Test Equipment Anonymous (TEA) group therapy thread

[med6753]

This is OT but I don't know how else to resolve the problem. It seems that our index page is having problems the only way I get onto the forum is from a direct link in response to an email telling me of a new reply to a thread that I subscribe to. Once I get on the forum by clicking that link, I still cannot get access to the main index page, is anyone else having the same issues?

Yes, having same issue.

[Specmaster]

This is OT but I don't know how else to resolve the problem. It seems that our index page is having problems the only way I get onto the forum is from a direct link in response to an email telling me of a new reply to a thread that I subscribe to. Once I get on the forum by clicking that link, I still cannot get access to the main index page, is anyone else having the same issues?

Yes, having same issue.

Maybe its struggling because its been extra busy today, never known it to be so busy on a weekend before.

[med6753]

While I'm waiting for the parts to arrive for the Tek 465 I figured I'd revisit the Fluke 8000A DMM drift issue and power supply modifications. In my previous posts on the same subject I was able to show that I reduced overall warm up drift from approx 40mv to approx 20mv on the 20V DC range by installing 7815/7915 linear regulators on the +/- 15V supplies. Through discussions here it was recommended that additional drift reduction might be possible by regulating the currently unregulated +5V supply. So today a modeled a modification and I have the results.

To simulate a “real world” mod I decided to use an actual 7805 regulator. I disabled the unregulated Fluke supply and tacked in the 7805. The 7805 is fed by an external supply of +9V. The output of the 7805 is a steady +5.037V. The results are in the pictures. Pix 1 is right at power on. A steady +10.00V with only an occasional blip to +9.99V. Pix 2 is 1.5 hours later. Again, steady +10.00V with only an occasional blip to +10.01V. Conclusion: Any appreciable drift has been almost completely eliminated and this mod is worth it.    I don't have a suitably sized transformer to fit into the case so I'll have to order one. Once I do that I'll post pictures and a schematic of the modification.       

Awresome! I've abused 7805s and LM1117s similarly in oodles of repair/upgrade/mod projects; I often wonder why it wasn't the first thing to come to mind to the original designers. 78xx regulators aren't cliche'; they're basic building blocks, even if they do waste a few mW as heat.

Surely you have an old 8-16V wall wart you can gut for the transformer and rectifier?


mnem
*Working my way down the list*

I don't think linear voltage regulators were available (or were super expensive) when the 8000A was initially designed.

No wall warts laying around. I robbed them a long time ago for parts.

[mnementh]

So I powered it up. I do this now with a variac and monitoring the current while.

Ob reminder: don't do that with equipment that has a switched-mode power supply. The constant power output plus low input voltage implies a high input current.

I had a fight with me whether I should mention that this does not work work for switchers. But I decided that this was obvious.
But you're right, it is worth noting.
The input current is also close to nil until it suddenly springs to life. There's just no slow ramping up.

This is a good place for one of those now-outlawed incandescent light bulbs; in series as a current-limiting resistor. Pick a bulb rated around 75-150% the wattage of the DUT. Electronics weenies have been doing this since the days of Tesla; still a good way to save you some magic smoke.

I first learned the technique from the old German fellow who taught me the basics of electronics; he was a tube-era fixer right into the early age of digital. We made a test jig with an old-school ceramic lamp base specifically for servicing the old RCA TVs with a "chopper circuit"; this was an early form of SMPS, and I've used the technique with numerous SMPS devices and only rarely have an issue with shutdown mode oscillation.


Cheers,


mnem
*tzzzt*

[Neomys Sapiens]

I remember vaguely having seen the "Lehrbriefe" a long, long time ago (pictures of the cover, actually, not the real thing).  Are they available online?The book accompanying the EE2000 wasn't bad, either. Are they available online?
And I missed the PM3088 post. (Search finds nothing, Startpage also draws a blank. Sounds like a CRO?)
I still don't understand why Philips built such an incredible range of instruments with often rather similar features. There certainly was room for streamlining the portfolio. Or making a "best of both worlds". Pity.

Right in this thread, see here:
https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg1494187/#msg1494187
No CRO, Plasma DSO. 2Ch 40Ms/s 100MHz. Strange form factor like some early portable computers.
The Philips Lehrbriefe are only available second hand today AFAIK.

