Yes in a lot of cases... such as 3455A and 3456A meters. But more often than not it falls under the "wanted" category as opposed to the "needed" one. Of course, my own case of volt nuttery played a big part - this is a hobby for me and, while I try to at least break even in the long run (at least enough to placate the SO), financial gain is not my goal - it's enjoyment. And I always like a new tool toy to play with 🙄
My Eico 222 usually came up with the correct answer. I got it in high school and still use it for HV.
The difference between precision and accuracy got drilled into us both undergrad (chem and physics) and grad school! Grad school wasn't science but a lot of stat and biz.
Nonetheless, I was doing an experiment for an advanced quantitative organic chem course and had these beautiful results. The grad lab assistant saw my work as I plotted it out, took his pencil and put in a lot of random marks about the curve. He said something to the effect that the prof would never believe the results if they were so close to perfect.
I love reading the history of science and engineering. It's amazing that with the relatively crude tools of the medieval period the architects of the great gothic cathedrals figured the exact amount of balance on the flying buttresses to counter the winds in northern France...for hundreds of years folks thought that the attachments were "ornamental". (Oh, they occasionally f'd up == vide Beauvais which collapsed in a wind storm!)
Nonetheless, I was doing an experiment for an advanced quantitative organic chem course and had these beautiful results. The grad lab assistant saw my work as I plotted it out, took his pencil and put in a lot of random marks about the curve. He said something to the effect that the prof would never believe the results if they were so close to perfect.
I love reading the history of science and engineering. It's amazing that with the relatively crude tools of the medieval period the architects of the great gothic cathedrals figured the exact amount of balance on the flying buttresses to counter the winds in northern France...for hundreds of years folks thought that the attachments were "ornamental". (Oh, they occasionally f'd up == vide Beauvais which collapsed in a wind storm!)
Flying buttresses allow for vaulted stone roofs too, any arch pushes outwards as well as down. I think a lot of the figuring out back then was from models and trial-and-error, not so much calculation - and given the time taken to construct some cathedrals the goals changed during construction! Robert Hooke I believe first explained how to make an arch properly stable.
Any opinions on the Fluke 8808A? Looks decent, but doesn't appear to be all that widely spread in the wild.
My recenty acquired 8050a True RMS bench meter is accurate enough considering it dates from 1979. (0.5% 45-10kHz, 1% 10k - 20k, 5% to 50k)
The old school lquid crystal display is a bit fuzzy compared to more modern designs and is not backlit.
The old school lquid crystal display is a bit fuzzy compared to more modern designs and is not backlit.
The schematic for the display is given on page 7-4 of the manual. You could outboard the digits quite easily. Schematics are available at https://bama.edebris.com
Probably because you can get Siglents equivalent for 1/2 the cost: https://www.amazon.com/dp/B00QT3RTV...4751-16-&linkCode=osi&tag=comparaboo1-20&th=1 And you can probably get a 6 1/2 digit meter for around $1K. They are hardly necessarily needed for any audio task and not even for audio measurement instruments.
Yes the schematic is on page 104 and uses 4054 BCD to 7 segment decoders so it would be possible rework it.
Sure, but I somehow doubt that Siglent and Rigol can hold a candle to HP/Agilent and Fluke. They don't cost twice as much for nothing, do they? And I do prefer a VFD over a LCD here.
Maybe not BUT Rigol makes the lower end HP/Keysight scopes and Siglent supplies LeCroy. And how do you compare those instruments in a meaningful way? Accuracy? Stability over time? Reparability? Factory support? I have had better support for the Siglent 1104-XE than for the insanely expensive Tek DSA 8200. Tek just wants me to buy a new version. Browse around EEVblog forums to get a broader perspective.
Also Fluke and HP/Agilent/Keysight's biggest competitor is their second hand markets. I have 3 6 1/2 digit DVM's all quite old-A Prema 6002, a Keithley 2015 and a Fluke 8506 (actually 7 1/2 digits on DC). The pretty graphs on the new instruments are nice but the accuracy is no better and they would lack proven stability.
Also Fluke and HP/Agilent/Keysight's biggest competitor is their second hand markets. I have 3 6 1/2 digit DVM's all quite old-A Prema 6002, a Keithley 2015 and a Fluke 8506 (actually 7 1/2 digits on DC). The pretty graphs on the new instruments are nice but the accuracy is no better and they would lack proven stability.
That doesn't have to be a positive. Might as well mean that you get what you pay for, even when buying from the big brand name.
Build quality, maybe? If they actually all deliver what their spec sheets say, there'd be nothing to worry about. But who knows? I won't go down that rabbit hole.
It surely is. What was the price of a 34401A back then? Probably a little more than a Rigol. And they're still sought after. Somehow I don't think that today's Rigol meters will be all that popular in 30 years. This is just a guess, but I am under the impression that all these fancy LCD meters are built around an embedded PC running some kind of Linux. The firmware will be locked up pretty much, and if that PC part craps out, your meter will become a doorstop.
