Handheld meter robustness testing

[HKJ]

Not even half the rated frequency, which is what I am finding as well.   As I continued to increase the frequency, the meter will display more than 2X the actual.   Everything I tried ended with the same results.

The last meter I looked at was a UNI-T which advertised their counter over 200MHz.  I wouldn't expect Keysight to be on par with the UNI-T brand but here we are.     

HP > Agilent > Keysight > UNI-sigh

Hence my use of the derogatory "Keyshite". I am, sad to say, not surprised in the least.

Yeah, really bad meter, specifications says 20MHz and it can show up to 36MHz.

The meter is inside specifications. The way the specifications are stated makes it very easy to assume the meter can do more than specified and it can, but not as much as it looks like.

[joeqsmith]

I have no problem with the meter not being able to read up this high but the fact their marketing group would use such a tactic is a big disappointment.   

Back when I opened up the poll,  I considered adding a Siglent Arb to the mix.  We had bought one of their low end models to try out where I work.   The encoder on it is really bad.   I was going to offer to get one of their higher end models but  I'm glad now I didn't as everytime I use my equipment at home and rotate a working encoder, I am reminded how bad that Siglent is.   Would it have really cost them that much more to at least make the encoder work?   Along the same lines,  with Keysight Go Green, they could have save some ink not adding that 99.999 MHz to the document.   

[NoMoreMagicSmoke]

In this intro video, I go through a basic checkout which includes looking at the frequency function.   

Your wife's comment about the Uni-T and the annoying beeping when turning the knob definitely rang home to me. Why do they always insist on them beeping when pressing buttons or turning knobs, it's so annoying. Why can't they leave the beeping for things that matter like continuity checks, or errors??? I have a BM789 and was so excited to learn that I could turn off the beeper until I found that it also disabled it for continuity etc.  . O well, at least it's still better than my Ideal clamp meter... That dang thing lets out the loudest most annoying beep any time it senses over 40V 

[Fungus]

Your wife's comment about the Uni-T and the annoying beeping when turning the knob definitely rang home to me. Why do they always insist on them beeping when pressing buttons or turning knobs, it's so annoying.

Yep.

It could be a really short "bip", too, that might be tolerable, but noooo... it has to be "beeeeeeeeeeeeeep". Every. Single. Time.   

We're only one video in and it's already confirmed what I suspected, ie. that Keysight meters are horrible. I could buy three top-of-the-range Brymens for the price of that meter and still have change left over for a nice dinner.

[joeqsmith]

I was going to use the UNI-T 181A as part of the review today.  Attempting to turn it, the meter was dead.  The meter was purchased brand new in March 2016 and is now only 6 years old.   

Placing the meter on the charger, it appeared to attempt to charge then faulted out with the power LED rapidly flashing.     I tried it a few more times and the meter when black.   

Pulling it apart, the battery was at 0.000 volts.  Not something you can just buy at the local drug store or gas station.   Attempting to manually charge it, I was able to get the meter to boot up and so I plugged it back into the charger.   Dead.  I manually turned on the meter where I was greeted with a message requesting the charger to be plugged in.  As it turns out, they use the 400mA fuse during charging and it had blown with the battery being flat.   

 I'll let it charge overnight.  I doubt that battery has much life in it.   I wish they had used standard batteries.

[rsjsouza]

FYI, mine came without documentation.  While the contents paper states it comes with it, there is a paper that talks about them going green.  No problem.   I go to get the manuals and the first thing they want was my email address.  Google search found the direct links.   I'm fine with electronic copies but don't make me have to create an account to gain access to them.

The paper document that came with it was not very useful. Regarding the e-mail account, this is somewhat recent. Pretty stupid.

You can or can't? The frequency works alright, but there is a derating curve of sorts that is more aggressive on the V_AC Hz function when compared to the MHz range. I recall I can get several hundreds of kHz out of it. The MHz range goes to many MHz IIRC (it is specified to 10MHz)

Unless I am not understanding the document you linked, they claim 100MHz. 

Interesting; there are two tables: one named Frequency specification for U1281A / U1282A at page 14 which states 9.9999MHz and another named Frequency counter specification for U1282A at page 16 which states up to 99.999MHz with a "divide-by-100" and up to 1.8V_P spec. This last one works on the MHz range selection.

From your post:

- Frequency measurements do not require the signal to have zero crossing - good for signals with  DC offset. (common to U127x/U128x)

The meter I have appears to require the zero crossing.   You can't use it to look at digital signals for example.