[bd139]

Another disappointing pile of "test gear" crap from China arrived today. Decided to see if this LCR meter was any good. Wound a T37-6 with 14 turns, expecting a 0.6uH inductance approximately. Measured up at 0.28uH. Hmm.

Dug through the cupboard and found a 1% Cornell Dubilier 100pF silver mica capacitor. Those things are rock solid stable over time.

What did I find? After numerous zeroings? Error!



 

[Mr. Scram]

Eh, close enough.

[nixiefreqq]

what is it goood for?  aaaabsolutely nothin'!

Damn it! I started today with a song quote and was tempted to put one in every posting. But most of them would have been too obscure, so I dropped the idea. I now wish I had followed up, anyway, even if no one spotted them.

Calling yourself nixiefrqq and passing up on that device would not have worked. You know you have to live up to it. 

no......seriously.  that picture is 5 or 6 years old, and it has only gotten worse since.

that damn wall - o - nixie could tip over and kill my redneck ass.

it is time to stop!

will have to change my signature to "the engineer formerly known as nixiefreqq".  (maybe there is a symbol that would express this?)

[mnementh]

[SNIP]
As to my PM, check in your message tab at the top of the page? I sent you a personal message on April 26, 2018, 11:11:14 am

Found it, responded tooya, apologies. 

mnem
D'OH!

[Specmaster]

Another disappointing pile of "test gear" crap from China arrived today. Decided to see if this LCR meter was any good. Wound a T37-6 with 14 turns, expecting a 0.6uH inductance approximately. Measured up at 0.28uH. Hmm.

Dug through the cupboard and found a 1% Cornell Dubilier 100pF silver mica capacitor. Those things are rock solid stable over time.

What did I find? After numerous zeroings? Error!



 

Get your self one of these three, I can thoroughly recommend them, they can be found on Ebay.

[mnementh]

I remember vaguely having seen the "Lehrbriefe" a long, long time ago (pictures of the cover, actually, not the real thing).  Are they available online?The book accompanying the EE2000 wasn't bad, either. Are they available online?
And I missed the PM3088 post. (Search finds nothing, Startpage also draws a blank. Sounds like a CRO?)
I still don't understand why Philips built such an incredible range of instruments with often rather similar features. There certainly was room for streamlining the portfolio. Or making a "best of both worlds". Pity.

Right in this thread, see here:
https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg1494187/#msg1494187
No CRO, Plasma DSO. 2Ch 40Ms/s 100MHz. Strange form factor like some early portable computers.
The Philips Lehrbriefe are only available second hand today AFAIK.

I see it on Amazon US... but not a translated version, so not a lot of use to this old fool.

mnem
glerp?

[bd139]

Get your self one of these three, I can thoroughly recommend them, they can be found on Ebay.

Plan.

Either that or one of the Peak ones ... will go and do some reading

[mnementh]

Another disappointing pile of "test gear" crap from China arrived today. Decided to see if this LCR meter was any good. Wound a T37-6 with 14 turns, expecting a 0.6uH inductance approximately. Measured up at 0.28uH. Hmm.

Dug through the cupboard and found a 1% Cornell Dubilier 100pF silver mica capacitor. Those things are rock solid stable over time.

What did I find? After numerous zeroings? Error!



 

I have one of those; it's the original "12864 component Tester" from a few years ago. It has HI & LO ranges for both Capacitance and Inductance; though low values even on the low range are still iffy if there's poor connection and/or the leads are long. They're much closer on electrolytics for sure, and the low range seems to be calibrated for MMLC SMD caps with their ultra-low ESR. I wonder if the inductance range is similarly calibrated against the most popular inductors out in the wild; I don't know what frequency it tests at.

It also seems to be optimized for short test leads (100-150mm) with alligators, AFTER ZERO-ING.

I've tested mine against my Atlas/Peak ESR70 meter and it appears pretty close; though I still haven't bought a DE-5000 to check any of them against.

if you have one, you could always dump the firmware and adjust the compensation table against some standards if you're feeling froggy. 


mnem
Frogs have more musical ability than most humans.