Should I actually decide on buying a meter for 1000 bucks, it will be the most accurate piece of kit in my workshop. To make sure it actually is, I'd preferably get a new and calibrated one right from the start. A used 34401A is certainly nice, but at the moment I'd have no means to check whether it's actually up to snuff.
All such manufacturers are true to their spec sheets (specs is a legal binding).
What drives down prices is progress in technology (integration).
Speaking of which, a 100MHz 4ch oscilloscope can be had for 400 USD.
Today with a 12 bit vertical resolution.
This increase in V resolution turns the accompanying functions of a DSO into useful instruments (not just imitations of an instrument)
George
What drives down prices is progress in technology (integration).
Speaking of which, a 100MHz 4ch oscilloscope can be had for 400 USD.
Today with a 12 bit vertical resolution.
This increase in V resolution turns the accompanying functions of a DSO into useful instruments (not just imitations of an instrument)
George
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Well, some may try to be truthful ... others may intentionally mislead... some specs drift over time more than others... some ...
Given the market audience for this type of equipment, it's unlikely that a company wouldn't suffer loss of market share and/or lawsuits if their equipment didn't meet advertised specifications. However, pretending that ALL gear from ALL manufacturers is true to the spec sheets is just folly.
Just look at audio gear... do you actually think all audio gear sold in Greece meets advertised specifications? It surely doesn't in the USA. I'm also not sure about the consumer protection laws in Greece and penalties if product does not meet specifications, but they're not wonderful in the USA. Plus... for equipment of this (advertised) precision and accuracy, you're pretty much at the mercy of the manufacturer to verify its performance. Sending a piece of gear out for a proper check to a company willing (or able) would likely cost more than the cost of the unit itself.
As always... trust in a brand is earned, but Caveat Emptor.
And... competition... and... and... and...
Thank you for responding.
Spec drift over time is of great importance. So much so that on expensive (*) equipment, drift is also into specification sheet.
(*) Well, if you watch David's video below, you'll excuse me for using this term.
IME, focus on Reasons#3,4,8 (in that order)
🙂
George
Spec drift over time is of great importance. So much so that on expensive (*) equipment, drift is also into specification sheet.
(*) Well, if you watch David's video below, you'll excuse me for using this term.
IME, focus on Reasons#3,4,8 (in that order)
🙂
George
^ Of course. Thank you also.
I am just now learning about testing gear (in this field). I have learned so much from David. He seems to be a trusted source for information among many of the other 'YouTubers'.
My experience with testing equipment is from another field altogether. I don't want to take this thread (further) off topic, but at an 'industry use' level there were manufacturers that entered the market for testing equipment I relied upon. They wanted to compete with some well-known and established companies. As a person that was lucky to have a very nice R&D budget, I still would not go for the 'new guys on the block'. I had no way to verify their claims. Yes, they could show that they had met this standard or that... but in fairness, when my professional reputation and our product's quality relied upon testing equipment; I had to go with "trusted" brands from companies that had a track record of standing behind their products.
Anecdotally - others that had saved significant (early) money buy buying from the newer manufacturers, had reported downtime and issues with service and calibrations. In fairness, I am sure that there were remarkable success stories also. Sadly, we tend to hear more about the bad than the good.
Maybe it's me just cringing at the thoughts of friends with very, very expensive test gear sitting idle while their product was waiting for validation. These were companies that couldn't necessarily afford redundancy in test gear.
We all make our own risk decisions... I am admittedly risk averse in this area.
I am just now learning about testing gear (in this field). I have learned so much from David. He seems to be a trusted source for information among many of the other 'YouTubers'.
My experience with testing equipment is from another field altogether. I don't want to take this thread (further) off topic, but at an 'industry use' level there were manufacturers that entered the market for testing equipment I relied upon. They wanted to compete with some well-known and established companies. As a person that was lucky to have a very nice R&D budget, I still would not go for the 'new guys on the block'. I had no way to verify their claims. Yes, they could show that they had met this standard or that... but in fairness, when my professional reputation and our product's quality relied upon testing equipment; I had to go with "trusted" brands from companies that had a track record of standing behind their products.
Anecdotally - others that had saved significant (early) money buy buying from the newer manufacturers, had reported downtime and issues with service and calibrations. In fairness, I am sure that there were remarkable success stories also. Sadly, we tend to hear more about the bad than the good.
Maybe it's me just cringing at the thoughts of friends with very, very expensive test gear sitting idle while their product was waiting for validation. These were companies that couldn't necessarily afford redundancy in test gear.
We all make our own risk decisions... I am admittedly risk averse in this area.
IMO, it is very on topic.
My experience was from a regulated industry sector, where everything had to be traceable, provable, documented. There, the file of an instrument's calibration history worths more than the instrument itself (and the lack of such a file may render the instrument non useable). The cost of proving that an instrument is "technicaly equivalent" to a model specified in an approved procedure can be (is) huge.
An amateur, has none of such restrictions, therefore he is allowed (or even adviced) to chose whatever suits his budget related to his technical needs and offerings from instruments tech specs.
George
Patrick, you are right.
For us amateurs, I think that having an affordable 'calibrator' at home is a realisable (200USD) dream.
https://dmmcheckplus.com/technical-information
George