Quite interesting your meter fails on this. Mine does not, in both V_AC and MHz.

[rsjsouza]

Your wife's comment about the Uni-T and the annoying beeping when turning the knob definitely rang home to me. Why do they always insist on them beeping when pressing buttons or turning knobs, it's so annoying.

Yep.

It could be a really short "bip", too, that might be tolerable, but noooo... it has to be "beeeeeeeeeeeeeep". Every. Single. Time.   

We're only one video in and it's already confirmed what I suspected, ie. that Keysight meters are horrible. I could buy three top-of-the-range Brymens for the price of that meter and still have change left over for a nice dinner.

This can be turned off via the setup menu, leaving only the button beeps (which are also annoying IMHO), the continuity buzzer and the Vsense.

[rsjsouza]

I have a BM789 and was so excited to learn that I could turn off the beeper until I found that it also disabled it for continuity etc.  . O well, at least it's still better than my Ideal clamp meter... That dang thing lets out the loudest most annoying beep any time it senses over 40V 

The U127x is also like that - enable all or disable all.

One of the best features of the Flukes 87V, 179 and 189, the Brymen BM857 and the UT-61E¹ is they are quite silent. 

¹ Not the 61; I don't know what I was thinking)

[joeqsmith]

Interesting; there are two tables: one named Frequency specification for U1281A / U1282A at page 14 which states 9.9999MHz and another named Frequency counter specification for U1282A at page 16 which states up to 99.999MHz with a "divide-by-100" and up to 1.8V_P spec. This last one works on the MHz range selection.

The manual you linked is clear about which is the Frequency Counter.    I assume that divide statement is just showing that the resolution has changed, not that the meter requires some sort of external clock divider.  If they did require such a device, they make no reference to it in the accessories or show it's use in any of the manuals that I found.     I also can't imagine anyone spec'ing their 1Hz counter to 1THz with unknown accuracy, provided to attached the 1THz divider.   Maybe the bottom of the bowl companies. 

If you can, try to see how high your meter can actually read frequency using the frequency counter function.   

[NoMoreMagicSmoke]

One of the best features of the Flukes 87V, 179 and 189, the Brymen BM857 and the UT-61E is they are quite silent. 

My BM789 is identical in beeps to my Fluke 189. Both are silent enough that I can live with them, but I still wish the buttons could be silenced independent of the wrong jack and continuity beepers.

[AVGresponding]

Not even half the rated frequency, which is what I am finding as well.   As I continued to increase the frequency, the meter will display more than 2X the actual.   Everything I tried ended with the same results.

The last meter I looked at was a UNI-T which advertised their counter over 200MHz.  I wouldn't expect Keysight to be on par with the UNI-T brand but here we are.     

HP > Agilent > Keysight > UNI-sigh

Hence my use of the derogatory "Keyshite". I am, sad to say, not surprised in the least.

Yeah, really bad meter, specifications says 20MHz and it can show up to 36MHz.

The meter is inside specifications. The way the specifications are stated makes it very easy to assume the meter can do more than specified and it can, but not as much as it looks like.

So, you don't see it as a problem that they are resorting to marketing bs/misleading statements in the manual, instead of engineering excellence, as they would have in the past?

[HKJ]

So, you don't see it as a problem that they are resorting to marketing bs/misleading statements in the manual, instead of engineering excellence, as they would have in the past?

It do not make the meter bad, it may still be "engineering excellence".

[AVGresponding]

So, you don't see it as a problem that they are resorting to marketing bs/misleading statements in the manual, instead of engineering excellence, as they would have in the past?

It do not make the meter bad, it may still be "engineering excellence".

Yes, indeed. However the attitude of the corporation to how it does business, and how it treats its customers these days is what has prompted me to rename it so. If any other premium manufacturer behaved similarly, I'd criticise them too.

Improbable specification claims from the likes of Uni-T may be taken with a pinch of salt, but when Keysight, Fluke, Rohde & Schwarz etc etc state something, I expect it to be clear, and to be true.

[bd139]

I’m confused. Which misleading statement in the manual?

There are so many compounding problems with frequency measurement on DMMs that it’s difficult to recommend them as suitable after about 200KHz or so.

Just to note I have owned a keysight handheld. One of the lower end non OLED units from the last redesign series. The user interface was absolutely dire and some of the features such as touch hold were completely useless. And disappointingly one of the buttons was sticky out of the factory. If they’d spent a couple more months on it, it’d be a good meter. I wouldn’t buy another keysight handheld b

[AVGresponding]

I’m confused. Which misleading statement in the manual?

