eevBLAB #33 - Why Gold Plated Probes Matter

[EEVblog]

That's funny - we just threw out a bunch of cheaper gold-plated probes in the trash yesterday - just about 100% crap compared to Keysight / Fluke probes for what we do.  We should have sent them to Dave for a "squiz" as he puts it. 
You'll probably never use a probe on its side as Dave was demonstrating.  The very tip is the business end, and might last a while as long as you're not trying to weld with it on high current range.  We make the young lab techs pay for the good probes when they try that....

Which is why I qualified with saying electronics use.
For high current use, yes, stick to regular probes. The same thing with relays and high current switches, you get gold plating on the low signal level ones and a silver alloy or some such on the high current ones. Basic switch engineering. Again, why people think this is different for probes is beyond me.

No one has ever complained when I have recommended gold plated probes before, nor my BM235 probes which are gold plated for example, people love them and recommend them, but this video seems to have somehow bought everyone out of the woodwork that now are now suddenly crap? 
Heck, when I started a thread discussing which probes to offer with my 121GW meter many people said the gold plated ones were better. Are people now changing their mind and suddenly don't want the BM235 probes with the electronics oriented 121GW?
What about the my BM235 and the probes everyone raves about? Should I suddenly stop selling them because they have this useless gold plating on them?

[alm]

Did you consider that this may not be the same group? I, for one, have zero intention of buying a BM235 or 121GW meter, so why would I complain about the BM235 probes? I have never handled them.

What does switch engineering say about the wiping action on gold-plated contacts? I believe gold plated contacts are generally used on contacts with little wiping action, since wiping contamination is not as necessary. But I would argue that probe tips (the very tip) see a lot of wiping/rubbing action, so corrosion is not as much an issue and contact wear is. Gold plated relays are often rated for a very low current. A too high current will vaporize the gold plating. Does not sound good for general purpose probes that might see the occasional amps.

Also you could have done better with the demonstration. Measuring current across a small value shunt resistor with various contact pressures, bonus points if the solder is somewhat crusty (e.g. an old µCurrent). Or brushing along a row of IC pins trying to find the one pin that is connected to the node you are probing. I realize this was a spin-off from the pocket DMM test, but the test did not do a good job supporting your conclusion in my opinion.

[vk6zgo]

Which is why I qualified with saying electronics use.
For high current use, yes, stick to regular probes. The same thing with relays and high current switches, you get gold plating on the low signal level ones and a silver alloy or some such on the high current ones. Basic switch engineering. Again, why people think this is different for probes is beyond me.

Electronics is "a broad church", from NASA or ESA clean rooms to groping around in the guts of an AM
Broadcast Transmitter in the middle of red dirt territory.

In the latter case,you are probably using the same probes in the smaller, cleaner part of the device that you used in the large dusty power supply, or even to check the Station batteries.

Techs & Engineers in such situations are unlikely to carry two sets of test leads.i

Of course, for your own Lab, why not try for the best result you can get?

[EEVblog]

Did you consider that this may not be the same group? I, for one, have zero intention of buying a BM235 or 121GW meter, so why would I complain about the BM235 probes? I have never handled them.

Maybe, but on statistics alone I would have expected one person to raise their hand and complain about offering gold plated leads. Yet not a single person did, nor has done so on my BM235.

What does switch engineering say about the wiping action on gold-plated contacts? I believe gold plated contacts are generally used on contacts with little wiping action, since wiping contamination is not as necessary. But I would argue that probe tips (the very tip) see a lot of wiping/rubbing action, so corrosion is not as much an issue and contact wear is. Gold plated relays are often rated for a very low current. A too high current will vaporize the gold plating. Does not sound good for general purpose probes that might see the occasional amps.

Which again is why I clarified in the video that for "electronics" use.
IME gold plated probes have never really been a problem, and in fact I find them beneficial. YMMV.

Also you could have done better with the demonstration.

Yes, I know, it was a quick single take blab video. Doesn't seen to have done down well with a small vocal section of the community. Many other however got what I was getting at.
Meh, I'll just move on.

[MisterDiodes]

If you have two oxidised surfaces you are trying to touch then you have two oxide layers you have to pierce in order to get your good contact. If you one contact that is perfect and not oxidised then you only have one oxide layer to pierce.
Basic contact engineering.

That's the problem:  Gold is so soft it's not piercing any oxide layer - it normally mechanically wears away quickly at the tip since any oxide it encounters is many times harder - in a very short time the underlying substrate metal is doing the work as the conductor contact point.   

We work with this stuff all the time at a microscopic level, and that's what's going on.  See it in action every day, especially on a wafer prober that needs to use fine gold-over-stainless tips, hundreds of tips at a time that need to touch gold pads- any oxide contamination anywhere absolutely destroys the connection.