[GerryBags]

I slipped... and bought a 2465B. Another fixer upper, but I couldn't resist.... it's got Tek stickers and everything! 

[GerryBags]

There's also a Sony inventory barcode on the other side too.... hopefully it was well looked after while they had it. We'll see when it turns up. These are from the listing pics.

[Specmaster]

Get your self one of these three, I can thoroughly recommend them, they can be found on Ebay.

Plan.

Either that or one of the Peak ones ... will go and do some reading

The peak ones I have not found many good reports for them other then they are British products.The XJW01 I show is mine and its one of the early versions, the newer ones are different to look at and come in metal cases with proper buttons rather then membranes like mine. Mine has the look of a homemade product but works really well. Aliexpress also sell them and here is one such link for them that explains a bit about them. This one is a kit but like the T12, you buy them as kits and build them yourself or buy ready made, the choice is yours.

https://de.aliexpress.com/item/2018-neue-Auto-LCR-Digitale-Br-cke-Widerstand-Kapazit-t-Induktivit-t-ESR-Meter/32843384264.html?spm=a2g0x.search0104.3.18.712512520KHQNi&ws_ab_test=searchweb0_0%2Csearchweb201602_3_10152_10065_10709_10151_10344_10068_10130_10324_10342_5722912_10547_10325_10343_10340_10341_10548_5722612_10697_10696_10192_5722812_10190_10084_10083_10618_5722712_10307_10710_10301_10303_5711215_10059_10184_308_100031_10103_441_10624_10623_10622_5711315_10621_10620_5722512%2Csearchweb201603_25%2CppcSwitch_5&algo_expid=59290a39-3b83-4eeb-87a9-cf20f76ba121-2&algo_pvid=59290a39-3b83-4eeb-87a9-cf20f76ba121&transAbTest=ae803_2&priceBeautifyAB=0

[Cerebus]

that damn wall - o - nixie could tip over and kill my redneck ass.

Ah, so you're setting yourself up for the classic redneck last words then?

You reach over to press a button on the wall–O–nixie saying, "Hey y'all, watch this!".

[mnementh]

Another disappointing pile of "test gear" crap from China arrived today. Decided to see if this LCR meter was any good. Wound a T37-6 with 14 turns, expecting a 0.6uH inductance approximately. Measured up at 0.28uH. Hmm.

Dug through the cupboard and found a 1% Cornell Dubilier 100pF silver mica capacitor. Those things are rock solid stable over time.

What did I find? After numerous zeroings? Error!



 

Get your self one of these three, I can thoroughly recommend them, they can be found on Ebay.

   

I looked at the XJW01 almost a year ago; then it cost more than the DER EE DE-5000. I was intrigued by what appeared to be a proper shielded 4-wire Kelvin connection, but was leery when I saw it not appearing to be properly grounded in any of the models I looked at. Also, I found mention of a "newer, STM32" version with better firmware that supposedly tested at 100Hz/1KHz/10KHz, (translated schematics for both versions here) but couldn't find anyone promising THAT version on fleaBay, so ran, did not walk in the direction of the DE-5000.

I tripped over a listing FROM Amazon Deals for a couple customer return DE-5000s at 1/2 price, but I wibbled and when I came back they were gone. I camped out on the listing for several months, even set myself a price alert, but they didn't return at that price. 

 

I still don't find any but the STC12-driven version on fleaBay, but I'll admit this newer version with the extruded AL shell is tempting at ~$US70-80. I just find myself looking at the similar function Atlas/Peak LCR45 and knowing how well my ESR70 has served for so many years.



Anybody know anything about this $280 LCR Meter? Or this $350 one?




mnem
 *Still kicking myself*

[mnementh]

I slipped... and bought a 2465B. Another fixer upper, but I couldn't resist.... it's got Tek stickers and everything! 

Muahahaha! Another soul corrupted by my proselytizing of the 2465's virtues! 


mnem
Before long, my army of loyal 2465 addicts will be in place! Then NOTHING can stop me from taking over the Tri-State Area!!!

[mnementh]

Get your self one of these three, I can thoroughly recommend them, they can be found on Ebay.

