Test Equipment Anonymous (TEA) group therapy thread

[factory]

ebay tat time.   HFM?!?   

For those playing along at home: eBay auction: #154830257268

Honestly, given how popular these scopes are, even at that price ($109.00 shipped to the US) lot of assache saved for the money. A nice little cottage industry for a niche market, as it were.  It would be nice if the cells were at least included, but then the shipping would increase exponentially, so... 

mnem
 

Circuit seems to be based on or is, the design mentioned in this thread  ; https://www.eevblog.com/forum/projects/li-ion-battery-pack-for-tektronix-222-and-224/msg951854/#msg951854
Bet the case is also on here somewhere, for those with 3Dprinters.
Having cells included might be a problem for some postage companies.

David

[Cerebus]

...
First is the firmware; how new a firmware you can get is directly dependent on the PCB in question.
...
The newer firmwares are for newer processors with more ROM,
...

Sorry, just a linguistic quirk that always annoys/throws me. Firmware is a mass noun without number, like butter, or snow. Mass nouns are uncountable. Contrast with countable nouns like cat, house, or coin.

One can't have "a firmware" or "firmwares". There is "firmware", there is "the firmware [for a particular device]" and there is a "collection [or set] of firmware", but there isn't a singular definitive or a plural. You get the same thing with "code" in the software sense. "Where's the code?" makes sense, "Show me the code.", so does "They have code for this.", but "They have codes for this." doesn't.

You can always tell when a politician is talking out of their arse about computers when you hear them say "codes" when they should have said "code".

Yeah... 

While I do in general agree with the "erosion of minimal standards" POV you've expressed here, in this case I'm going to call the "living language" argument, as whether or not we like the way usage evolves, eventually it becomes the norm, and therefore correct. 

In this case, in context, the terms have a known meaning, as a contraction or abbreviation for "how new a version of the firmware" or referring to "a grouping of many versions of a base firmware" that are in common usage.

Technology is advancing far faster than we have established language to describe it; we are going to have to learn to live with these "growing pains" type language inconsistency scenarios for a lot longer than I have time left on this mudball.

mnem

No, it's not the "living language" thing, or "context" or anything else you said, it's just that you're saying it wrong.  If you want to quibble about it I will refer you to my former chief sub-editor Teresa Taras; you might get out alive*. 

*Who am I kidding, I've seen Teresa metaphorically demolish a whole gang of men, each of them individually twice her size. The only time I've ever seen Teresa even weaken a bit is when she lost a tequila drinking contest to me - I was crowing for weeks.

[Vince]

Zener : 9 different values from 2.7V up to 30V, all from the ZPD series bar one, the 6.8V one which is a ZTK. Go figure.

The ZTY 6V8 diode is not a standard zener. It's a temperature compensated voltage reference. Basically a 6V2 zenner in series with a silicon diode. The positive temperature coefficent of the zener is cancelled by the negative of the diode.
If you check it wirh a DMM on diode check it will read open in both directions. This is because the two diodes are back to back. You have to check it in reverse with a current limited source of >7 V

It's a ZTK not ZTY.  I googled but didn't find any ZTY Zener series.

Anyway the ZTK datasheet does say that it's temperature compensated, I did note that yesterday when I pulled the datasheet, but didn't know what to think of it...I mean datasheet headlines often use all sorts of buzz words to make you believe that your very common this or that part, is extra-ordinary and so much better than the others.... so I always take it with a pinch of salt.

However they don't say that it uses an extra diode in there for compensation, and indeed when I measure it, there is none. It measures just like any regular Zener.
So they must use some other kind of mechanism to achieve that compensation...

Anyway, I didn't know that there were temperature compensated Zener diodes, never mind that, at least some of them, did that by adding an extra diode in there.
So... thanks for the info !

[mnementh]

Not TE, but maybe interesting to some. I've been looking at in-car mini-disc players, and came across this one.
It has more sockets in the back than the back of a socket shop!

   https://www.ebay.co.uk/itm/363645094456

Hmmm... How much of that is interfaces required for integration into factory vehicle computer systems...? I absolutely loathe how ignorantly most car manufacturers have integrated core mission-critical systems into the fucking entertainment center... instead of learning from the TESLA Carputer fustercluck, they're diving in balls deep and piling it on exponentially.