There are so many compounding problems with frequency measurement on DMMs that it’s difficult to recommend them as suitable after about 200KHz or so.

Just to note I have owned a keysight handheld. One of the lower end non OLED units from the last redesign series. The user interface was absolutely dire and some of the features such as touch hold were completely useless. And disappointingly one of the buttons was sticky out of the factory. If they’d spent a couple more months on it, it’d be a good meter. I wouldn’t buy another keysight handheld b

This:

You can or can't? The frequency works alright, but there is a derating curve of sorts that is more aggressive on the V_AC Hz function when compared to the MHz range. I recall I can get several hundreds of kHz out of it. The MHz range goes to many MHz IIRC (it is specified to 10MHz)

Unless I am not understanding the document you linked, they claim 100MHz. 

That's snipped from the manual for the meter on the Keysight website.

[bd139]

Ah that tells me that the display range is 99MHz as they only specify it up to 20MHz. I don’t have a problem with that. If you’re getting 38Mhz out of it that’s fairly ok.

My heathkit counter is the same. It will display up to 99.999 MHz but only count to about 35Mhz.

[AVGresponding]

Earlier in the manual it only specifies it up to 9.9999 MHz... confused yet?

[bd139]

In that case their technical authors should be shot. Or at least mildly beaten with a hose.

[rsjsouza]

Interesting; there are two tables: one named Frequency specification for U1281A / U1282A at page 14 which states 9.9999MHz and another named Frequency counter specification for U1282A at page 16 which states up to 99.999MHz with a "divide-by-100" and up to 1.8V_P spec. This last one works on the MHz range selection.

The manual you linked is clear about which is the Frequency Counter.    I assume that divide statement is just showing that the resolution has changed, not that the meter requires some sort of external clock divider.  If they did require such a device, they make no reference to it in the accessories or show it's use in any of the manuals that I found.     I also can't imagine anyone spec'ing their 1Hz counter to 1THz with unknown accuracy, provided to attached the 1THz divider.   Maybe the bottom of the bowl companies. 

I wasn't sure which band you referred when mentioned the 100MHz, so I had to check and found the second table of the MHz range. My first message was clearly stating the first table that goes up to 9.9999MHz, which may correspond to the V_AC range. Regarding the divider, it was just to highlight what the table meant, not implying you were doing something wrong by not using any external device/accessory - I too can infer they mean a reduction in resolution.

Before we move forward, I need to clarify that I am no fanboy of Keysight or any other brand, just like or dislike each product of any brand on its own merits. The videos on my channel will evidence this.

If you can, try to see how high your meter can actually read frequency using the frequency counter function.

I need to find where I put my RF generator, but I got a very accurate measurement using my 30MHz generator set to 1.0V_PP on the MHz function.

[joeqsmith]

It's no problem if you don't want to run it.  I wasn't accusing anyone of being a fanboy.  This was a brand new meter and I was just curious if Keysight's older revisions may have performed better.   

[joeqsmith]

A deeper look into the Keysight's frequency counter. 

[joeqsmith]

Maybe I am the only one who found the attached comment a bit odd.   It's a very old meter and has been reviewed before including by Dave.  Imagine if the purpose was for damage control.      Seems we should address them... 


Dear Keysight, 
While I did make an attempt to contact you several years ago when I first became interested in looking at handheld meters, you refused to acknowledge me.   I am an independent reviewer and except in very rare cases, all of the products I have looked at were purchased out of pocket at my own expense.   My only interest is in how electrically robust these meters are when ran against a common set of tests.   A standard transient generator is used and there is very little human involvement.  In other words, there is no bias.    You can be assured that your product will be treated with the same care as any others I have looked at.   It will be ranked on how well it performs.   

PS, I hope you learned your lesson about using glass filled plastics for your function switch.   

[NoMoreMagicSmoke]

Earlier in the manual it only specifies it up to 9.9999 MHz... confused yet?

This isn't the only misleading wording. They did the same thing with accuracy and temperature coefficient. In one section they imply that the stated accuracy specifications are accurate over the whole range, but then later they list the temp coefficient when outside of 18-28C.

[joeqsmith]

One just describes the drift, which could be well within the accuracy.  Say for example, we wanted to compensate for that error to tighten the measurement.   

[Fungus]

Maybe I am the only one who found the attached comment a bit odd.   It's a very old meter and has been reviewed before including by Dave.

Very strange...