Plan.

Either that or one of the Peak ones ... will go and do some reading

The peak ones I have not found many good reports for them other then they are British products.The XJW01 I show is mine and its one of the early versions, the newer ones are different to look at and come in metal cases with proper buttons rather then membranes like mine. Mine has the look of a homemade product but works really well. Aliexpress also sell them and here is one such link for them that explains a bit about them. This one is a kit but like the T12, you buy them as kits and build them yourself or buy ready made, the choice is yours.

[LCR Meter on AliEx]

I've had one of the Atlas/Peak ESR70s since they were brand-spanking new... AWESOME piece of kit, aside from the A123 cell powering it ALWAYS being out of stock when I need one except at the local Auto Parts Store where it costs $8.

that one on Aliex is available as a built kit with accessories here.



[EDIT]

Holy Sanctified Sheep Dip People! 400 pages!!!

[/EDIT]

mnem
*Back to my cave*

[med6753]

Muahahaha! Another soul corrupted by my proselytizing of the 2465's virtues! 


mnem
Before long, my army of loyal 2465 addicts will be in place! Then NOTHING can stop me from taking over the Tri-State Area!!!

Where you located? That term "tri-state area" usually refers to NJ, NY, and CT. I'm in New York State...Hudson Valley.

[mnementh]

Muahahaha! Another soul corrupted by my proselytizing of the 2465's virtues! 


mnem
Before long, my army of loyal 2465 addicts will be in place! Then NOTHING can stop me from taking over the Tri-State Area!!!

Where you located? That term "tri-state area" usually refers to NJ, NY, and CT. I'm in New York State...Hudson Valley.

I was referring to the Pittsburgh Tri-state area; where I grew up. Steelers fan Win, lose or Suck!   

That said... I currently reside in Houston, TX... but this will not stop me! 


mnem
And if I have to run roughshod over Heinz Doofenschmirtz and his inane robot, so be it!

[mnementh]

I remember vaguely having seen the "Lehrbriefe" a long, long time ago (pictures of the cover, actually, not the real thing).  Are they available online?The book accompanying the EE2000 wasn't bad, either. Are they available online?
And I missed the PM3088 post. (Search finds nothing, Startpage also draws a blank. Sounds like a CRO?)
I still don't understand why Philips built such an incredible range of instruments with often rather similar features. There certainly was room for streamlining the portfolio. Or making a "best of both worlds". Pity.

Right in this thread, see here:
https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg1494187/#msg1494187
No CRO, Plasma DSO. 2Ch 40Ms/s 100MHz. Strange form factor like some early portable computers.
The Philips Lehrbriefe are only available second hand today AFAIK.

I see it on Amazon US... but not a translated version, so not a lot of use to this old fool.

mnem
glerp?

Abe Books has both parts as well, shipping from Germany. Seems pretty cheap. Hope that helps anyone looking for it.


mnem
*Currently being mauled by two small children*

[Specmaster]

Another disappointing pile of "test gear" crap from China arrived today. Decided to see if this LCR meter was any good. Wound a T37-6 with 14 turns, expecting a 0.6uH inductance approximately. Measured up at 0.28uH. Hmm.

Dug through the cupboard and found a 1% Cornell Dubilier 100pF silver mica capacitor. Those things are rock solid stable over time.

What did I find? After numerous zeroings? Error!



 

Get your self one of these three, I can thoroughly recommend them, they can be found on Ebay.

   

I looked at the XJW01 almost a year ago; then it cost more than the DER EE DE-5000. I was intrigued by what appeared to be a proper shielded 4-wire Kelvin connection, but was leery when I saw it not appearing to be properly grounded in any of the models I looked at. Also, I found mention of a "newer, STM32" version with better firmware that supposedly tested at 100Hz/1KHz/10KHz, (translated schematics for both versions here) but couldn't find anyone promising THAT version on fleaBay, so ran, did not walk in the direction of the DE-5000.

I tripped over a listing FROM Amazon Deals for a couple customer return DE-5000s at 1/2 price, but I wibbled and when I came back they were gone. I camped out on the listing for several months, even set myself a price alert, but they didn't return at that price. 