Before long, we're not going to have to worry about whether or not Russian hackers have compromised Air Force One (as seen on popular TV years ago) or a squadron of F-35s; we're going to have to worry about them having botnet control of millions of self-driving or nearly self-driving cars as remote-controlled drones already on American soil... 

mnem
 

[factory]

Don't know about anyone else on here, but I'm very dissatisfied with the price of this digital VOM, 
https://www.ebay.co.uk/itm/313870712122


David

[mnementh]

You really need to look into one of those cheap Chinese component tester. Many of the newer ones will ID Zeners up to 8-15V, and most will identify switching (1N4148, etc) diodes as well, or at least give enuf parameters you can figure that out.

I wholeheartedly recommend the ESR02; offered under many brands but always looks like this in maroon or black. If you shop carefully, you should be able to pick it up with tweezer probes for US$25-35 equiv. Flexibility and more importantly, usability (usable sockets, SMD testbed and tweezer options) put the value off the hook.

https://www.amazon.com/Transistor-Component-Capacitor-Inductance-Electric/dp/B08PDKVWLZ/

mnem

I am not sure I understand ? Other than the fancy case, it looks like the usual cheap tester everybody has ? I already have one, you can see it in the picture above... it does not have a case so I could get it cheaper, but it looks to be no more no less than your fancy one ?!

I love it  but in the case of this mountain of diodes, it would not have helped me in the slightest : I already know they are diodes, and I already know the pinout, the cathode is clearly marked... what I need to know is the actual part number on them so I can sort them, label them, and pull the datasheet. The tester can't do that...

For basic diode testing any old multimeter is fine. For serious diode testing, there's no substitute for a good power supply, a good multimeter, and a pen and paper. Well, there is a curve tracer I suppose, but good ones are very expensive.

Don't forget Octopus (component tester). They are easy to build and with the right transfo could reach higher voltage (24 or 48V ?).

The one I built a while ago only goes up to 12V though. Combined to my 12Bits USB scope, I get interesting results.
https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg2723020/#msg2723020

More info on octopus here: http://www.arrl.org/files/file/QEX_Next_Issue/May-June2017/Ferreora.pdf

I recently uncovered the one I made in tech school (based on the EICO Junction Curve Tracer) and kept for many years on the back bench connected to that veteran Hitachi V212 scope.

Oh, gawd it is ugleeeee!   

mnem

[factory]

You really need to look into one of those cheap Chinese component tester. Many of the newer ones will ID Zeners up to 8-15V, and most will identify switching (1N4148, etc) diodes as well, or at least give enuf parameters you can figure that out.

I wholeheartedly recommend the ESR02; offered under many brands but always looks like this in maroon or black. If you shop carefully, you should be able to pick it up with tweezer probes for US$25-35 equiv. Flexibility and more importantly, usability (usable sockets, SMD testbed and tweezer options) put the value off the hook.

https://www.amazon.com/Transistor-Component-Capacitor-Inductance-Electric/dp/B08PDKVWLZ/

mnem

I am not sure I understand ? Other than the fancy case, it looks like the usual cheap tester everybody has ? I already have one, you can see it in the picture above... it does not have a case so I could get it cheaper, but it looks to be no more no less than your fancy one ?!

I love it  but in the case of this mountain of diodes, it would not have helped me in the slightest : I already know they are diodes, and I already know the pinout, the cathode is clearly marked... what I need to know is the actual part number on them so I can sort them, label them, and pull the datasheet. The tester can't do that...

For basic diode testing any old multimeter is fine. For serious diode testing, there's no substitute for a good power supply, a decade resistor, a good multimeter, and a pen and paper. Well, there is a curve tracer I suppose, but good ones are very expensive.

FTFY
By accident I found the TTI bench PSU (30V 2A) at work, would quite happily EOL Zener diodes when switched on, due to the output capacitance.  A decade box in series was needed to test Zeners, to avoid them ending up shorted.

The Megger used with a DVM, was good for checking high voltage Zeners too, we had some rated at 100V or was it 150V, I can't remember, the Megger did find some ordinary diodes that had been incorrectly fitted by someone else, reverse voltage was much higher than expected. 

David

[Vince]

Don't know about anyone else on here, but I'm very dissatisfied with the price of this digital VOM, 
https://www.ebay.co.uk/itm/313870712122


David

Hmmm that's a weird / interesting unit you have here ! It bears TWO differetn HP logos and model numbers ?!
There is one for the upper half of the instrument that says "Display" and another badge for the lower half, the meter itself ! 

