They're standing by their suppliers and I have no reason to doubt them given their feedback on these probes. I think the issue is with my faulty methodology more than anything else.
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I can take some images of mine, but there may be some revision changes over the years. I've had mine for many years. I've got four 10073C and I've probably still got a couple of 10073A probes (1Meg version) There probably are fakes out there and (if so) some of the fakes will probably work quite well.
The other signature tests you can do include measuring the S11 response to 500MHz looking back up the BNC connector. Then compare the results with mine.
Try your sig gen test again but you need to do it with a proper 50R termination and ideally do it with an attenuator at the sig gen output to better define the source impedance of the sig gen up at UHF. 10dB or 15dB would be good values.
Or you could politely ask the ebay seller for help. Maybe they can tell you where the probes were sourced from or they could put you in touch with other purchasers of their probes to see if they are happy.
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Re: Fume extractor recommendation
In message < [email protected]>, Matt Harris <kd4pbs@...> writes
When I was a 7 year old kid, up until I was 18, I fished frequently
during the summer.? I always used lead sinkers.? I also always
Snipped a tad!..
I think people in California have much greater hazards to worry
about than fumes from soldering.? And if it doesn't matter to you
that things of this nature exist mostly to make people rich, go
ahead and purchase the most expensive new fume hood setup you can
find.? One that gives tons of CFM, purifies the exhaust with
hyper-expensive filters which cause far greater environmental
damage to manufacture and dispose of than it could ever avert.? ?If
you so strongly believe this to be a problem, why would you settle
for anything less?? To do anything less would be killing your
family.? To do anything less would be hypocritical and bad for the
state.? If you know in your heart that there is grave danger in
soldering things, your choice is clear; extremely expensive
filtration which is guaranteed to eliminate 100% of the
contaminates, or ceasing to do that kind of work.? Also, be sure
you register your home as a potentially disastrous environmental
pollution source; I'm sure the CA ministry of environmental
protection directorate would want to know.
I think Matt you left out Beryllium Oxide dust from RF devices in that lot;)...
-- Tony Sayer Man is least himself when he talks in his own person. Give him a keyboard, and he will reveal himself.
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Re: Fume extractor recommendation
Believe me-? it is totally possible to light cigarettes from
soldering guns and irons!? I had to endure the resulting?? toxic
stench for too many years.
?? Bruce Gentry, KA2IVY
On 4/11/24 13:16, Jim Adney wrote:
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? As others have stated, the most common risk occurs via
swallowing, although lighting your cigarette from your soldering
iron (Does that even work?) sounds foolish.
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Re: Agilent E4406A Pulling down the power supply not starting
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Jmr,
I've got no idea what to make of this thread, to be honest. I lost the plot about half the posts ago so I've no clue which of the ideas presented has the most merit. I'd probably be better off examining a known genuine probe side by side with the Ebay one under a 30X stereoscope and a bright light and ignoring any electrical performance altogether. I'm perfectly certain a fake probe would not stand up to such scrutiny at that kind of magnification.
J.
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Re: Agilent E4406A Pulling down the power supply not starting
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Thanks. I think this means the resistance of the series (divider) resistor in the tip must be about 2 Meg ohm. I still think the best test of the probe will be to test the integrity of the waveform it produces when probing a fast pulse from a decent pulse generator. There are pulse gens that can produce the required test pulse.
Otherwise, it's a case of making something. I have several homebrew pulse circuits here, each with differing rise-time. The aim isn't really to just quantify the rise-time, it's also important to look at how nice and square the waveform looks on the scope. Some cheaper x10 probes will probably give a similar rise-time, but they won't be able to produce a tidy pulse shape. I'd expect to see more obvious artefacts with the cheaper probes. This might mean much more overshoot and ringing and some other artefacts caused by inconsistent compensation across LF through UHF.
The risk with using a sig gen to try and simply measure the bandwidth is that it doesn't really prove if the probe is genuine or not. By all means try Robert's BNC Tee method but I think it will make the 10073C look flatter than it really is when compared to the passive 3.5GHz probe. If that means it makes you happy then go for it. In my opinion, Robert's method would get thrown out if it was sent for a formal design review where I work, but maybe it's OK for hobby use. I've tried to explain why it isn't as good as he thinks, but I'm not sure I've succeeded.
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Re: Agilent E4406A Pulling down the power supply not starting
Hi I'm doing as it says in the manual.  I don't have the tensions. And every time there is a pulse it resets the voltages. Both + and -.  The processor LEDs always blink. 
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Re: Agilent E4406A Pulling down the power supply not starting
I will tell you the tests I did.
I turned off all the accessories.
I did a good cleaning.
I only left the motherboard with the fan controller.
