn't work.
Johns probes simply slip onto the end of the probes, and the task is not only possible, but the pressure required is significantly reduced as well.
It becomes so easy that it can be done one handed without much effort at all.
This shows you why.
Probe Slipping
Slipping is a cause of many electrical accidents. You're trying to balance a meter, put one meter probe onto one connection and then stick the other meter probe onto another point in the electrical switchboard.
In many cases there is a slip somewhere and with careful thought it won't be you making contact with a dangerous voltage.
Sometimes you get away from a shock, but your hand makes contact with the metal edge or some other surface, and you have an injury, bruise or other physical injury, and to top it off you drop the meter.
The non slip benefits of these can be considered a safety device, but if you're also dropping meters, then it can be a cost saving as well.
My next tests involve 'lending' them to some of the other teams at work, and seeing what they think.
They are already trying to borrow my Keysight Insulation Resistance Tester, and I'm happy to lend it out, but it comes attached to me so I get it back. 
Keysight U1461A Insulation Resistance Tester - Review
Conclusions
So by now you will have guessed that I'm sold on these special probes.\
These are a prototype using off the shelf components, and assembled into a working product.
There are limitations on the abuse they can take from sideways pressure, but once they become a manufactured item, this will not be a factor.
I hope the ability to change ends can be incorporated, but the costing may be that this is not required.
Whatever the final product, I'm sure that meter manufacturers will be scrambling to offer it in their range, and it would be nice to think they reward John for using his concept.
Just remember you saw it here first at element14 community.
Thanks for thinking of me John.
Mark
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