Does that mean HP sold the instrument without display, just the lower half part, and it was up to the buyer to buy the top / display half of the instrument ?! 

But the design is not modular... a single case for both halves...  and what's the point of selling a voltmeter with no display ? It's not usable...

Help me.... understand...  the concept here.... 

[mnementh]

Yeah... 

While I do in general agree with the "erosion of minimal standards" POV you've expressed here, in this case I'm going to call the "living language" argument, as whether or not we like the way usage evolves, eventually it becomes the norm, and therefore correct. 

In this case, in context, the terms have a known meaning, as a contraction or abbreviation for "how new a version of the firmware" or referring to "a grouping of many versions of a base firmware" that are in common usage.

Technology is advancing far faster than we have established language to describe it; we are going to have to learn to live with these "growing pains" type language inconsistency scenarios for a lot longer than I have time left on this mudball.

mnem

No, it's not the "living language" thing, or "context" or anything else you said, it's just that you're saying it wrong.  If you want to quibble about it I will refer you to my former chief sub-editor Teresa Taras; you might get out alive*. 

*Who am I kidding, I've seen Teresa metaphorically demolish a whole gang of men, each of them individually twice her size. The only time I've ever seen Teresa even weaken a bit is when she lost a tequila drinking contest to me - I was crowing for weeks.

And yet, the language still changes, and history will ultimately write the epitaph of all these arguments over what language is right or wrong.

As I said... in general, I do agree with the "erosion of minimal standards" POV you've expressed... we're on the same side here. It really is no more than the "quirk" you've described it as.

Not gonna pull on that thread.     I love a good argument as much as the next dwagon, but I think I'm gonna save that energy for the Discord, and for fixing my BBQ grill. 

mnem
mmmm... I could weld that grate support... 

[Robert763]

Zener : 9 different values from 2.7V up to 30V, all from the ZPD series bar one, the 6.8V one which is a ZTK. Go figure.

The ZTY 6V8 diode is not a standard zener. It's a temperature compensated voltage reference. Basically a 6V2 zenner in series with a silicon diode. The positive temperature coefficent of the zener is cancelled by the negative of the diode.
If you check it wirh a DMM on diode check it will read open in both directions. This is because the two diodes are back to back. You have to check it in reverse with a current limited source of >7 V

It's a ZTK not ZTY.  I googled but didn't find any ZTY Zener series.

Anyway the ZTK datasheet does say that it's temperature compensated, I did note that yesterday when I pulled the datasheet, but didn't know what to think of it...I mean datasheet headlines often use all sorts of buzz words to make you believe that your very common this or that part, is extra-ordinary and so much better than the others.... so I always take it with a pinch of salt.

However they don't say that it uses an extra diode in there for compensation, and indeed when I measure it, there is none. It measures just like any regular Zener.
So they must use some other kind of mechanism to achieve that compensation...

Anyway, I didn't know that there were temperature compensated Zener diodes, never mind that, at least some of them, did that by adding an extra diode in there.
So... thanks for the info !

Thanks for shouting out my typo. Maybe I should not bother replying to your posts. I don't mind being corrected but does it have to be in bold oversized font? 

Back to the diode, what forward voltage does it read with a DMM on didoe test? If more than 600 mV it likely uses the series junction compension scheme. It is possible that they use two back-back junctions in series with the zener. This may be to get around patents or just a feature of how the device is constructed in silicon. Some are made using a transistor type structure.

[med6753]

ebay tat time.   HFM?!?   

For those playing along at home: eBay auction: #154830257268

Honestly, given how popular these scopes are, even at that price ($109.00 shipped to the US) lot of assache saved for the money. A nice little cottage industry for a niche market, as it were.  It would be nice if the cells were at least included, but then the shipping would increase exponentially, so... 

mnem
 

Circuit seems to be based on or is, the design mentioned in this thread  ; https://www.eevblog.com/forum/projects/li-ion-battery-pack-for-tektronix-222-and-224/msg951854/#msg951854
Bet the case is also on here somewhere, for those with 3Dprinters.
Having cells included might be a problem for some postage companies.

David

Did not realize that the 222 used a completely different battery scheme than the 221. But I guess it makes sense since the 222 has all the additional digital circuitry. So rather than having 5 pounds of shit stuffed into a 2 pound bag the 222 has 10 pounds stuffed into that 2 pound bag.  Given that working on the 221 was a pain I can only imagine the nightmare inside the 222.