I replaced all the 100k 1206 and 150k 1206 resistors. Same problem. I measured the old resistors and checked that they were good, and put them back in.
The source LED turns on (green), but I hear a noise when it pulses.
The red LEDs on the fan control board sometimes light up (red) and sometimes not.
Same problem continues.
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Thanks for that. I'm all in favour of simple tests!
I assume you mean the button marked 'REF' as there's nothing else orange on that probe.
With the button out I'm seeing 287k and button-in 388R. So essentially the same as yours, allowing for the fact that this meter is not really intended for measuring ohms precisely and only has a few digits of accuracy. I have other more accurate meters if necessary.
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Re: Fume extractor recommendation
Perhaps something on the order of a fan/filter used for hobby woodburning or gourd burning would work for you.? You'd likely want a 3D printed adaptor to go to a hose.? One from a CPAP unit might work well, or you can make something with 3D printing and use a small fan.? You don't need much air flow, but I'd recommend a carbon filter.
Harvey
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On 4/11/2024 1:58 PM, Steve Hendrix wrote: On 2024-04-11 01:51 PM, Howard Hoyt wrote:
2) Using a microscope for SMD work I noticed the flux condensing on the final objective and causing blur.? Fume extraction fixed this problem as well. DING DING DING DING!!! You just explained something I've been seeing, and never even thought about. Now I need to think about how to get just enough air movement to keep the flux fumes away from the lens (and the operator), without unacceptably cooling what I'm trying to solder.
Steve Hendrix
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Re: Fume extractor recommendation
On 2024-04-11 01:51 PM, Howard Hoyt wrote: 2) Using a microscope for SMD work I noticed the flux condensing on the final objective and causing blur.? Fume extraction fixed this problem as well. DING DING DING DING!!! You just explained something I've been seeing, and never even thought about. Now I need to think about how to get just enough air movement to keep the flux fumes away from the lens (and the operator), without unacceptably cooling what I'm trying to solder. Steve Hendrix
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Re: Fume extractor recommendation
>>Fume hoods used in soldering typically
>>are just to reduce irritation from flux smoke.
I concur and having worked in high vacuum systems (optical disc manufacturing) I knew the vapor pressure of lead is quite low, as both it and indum have historically been used for sealing washers in chambers.? I personally have two reasons for a fume extractor...or re-mover:
1) After having a bench soldering job for 2 years I had my blood lead level checked...and there was none, but that flux gave me a sore throat and the idea of the resin vapor condensing in my lungs was not a comfortable one.? Although NIOSH does not have any specifications or specific guidance about lead solder other than avoid the vapor, it does warn against flux inhalation.? The tree sap (called colophony) rosin flux is made from is 90% rosin acid and in addition to it's beneficial oxide scavenging it is also irritating, especially to mucous membranes.
2) Using a microscope for SMD work I noticed the flux condensing on the final objective and causing blur.? Fume extraction fixed this problem as well.
Cheers,
Howard Hoyt
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Re: Fume extractor recommendation
On Wed, Apr 10, 2024 at 11:42 PM, Chuck Harris wrote:
Fume hoods used in soldering typically are just to reduce irritation from flux smoke.
I think this is probably the most important point made in this discussion so far. Here's why: In a previous life, I worked in an industry where high vacuum was a critical part of the process. In our work, vacuums of 10^-5 Torr were considered poor, 10^-6 were okay, and 10^-7 were good. My test bench typically sat at 10^-8 and would sometimes get into the 10^-9 Torr. [FYI: 1 std atmosphere is 760 Torr.] There were certain elements, with high vapor pressure, that needed to be kept completely out of the vacuum systems, since they would "poison" the chamber permanently. The main such elements were Zinc and Cadmium. Because Zinc is a major component of brass, brass was not allowed. Of course, things like Mercury would never be allowed, but Hg is not something that might ever come up. Zinc and Cadmium plated hardware were common in those days, so that kind of hardware was not stocked in our stock room. It is common to think that anything with a low melting point might be a high vapor pressure problem, but it turns out that vapor pressure does not follow the melting point, it follows the boiling point. It turns out that lead has quite a high boiling point, 2022 K = 3180 F. The correlation between boiling point and vapor pressure make sense once you understand that boiling occurs when the vapor pressure reaches atmospheric pressure. I turned to my copy of "Fundamentals of Vacuum Science and Technology" by Lewin, to look up the vapor pressure curves of Hg, Zn, Cd,? Sn, and Pb. These curves were developed by RCA in the early 1960s, presumably to determine suitability for use in vacuum tubes. Here are those vapor pressures at 300 K (room temp) and 600 K (the melting point of Pb.)? Hg: 10^-3 Torr, 10^+3 Torr Zn:? ~10^-13 Torr, ~10^-2 Torr Cd:? ~10^-11 Torr, ~10^-1 Torr Pb:? 10^-11 Torr,? <10^-8 Torr Sn: off the bottom end of the scale (10^-11 Torr) at all temps below 800 K If you look at these numbers, you will see that the vapor pressure of Pb at 600 K (which is higher than the melting point of eutectic Sn/Pb solder) is 100,000 times lower than the vapor pressure of Hg at room temp. And I learned that Tin/Lead solder is an acceptable vacuum material, EXCEPT for the fact that it often had trace quantities of Bismuth in it, which made it unacceptable, because Bismuth has unacceptably high vapor pressure, and it's melting point is low enough that it may melt in a good system bakeout. Consequently, I don't believe Sn/Pb soldering, with a controlled temperature iron, not a flame, is a health hazard to you or your family. It's probably prudent to vent large molten baths of solder as used in PCB production soldering, but that's not what you're doing.? As others have stated, the most common risk occurs via swallowing, although lighting your cigarette from your soldering iron (Does that even work?) sounds foolish.