If you do have soft gold on soft gold contact, then that is a great connection!  Otherwise not so much.

[MisterDiodes]

Dave,
Gold plating or not, I think you just found out how many people pay attention to your vids

I needed to give you a "Thanks" in there also for all your efforts and providing the forum.  Some days it's not easy....

[Wim_L]

And Fluke does, in fact, offer gold-plated probes. The TL910 has replaceable probe tips, it's delivered with a set of stainless steel ones, and multiple sets of spring-loaded gold (so that's a good indication they expect them to wear out faster than the stainless steel ones, even if the springy probe tips should suffer less from overly hard mechanical action).

[EEVblog]

Dave,
Gold plating or not, I think you just found out how many people pay attention to your vids

I also found out how many people take things personally, like I insulted and humiliated them for not using gold plated leads 

[EEVblog]

And Fluke does, in fact, offer gold-plated probes. The TL910 has replaceable probe tip

Ah, yes, forgot about those. And what do you know, they call them "electronic" leads, wow what a coincidence!

[TheSteve]

Fyi the probes with my 34461a and u1282a both trigger the continuity beeper constantly under there own weight like your gold probes do.
I like gold plated stuff, but as others have said the gold on the tips will be gone in no time.
A better version of the video would have had some new probes with and without gold compared as well as the aged ones.

[vk6zgo]

Gold used in rings, etc, is usually an alloy to get around the softness of 24ct gold.
These things survive for many years,without much wear.

Possibly, the gold plating on probes is the same.

[SL4P]

I noticed that the beeper in my Fluke sounds much more authentic and 3D when I am using gold coated probes!

Don't tell Batteroo / Batteriser (or whoever they are this month)   

[EEVblog]

A better version of the video would have had some new probes with and without gold compared as well as the aged ones.

FYI, the Agilent ones were brand new out of the packet

[MK14]

Out of curriosity.

Does the gold probes (only 1 X oxide layer from the device under test) vs non-gold probes (2 X oxide layer), cause resistance readings to be out by a certain amount (due to the small current flow making a voltage drop, between the non-gold probe tip and the lead of the device under test) ?
I suspect the answer is NO, as we are probably only talking about additional milliohms worth of resistance (going by typical switch contact resistances).

When you short the probes together, and the meter reads a small resistance, of perhaps 0.5  .

Does that reading (super very approx 0.5  ), reduce for gold plated tips ?

Analogy:
This to me, sounds a bit like comparing the switch (or relay) contact resistances (and whether wetting currents are needed or not), between different contact type plating's, such as gold to gold, silver, etc etc.

Explanation as to why the very quick probe flick/beep test, is sometimes important/needed
Sometimes you want to see if a particular signal (input or output) line, connects (or not), to a particular integrated circuit.

So with a quality (fast beeping) multimeter and probes set, you can (in beep continuity mode), put one probe on the signal line of interest, and quickly skim the other probe tip, across the various pins of the IC(s) involved.

E.g. You might NOT have the schematic available for something you are repairing.

[Electro Detective]

I always use the probes that suit the job

If Dave is referring to the "1KV 10A Cat 4" Brymen gold tip probe leads with non-gold metal shrouded plugs,
I've got a pair of those and they perform well, easily on par with the big dollar Fluke leads

I wouldn't use them at a crusty switchboard or to pierce blackened contacts on a vintage tarnish magnet,
I've got tough stainless probes for that or sharp prod n scrape tools to get the party started

Cleaning solves a lot of meter contact issues anyway, especially if playing with low ohms


FWIW, the Brymen leads work great      better than many of the bog standard flex challenged Fluke leads, 
but I will never find out how 'tip tough' the Brymen are because I use them for board surfing,
so they need to be in good 'beep beep' shape always/forever

(or till the sillycone rubber perishes or turns to goo)

[nctnico]

Yes, but you are missing the point entirely.
If you have two oxidised surfaces you are trying to touch then you have two oxide layers you have to pierce in order to get your good contact. If you one contact that is perfect and not oxidised then you only have one oxide layer to pierce.

Gold is too soft to do any piercing. It is like using a wooden toothpick to carve granite. And it is not just oxide but also flux residues. As others already mentioned: stainless steel is much better because it is hard and it doesn't oxidize.

[SeanB]

Stainless steel does oxidise, and the oxide layer on the surface is the thing that makes it stainless, as it is covered with a thin chromium oxide layer that keeps the base metal away from oxygen. Gold is typically applied to a surface after a nice smooth nickel plate is applied, so even if the gold wears away there is a pretty hard near monocystalline nickel layer as the contact, which is pretty good as a conductor still, and under that there will be a thin copper interface layer deposited before you hit the base metal, probably in most cases a brass alloy of some sort.