BTW....the 221 is very happy with the NiMh conversion.   

[Robert763]

Don't know about anyone else on here, but I'm very dissatisfied with the price of this digital VOM, 
https://www.ebay.co.uk/itm/313870712122


David

Hmmm that's a weird / interesting unit you have here ! It bears TWO differetn HP logos and model numbers ?!
There is one for the upper half of the instrument that says "Display" and another badge for the lower half, the meter itself ! 

Does that mean HP sold the instrument without display, just the lower half part, and it was up to the buyer to buy the top / display half of the instrument ?! 

But the design is not modular... a single case for both halves...  and what's the point of selling a voltmeter with no display ? It's not usable...

Help me.... understand...  the concept here.... 

Why not just do some research?
Hint: there were also various counter modules and the two halves come apart without tools. Also this dates from when logic and LEDs we now buy for pennies were very expensive....

Edit: OK big hint http://hparchive.com/Manuals/HP-3470-Manual.pdf

[factory]

Don't know about anyone else on here, but I'm very dissatisfied with the price of this digital VOM, 
https://www.ebay.co.uk/itm/313870712122


David

Hmmm that's a weird / interesting unit you have here ! It bears TWO differetn HP logos and model numbers ?!
There is one for the upper half of the instrument that says "Display" and another badge for the lower half, the meter itself ! 

Does that mean HP sold the instrument without display, just the lower half part, and it was up to the buyer to buy the top / display half of the instrument ?! 

But the design is not modular... a single case for both halves...  and what's the point of selling a voltmeter with no display ? It's not usable...

Help me.... understand...  the concept here.... 

They top & bottom halves do indeed separate, there was a choice of 4.5 or 5.5 digit display modules and various lower modules for DVM, D-VOM, DMM and even a thermometer module.
None of mine came with the obscene price tag though, have two working 34740A display, a broken 34750A display, two working 2802A thermometer modules and a broken 34702A D-VOM module.


They made a counter system in the same way, 6 or 8 digit display, with choice of counter, universal counter and a DVM module for that. Haven't got a pic of mine, but its only the 6 digit 5300A with 10MHz 5301A counter module.

David

[Robert763]

ebay tat time.   HFM?!?   

For those playing along at home: eBay auction: #154830257268

Honestly, given how popular these scopes are, even at that price ($109.00 shipped to the US) lot of assache saved for the money. A nice little cottage industry for a niche market, as it were.  It would be nice if the cells were at least included, but then the shipping would increase exponentially, so... 

mnem
 

Circuit seems to be based on or is, the design mentioned in this thread  ; https://www.eevblog.com/forum/projects/li-ion-battery-pack-for-tektronix-222-and-224/msg951854/#msg951854
Bet the case is also on here somewhere, for those with 3Dprinters.
Having cells included might be a problem for some postage companies.

David

Did not realize that the 222 used a completely different battery scheme than the 221. But I guess it makes sense since the 222 has all the additional digital circuitry. So rather than having 5 pounds of shit stuffed into a 2 pound bag the 222 has 10 pounds stuffed into that 2 pound bag.  Given that working on the 221 was a pain I can only imagine the nightmare inside the 222.

BTW....the 221 is very happy with the NiMh conversion.   

The 222 is a completly different beast from the 221 etc. The only thing in commom is the basic form factor. They are literlly decades apart.

[Kosmic]

First is the firmware; how new a firmware you can get is directly dependent on the PCB in question. The older bare-board designs are way cheaper for a reason: Nobody is developing new FW for them anymore, because the hardware is too primitive.

The newer firmwares are for newer processors with more ROM, and more complex FW with a larger database and more sophisticated testing. The ESR02 is one of the newest families of the "cheap Chinesium component testers", and it simply has one of the best developed FWs out there until you get into serious HW like the DE-5000 and PEAK/Atlas ESR70Plus, which I also own.

Don't get fooled by the nice enclosure. My ESR02 came with an old and fairly limited version of the opensource firmware. I update to version 1.45m from madires (https://github.com/madires/Transistortester-Warehouse) and that was a lot better.

On the hardware side of things the ESR02 is not the best one you can find. GM328A would be better but less visually attractive. See the comparison of the different clones over here.
https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf

[mnementh]

ebay tat time.   HFM?!?   