 

I still don't find any but the STC12-driven version on fleaBay, but I'll admit this newer version with the extruded AL shell is tempting at ~$US70-80. I just find myself looking at the similar function Atlas/Peak LCR45 and knowing how well my ESR70 has served for so many years.



Anybody know anything about this $280 LCR Meter? Or this $350 one?




mnem
 *Still kicking myself*

What I like about the XJW01 is the fact that it can fully automatic or you operate manually. I find the auto mode is perfectly acceptable and the screen is illuminated and it displays 7 parameters about the item under test. You simply attach the kelvin clips to the part you want to test and it automatically detect if its a resistor, inductor or a capacitor and select the appropriate mode. The only think you need to do is select the frequency at which to test the capacitors at and thats a single button press that will scroll through the options of 100Hz, 1KHz or 7.8KHz which seems to fit in with most capacitor data sheets I've seen.

The Peak devices give a parameter at a time and you have to scroll through them to get to the one you want.

Of the 3 devices I have, I just did some tests on a known cap, resistor and an unknown inductor...

                                    Transparent case                   Black case                     XJW01
10uF                             10.32uF                                10.23uF                        9.74uF
                                    1.3ohm ESR                           0.84ohm ESR               1.39ohm ESR
                                    0.6% V Loss                           0.5 V Loss                   0.79% V Loss

3.298K                          3.261K                                  3.3K                            3.296K

Unknown Inductor
Pulled from PCB              .08mH                                  .08mH                         .07mH

The XJW01 is the go to tester on the bench the other 2 are useful for given approx values in circuit or as portables and they also have the added advantage of testing diodes and transistors including MOSFETS and will correctly identify the pin outs and the hfe.

So in practise there is very little between the results they present but sheer speed of testing the XJW01 is the clear winner.

There is connection between the screen on the BNC and mains earth so they are floating and the leakage to ground is 1.2v and that maybe more RF induced then actual mains leakage as the case is plastic on mine but the newer ones are extruded alloy but are powered via a wall wart and / or batteries.                         

[mnementh]

While I'm waiting for the parts to arrive for the Tek 465 I figured I'd revisit the Fluke 8000A DMM drift issue and power supply modifications. In my previous posts on the same subject I was able to show that I reduced overall warm up drift from approx 40mv to approx 20mv on the 20V DC range by installing 7815/7915 linear regulators on the +/- 15V supplies. Through discussions here it was recommended that additional drift reduction might be possible by regulating the currently unregulated +5V supply. So today a modeled a modification and I have the results.

To simulate a “real world” mod I decided to use an actual 7805 regulator. I disabled the unregulated Fluke supply and tacked in the 7805. The 7805 is fed by an external supply of +9V. The output of the 7805 is a steady +5.037V. The results are in the pictures. Pix 1 is right at power on. A steady +10.00V with only an occasional blip to +9.99V. Pix 2 is 1.5 hours later. Again, steady +10.00V with only an occasional blip to +10.01V. Conclusion: Any appreciable drift has been almost completely eliminated and this mod is worth it.    I don't have a suitably sized transformer to fit into the case so I'll have to order one. Once I do that I'll post pictures and a schematic of the modification.       

Awresome! I've abused 7805s and LM1117s similarly in oodles of repair/upgrade/mod projects; I often wonder why it wasn't the first thing to come to mind to the original designers. 78xx regulators aren't cliche'; they're basic building blocks, even if they do waste a few mW as heat.

Surely you have an old 8-16V wall wart you can gut for the transformer and rectifier?


mnem
*Working my way down the list*

I don't think linear voltage regulators were available (or were super expensive) when the 8000A was initially designed.

No wall warts laying around. I robbed them a long time ago for parts.

Oh yeah... I found the 8000A on radiomuseum.org, they say it was made circa 1972-76. 78xx regulators were probably 1980 or so; IIRC, developed by NSC.

Joking aside, PM me a snail mail address; I'll drop something in the post for you to tinker with. I'm currently sorting through a huge pile of just this sort of junk to archive or trash; I'm sure I have something appropriate. You need what, 300-500mA? IIRC, you said it also drives the LED panel, right?


mnem
I think that's the last of 'em.