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I thought of another couple of simple 'signature' tests you can do with the 10073C probe if you have access to an ohmmeter.
Measure the resistance across the BNC connector at the scope end of the probe. Don't connect the probe to anything else other than the ohmmeter.
Two of my probes show 287.7 k ohm in this test.
Then, keep measuring the resistance and then press the little orange ground button on the probe. This tiny button is on the tip section.
With this button pressed you are now probably measuring the series loss resistance through the coax cable. My two probes show 376 ohms and 378 ohms in this second test.
This isn't a definitive test, but hopefully you will see similar resistances with your ebay probe?
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Re: Fume extractor recommendation
For dirt cheap, a 5" muffin fan from any cast-off PC,
the base part of a dryer vent wall piece and a length
of dryer hose and a 12V wall wart, you're done.
On Wednesday, April 10, 2024 at 08:30:11 PM EDT, Radu Bogdan Dicher <vondicher@...> wrote:
Hi all,
I've had a recent scare with potentially evil metals that can vaporize - you know who you are.... - and absolutely need a good, and hopefully affordable, solution for my bench soldering needs. And hopefully, not just something I'll put on there for peace of mind but have no idea if it really does anything. I really want this to work.?
Are there any such things this community can recommend? I don't think I can go used on this kind of thing, not knowing what Martian "deadly on sight" materials the thing may have exhausted in its life. Nor I really feel I can trust the vanilla low balling specimens on AMZ. Being a health-related thing, I feel it kind of needs a trustworthy solution, but my budget for this is limited.
Thank you for your input!
Radu.?
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Locked
Re: Lothar Baier - please explain the possible 8703A -> 8720B deception
I am locking this topic as I inadequately posted it to the wrong group.?
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On Thu, Apr 11, 2024 at 02:31 PM, Steve Hendrix wrote:
I've been following this discussion with interest, no particular expertise to contribute. Is your statement above based on the leads and other parasitics adding some inductance, which starts to cancel the capacitance at higher frequencies?
I think only a small part of the input capacitance is going to be fairly consistent with frequency. This will be the shunt capacitance to the ground ring right at the tip where the tip will be a bit like a really short coaxial section ahead of the divider resistance. Much of the rest of the capacitance will be the series compensation cap (across the divider resistance in the tip) and this is then in series with a run of lossy coax. Up at UHF the loss will tend to make the net (parallel) capacitance Cp go down slightly with increasing frequency because the coax section will look like a loss resistance in series with the tip capacitance. In other words, the parallel equivalent of (say) 10pF in series with a 50R loss resistance will gradually go down with increasing frequency. Ideally, there should be no reflections in the coax section of the probe and this is usually achieved by making the coax really lossy and this makes it look more like a resistance. This can probably explain the way the capacitance changes up to 100MHz or so, but above this it will be much harder to understand without taking the probe apart.
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Re: Fume extractor recommendation
One wonders how the extraction (death) of military people, WWI 20,000,000 approx,? approx 60,000,000 WWII who had the "best" health and genes has affected the prevalence?of various diseases like cancer.
I have never come across a scientific?study on the extraction of over 80,000,000 people/genes delving?into the results we see today.
On Thu, Apr 11, 2024 at 8:21?AM Peter Gottlieb < hpnpilot@...> wrote: Getting OT but I will note that things like cancer are probability based and
include genetic disposition.? Raising the risk of cancer from 0.001 per thousand
to 0.01 per thousand still means you are extremely unlikely to get it, yet 10
times more people will and in addition to it being terrible for them we all pay
the costs through higher health insurance premiums.