For those playing along at home: eBay auction: #154830257268

Honestly, given how popular these scopes are, even at that price ($109.00 shipped to the US) lot of assache saved for the money. A nice little cottage industry for a niche market, as it were.  It would be nice if the cells were at least included, but then the shipping would increase exponentially, so... 

mnem
 

Circuit seems to be based on or is, the design mentioned in this thread  ; https://www.eevblog.com/forum/projects/li-ion-battery-pack-for-tektronix-222-and-224/msg951854/#msg951854
Bet the case is also on here somewhere, for those with 3Dprinters.
Having cells included might be a problem for some postage companies.

David

Circuit board design based upon the work of Kitsune-Denshi. licensed under the Creative Commons Attribution-ShareAlike License. Case design based upon the work of NearFarMedia on Thingiverse licensed under the Creative Commons Attribution License.

Kitsune-Denshi's project is primarily a 3DP project leveraging two commonly available 18650 power commodity PCBs as "Electronic Legos" into a finished product. A lot of "fiddly bits" type problem solving in this product, including light pipes to bring the status LEDs to the front panel as a proper solution should have, and a custom PCB to make it one piece as well. 

As I said... just looking at it from a 3DP "maker" perspective, I can see a lot of assache saved by just paying that $100 bux... for many people, I think it would be a bargain. Having just recently completed a similar project, the iterative design part alone is many afternoons of painstaking work.

[Cerebus]

Thanks for shouting out my typo. Maybe I should not bother replying to your posts. I don't mind being corrected but does it have to be in bold oversized font? 

It's not a typo, it's a literal; stop trying to deflect blame onto the typographer. 

To be fair to Vince, if one is trying to draw attention to what one is referring to in a body of text it can be quite difficult to make it sufficiently differentiated by simple bolding or whatever. On the other hand, if one makes the effort to do a bit of judicious snipping then all that's need is a simple typographical emphasis.

In other news: My car's wiper motor has packed up. Fault traced (thanks to a suitably rugged yellow Fluke 27 that I'm not scared to put near a circuit connected to a big lead acid battery) and unfortunately it really is a failed wiper motor, not just a 10 minute electrical fix. Looks like a combination of water ingress and  poor design of drainage points.

It looks like rain for most of the rest of the week from tomorrow so I'm off the road until I can get a replacement and fit it/get it fitted. Pah!

[Neper]

It looks like rain for most of the rest of the week from tomorrow so I'm off the road until I can get a replacement and fit it/get it fitted. Pah!

In the good old days one would have driven to the next cluster of scrapyards (dunno why but we always had them in clusters) and get a replacement.

[med6753]

In other news: My car's wiper motor has packed up. Fault traced (thanks to a suitably rugged yellow Fluke 27 that I'm not scared to put near a circuit connected to a big lead acid battery) and unfortunately it really is a failed wiper motor, not just a 10 minute electrical fix. Looks like a combination of water ingress and  poor design of drainage points.

It looks like rain for most of the rest of the week from tomorrow so I'm off the road until I can get a replacement and fit it/get it fitted. Pah!

Per chance a Lucas motor?  Prince of wiperless? 

[Vince]

Zener : 9 different values from 2.7V up to 30V, all from the ZPD series bar one, the 6.8V one which is a ZTK. Go figure.

The ZTY 6V8 diode is not a standard zener. It's a temperature compensated voltage reference. Basically a 6V2 zenner in series with a silicon diode. The positive temperature coefficent of the zener is cancelled by the negative of the diode.
If you check it wirh a DMM on diode check it will read open in both directions. This is because the two diodes are back to back. You have to check it in reverse with a current limited source of >7 V

It's a ZTK not ZTY.  I googled but didn't find any ZTY Zener series.

Anyway the ZTK datasheet does say that it's temperature compensated, I did note that yesterday when I pulled the datasheet, but didn't know what to think of it...I mean datasheet headlines often use all sorts of buzz words to make you believe that your very common this or that part, is extra-ordinary and so much better than the others.... so I always take it with a pinch of salt.

However they don't say that it uses an extra diode in there for compensation, and indeed when I measure it, there is none. It measures just like any regular Zener.
So they must use some other kind of mechanism to achieve that compensation...

Anyway, I didn't know that there were temperature compensated Zener diodes, never mind that, at least some of them, did that by adding an extra diode in there.
So... thanks for the info !

Thanks for shouting out my typo. Maybe I should not bother replying to your posts. I don't mind being corrected but does it have to be in bold oversized font? 