I have some really nice gold plated probes that came with an insulation tester, and they are some of the best leads i have, gold plated and very flexible. Wonder who the OEM of those are, as Major Tech is always a rebranded meter, but they are really good probes, and as I know very sharp.

[G0HZU]

Fyi the probes with my 34461a and u1282a both trigger the continuity beeper constantly under there own weight like your gold probes do.
I like gold plated stuff, but as others have said the gold on the tips will be gone in no time.
A better version of the video would have had some new probes with and without gold compared as well as the aged ones.

I agree but the tests in the video were poorly controlled and unrealistic anyway. It would be interesting to see if it would be possible to wear away the gold from the sharp tip of those cheapo looking Probemaster probes inside a few days. i.e. inspect under a microscope on day 1 and then do a few hours' continuity testing on a wiring loom or complex PCB. Repeat over a few days. Then inspect the very tip of the probe under a microscope again. Even when the gold plating is gone at the very tip the probe tip will probably still look intact to the naked eye 

Any keen user of a DMM will eventually wear out the plating on the tips of a set of regular DMM leads, but nowhere near as quickly as on those gold plated probes in the video

[R005T3r]

Beside the fact that gold is not a highly reactive material, this video made me think about an interesting thing: beside the oxide, if you polish two sufraces and rectify them, the contact resistence should be a lot better, even better than the gold plated ones...

As stated above, it might well be the surface might get rought whit oxidation...

[SNGLinks]

(1)I was "brought up "on analog meters which don't "beep".

Do they not have audio feedback from the needle hitting the end stops?

Only if you miss-adjust the zero ohms pot.

[thm_w]

Fyi the probes with my 34461a and u1282a both trigger the continuity beeper constantly under there own weight like your gold probes do.
I like gold plated stuff, but as others have said the gold on the tips will be gone in no time.
A better version of the video would have had some new probes with and without gold compared as well as the aged ones.

I tried with a Fluke 115 and ~2 year old Pomona leads, stated as nickel plated brass (http://www.pomonaelectronics.com/pdf/d6601_2.pdf). They are a bit shinier than the ones Dave used.
Couldn't reproduce the probe sitting on the other and not triggering, tried for 5mins.
In the video you can see the resistance sits in the 500k(?) range, I can't get this to happen on continuity. But if i switch to resistance mode, hovering one probe carefully can get a reading of ~20k or so.

So I wonder if continuity mode on the 121GW is partially to blame here. Not saying its bad, just that whatever Fluke is doing for continuity is more sensitive to trigger.
The Fluke 115 outputs 2.5V in continuity mode. How does that compare to 121GW?

[Old Don]

When I was looking for new leads for a nearly 40 year old Fluke 77, that I purchased new way back when, and I didn't like the new Fluke leads I saw. I have several sets of crap leads I picked up over the years and decided that I'd pick up something better than more Chinese knock offs. So I purchased a set of the Probe Master leads and the gold plating was only one reason. I like the shape of the probe, I like the screw on adapters, I like the fact that they're made in the USA vs. China and I really like the price. While I'm sure there's better leads on the market, at some point I wonder if the cost vs. performance is justified. 

If you don't want gold, then so be it, don't buy them. People want to pick on anything they don't like these days! Is there any downside to having gold plating? Gold vs. whatever doesn't seem to be too important to me, but I don't see how having gold plating can cause any problems even if they do/don't add to the performance. For all I care, they could be coated with yttrium (I think that was the coating) used on the old Xcelite screwdrivers. Xcelite once upon a time were made in my old home town and easy to come by. OBTW, the Xcelite coatings used to flake off and yet the screwdrivers worked just fine. If nothing else, the gold looks good while probing fried Chinese made PCB's.   

[schopi68]

In the video there is one test missing:

not probe against same probe - but probe against another material (i.e. all probes against solder joint or against the same nickel-platet one or so). If the gold plated probes are beforming better in such a test, then gold is the winner.

[JDW]

I found this 121GW review which shows that it once came with gold-plated probe tips and even included a banana connector tip too.  I purchased my 121GW new in Jan. 2023, but the tips are not gold and there is no banana tip, although there is the plastic shroud. 

When did the 121GW's probes change, and why?

(BTW, the soft case shown in the aforementioned review is also no longer included.)

3/25/2023 UPDATE:  I got the answer to my question by querying Dave on the matter in another thread, which I show at the 26:08 time stamp in my 121GW Review video.

Separately from that, I also made a video review of the Probe Master 8043SK kit, which includes the fabulous gold-plated probes...



I disagree with a lot of the naysayers who poo-poo the idea of gold-plated probes because I am not constantly sparking 10A of current across the probe tips.  But for anyone who is wonder what happens when you load Probe Master probes with significantly greater than 10A of current, check out this Tested to Failure video here.