You are free to make your own choices but others will want to take a more
cautious route.
Peter
On 4/11/2024 10:38 AM, Matt Harris wrote:
>
> When I was a 7 year old kid, up until I was 18, I fished frequently during the
> summer.? I always used lead sinkers.? I also always crimped them on the
> fishing line with my teeth.? I also remember chewing on one of the sinkers on
> more than one occasion just because it was fun.
>
> I have also have amalgam fillings in a few of my teeth.
>
> I have also handled mercury from a broken old thermometer with my bare hands -
> because it is fun - and Mercurichrome was standard faire in our home when I
> was growing up; both the dab-on kind and the kind which came from a spray
> can.? I appreciate that Dad knew there was no antiseptic match to the product
> when applied to the newest scrape or cut which was obtained from being
> adventuresome children growing up in an amazing world without doomsayers
> around every corner warning us about the dangers of radiation from the
> Motorola color TV on which we watched Saturday morning cartoons or some other
> such nonsense.
>
> This was also the time in my life when I became interested in electronics.? I
> loved the smell of the pine-based (or whatever it was made from) rosin in the
> 60/40 solders of that era.? I created many projects and desoldered many old
> boards for spare parts.? And I stripped tinned wires with my teeth.? In fact,
> I still sometimes hold the solder with my lips when I need a third hand while
> soldering things.
>
> My last home had copper pipes with lead solder solidly holding it all
> together.? I raised two children in that home.? One is a brilliant biotech
> engineer who graduated in the top 1% of her class.? The other has an IQ as
> high as his old man had 30 years earlier.? They grew up in that same home
> where I soldered things on probably a weekly basis - and I never use lead free
> solder.
>
> When I was a teenager, I worked in an auto shop which performed brake jobs and
> had a machine to grind new brake shoes to the proper size.? Those shoes and
> the dust they created contained asbestos.? Later on, I worked for a shop which
> installed and maintained industrial sound equipment.? Often times we were
> tasked with drilling holes in asbestos materials to run new audio wiring.?
> Then I worked at a radio station which had a transmitter that held within it
> PCB containing capacitors and transformers in an old building with asbestos
> ceiling tiles. Later, I went to work for a TV station which had huge Klystron
> beam supply transformers which also contained the rectifier stack, all cooled
> with PCB-containing transformer oil.? I've often been up to my shoulders in
> that oil while reaching in to unhook and retrieve the rectifier module to
> replace the blown diodes... the worst part of which was the fact that there
> was always a stored charge on those components simply due to being in close
> vicinity to 36KV in that oil, even though every possible point which was
> reachable was already grounded out with the "chicken stick".? It was always an
> adventure to reach into that oil.
>
> One would think nowadays I'd be a walking bag of cancer or a blathering fool
> given the paranoia surrounding [insert purportedly dangerous substance here]
> in our environment to which I have been exposed my entire life.? And while
> that can be debated by some, I'd instead let the IQ test I took in my
> adulthood and my current state of close-to-retirement-age old-fartdom speak
> for itself. I think the biggest hazard I have to worry about right now is all
> the Marlboros, Big Macs and Coca-Colas I have consumed over my lifetime.
> /Those/?are indeed the scourge of this country, and I'm happy to say I
> more-or-less swore off them all almost 20 years ago - but I would never dream
> of limiting someone else's freedom to partake in those same things if they so
> choose.
>
> I will admit, however, that I wasn't very smart in choosing to marry a very
> liberal thinking person who believed in most of these hoaxes perpetrated by
> those who have huge financial interests which would be greatly increased by
> the populous believing their stories.? Thankfully that mistake is far behind
> me and I learned a great deal from it.
>
> I think people in California have much greater hazards to worry about than
> fumes from soldering.? And if it doesn't matter to you that things of this
> nature exist mostly to make people rich, go ahead and purchase the most
> expensive new fume hood setup you can find.? One that gives tons of CFM,
> purifies the exhaust with hyper-expensive filters which cause far greater
> environmental damage to manufacture and dispose of than it could ever avert.
> ?If you so strongly believe this to be a problem, why would you settle for
> anything less?? To do anything less would be killing your family.? To do
> anything less would be hypocritical and bad for the state.? If you know in
> your heart that there is grave danger in soldering things, your choice is
> clear; extremely expensive filtration which is guaranteed to eliminate 100% of
> the contaminates, or ceasing to do that kind of work.? Also, be sure you
> register your home as a potentially disastrous environmental pollution source;
> I'm sure the CA ministry of environmental protection directorate would want to
> know.
>
>
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Jinxie
Dr. David Kirkby, Kirkby Microwave Ltd