Wow !!!    That bad ?! You act as if I had a history of aggressing you ! I thought that rather I had always welcomed and been grateful every time you shared some of your knowledge with me ! 
I would have hope I would enjoy the benefit of the doubt here... oh well 

Since you clearly misunderstood my intent here, and I am not at all teh evil you suggest.. I have no choice but use some bandwidth to "justify" myself and tell you what went through my mind at that time. Hopefully that will clear things up 

So here goes, in chronological order, millisecond by millisecond as it unfolds in my neurons :

1) Rob gives an interesting info,  as he often does, that's nice.
2) Oh, didn't know about the special Zener diodes he is talking ab out, interesting, nice of him, as per usual from him.
3) Oh, I see he is not talking about my ZTK but rather another series.
4) Cool let's go look it up and learn something.
5) Shit can't find it, bummer.
6) Maybe It's an uncommon series and I need to Google for more than 2 seconds to find it.
7) Maybe he made a typo and he meant some other series.
8 ) He can't mean the ZTK I have, because clearly it does not have a built in extra diode in there, according to the datasheet.
9) Obviously he knows that, he is the clever one here, not me.
10) I ma sure there must be lots of  " Z " something series, and it's all too esy to make a typo and ruin your day.
11) If he says there is a Z series with this back to back extra diode, then I havre zero reason to doubt that, because he knows what is talking about and if he didn't, he would not have posted to tell me about these type of Zener.

12) So in conclusion, I decided to emphasize the series he is talking about so that I clear that up, and he can tell me either :

12.1) " Yes Vince, I do mean ZTY not ZTK. I am not surprised you failed to find the datasheet on  a quick search because it's uncommon or obsolete and the datasheet is hard to find. But I have a copyt of it , here it is ". In which case  cool I could look at the datasheet and learn more about it, and learn something.

12.2) " Oops sorry I didn't mean ZTY I mean ZAP ( or ZYB or ZUR or whatever other series that might exist out there)"... in which case I would say oh thanks, will go look it up immediately to learn more about it !


That's all there was to it really ! 

Back to the diode, what forward voltage does it read with a DMM on didoe test? If more than 600 mV it likely uses the series junction compension scheme. It is possible that they use two back-back junctions in series with the zener. This may be to get around patents or just a feature of how the device is constructed in silicon. Some are made using a transistor type structure.

I measure 700mV, give or take 5mV....

[mnementh]

First is the firmware; how new a firmware you can get is directly dependent on the PCB in question. The older bare-board designs are way cheaper for a reason: Nobody is developing new FW for them anymore, because the hardware is too primitive.

The newer firmwares are for newer processors with more ROM, and more complex FW with a larger database and more sophisticated testing. The ESR02 is one of the newest families of the "cheap Chinesium component testers", and it simply has one of the best developed FWs out there until you get into serious HW like the DE-5000 and PEAK/Atlas ESR70Plus, which I also own.

Don't get fooled by the nice enclosure. My ESR02 came with a old and fairly limited version of the opensource firmware. I update to version 1.45m from madires (https://github.com/madires/Transistortester-Warehouse) and that was a lot better.

On the hardware side of things the ESR02 is not the best one you can find. See the comparison of the different clones over here.
https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf

That site is one of several resources I refer to in my assessment of these things.  As I said, the core reason I promote the ESR02 is that its overall usability beats the others all hollow.

The hardware is one of the newest out there and therefore supports the newer firmware, and I disagree with many reviewers' insistence that those fucking POS ZIF sockets are a "must-have". These things always come with the cheapest possible one you can get, and replacing that with a decent one instantly doubles the cost of the unit unless you happen to have one on hand as surplus.

Even with a good ZIF socket, you don't get as reliable contact as the self-aligning component socket on the ESR02. A ZIF socket is not meant for use with fat and variable diameter transistor, capacitor and diode legs, etc... it is meant for DIP component legs of fixed and relatively thin dimensions. And if you wiggle the legs under compression to get a good contact, you eventually damage the socket, adding more cost.

After using over a dozen different versions of these testers, IMO the ZIF socket is a liability rather than a must-have.

After that, is that even on models which have an integrated SMD pad like the ESR02, it is always buried in close proximity to that gawddamn ZIF socket, such that using the SMD pad is a complete pain in the ass.

When you combine how much more usable the front panel of the ESR02 is with the fact it supports one of the newest versions of the commonly available Chinesium Component Tester firmware out there, I still think that even at $7-12 more, it is clearly a better value.

mnem
 

[med6753]

The 222 is a completly different beast from the 221 etc. The only thing in commom is the basic form factor. They are literlly decades apart.

I've not seen the internals to the 222 but I would have to assume that since it's a much later model that the level of integration could possibly be as much as 5X. But given that it essentially has an external battery pack does not bode well to what possibly could be inside the case.   

[Vince]

Don't know about anyone else on here, but I'm very dissatisfied with the price of this digital VOM, 
https://www.ebay.co.uk/itm/313870712122


David

Hmmm that's a weird / interesting unit you have here ! It bears TWO differetn HP logos and model numbers ?!
There is one for the upper half of the instrument that says "Display" and another badge for the lower half, the meter itself ! 

Does that mean HP sold the instrument without display, just the lower half part, and it was up to the buyer to buy the top / display half of the instrument ?! 

But the design is not modular... a single case for both halves...  and what's the point of selling a voltmeter with no display ? It's not usable...

Help me.... understand...  the concept here.... 

They top & bottom halves do indeed separate, there was a choice of 4.5 or 5.5 digit display modules and various lower modules for DVM, D-VOM, DMM and even a thermometer module.
None of mine came with the obscene price tag though, have two working 34740A display, a broken 34750A display, two working 2802A thermometer modules and a broken 34702A D-VOM module.


They made a counter system in the same way, 6 or 8 digit display, with choice of counter, universal counter and a DVM module for that. Haven't got a pic of mine, but its only the 6 digit 5300A with 10MHz 5301A counter module.

David

Thank you very much ! 

[tggzzz]

In other news: My car's wiper motor has packed up. Fault traced (thanks to a suitably rugged yellow Fluke 27 that I'm not scared to put near a circuit connected to a big lead acid battery) and unfortunately it really is a failed wiper motor, not just a 10 minute electrical fix. Looks like a combination of water ingress and  poor design of drainage points.

I had a wiper motor like that once, with the MoT due.

Once I had checked that the wording was "if fitted, windscreen wipers must work", the solution was simple. Yes, it passed

[Kosmic]

First is the firmware; how new a firmware you can get is directly dependent on the PCB in question. The older bare-board designs are way cheaper for a reason: Nobody is developing new FW for them anymore, because the hardware is too primitive.

The newer firmwares are for newer processors with more ROM, and more complex FW with a larger database and more sophisticated testing. The ESR02 is one of the newest families of the "cheap Chinesium component testers", and it simply has one of the best developed FWs out there until you get into serious HW like the DE-5000 and PEAK/Atlas ESR70Plus, which I also own.

Don't get fooled by the nice enclosure. My ESR02 came with a old and fairly limited version of the opensource firmware. I update to version 1.45m from madires (https://github.com/madires/Transistortester-Warehouse) and that was a lot better.

On the hardware side of things the ESR02 is not the best one you can find. See the comparison of the different clones over here.
https://github.com/madires/Transistortester-Warehouse/blob/master/Documentation/English/Clone-Comparison-Chart.pdf

That site is one of several resources I refer to in my assessment of these things.  As I said, the core reason I promote the ESR02 is that its overall usability beats the others all hollow.

The hardware is one of the newest out there and therefore supports the newer firmware, and I disagree with many reviewers' insistence that those fucking POS ZIF sockets are a "must-have". These things always come with the cheapest possible one you can get, and replacing that with a decent one instantly doubles the cost of the unit unless you happen to have one on hand as surplus.

Even with a good ZIF socket, you don't get as reliable contact as the self-aligning component socket on the ESR02. A ZIF socket is not meant for use with fat and variable diameter transistor, capacitor and diode legs, etc... it is meant for DIP component legs of fixed and relatively thin dimensions. And if you wiggle the legs under compression to get a good contact, you eventually damage the socket, adding more cost.

After using over a dozen different versions of these testers, IMO the ZIF socket is a liability rather than a must-have.

After that, is that even on models which have an integrated SMD pad like the ESR02, it is always buried in close proximity to that gawddamn ZIF socket, such that using the SMD pad is a complete pain in the ass.

When you combine how much more usable the front panel of the ESR02 is with the fact it supports one of the newest versions of the commonly available Chinesium Component Tester firmware out there, I still think that even at $7-12 more, it is clearly a better value.

mnem
 

Yes the form factor of the ESR02 is nice. The main reason why I bought mine. The firmware, on the other hand, is not really a selling point.