Test Equipment Anonymous (TEA) group therapy thread

[Specmaster]

If I see those pendulums without having invited their owner I,'ll dance the nutcracker suite ...

LMAO 

[mnementh]

Northern Life Lesson number 267: Don't take a whizz off the back porch in February and forget aboot the frosty aluminum storm door! The wind WILL pick that moment to make itself known!

If I see those pendulums without having invited their owner I'll dance the nutcracker suite ...

LMAO 

Watch oot what promises you make. Some of us enjoy a little pain with our pleasure.

mnem
"sticks and stones may break my bones, but whips and chains excite me..."

[Saskia]

@mnem I can accomodate your desire for whips and pain, no sweat. Standard rate is 360 Euro Pesos /hour, TEA members get a 25% discount

[mansaxel]

I'd rather get my pain from TE.

As I was trying out my freshly recapped TF1041 VTVM yesterday, I noticed that one of the HT electrolytes was getting very hot. I'd accidentally fitted it polarity reversed.    It is no longer a snappy 10µF 450V capacitor, but a rather tired 3,24µF one. It did not blow, but it was hot enough that there was a small sliver of magic smoke emanating from it. I'd been prescient enough to buy a standard quantity, i.e. 10 pieces, so the Sad Caps Bag got a new tenant, a new cap was fitted -- correctly -- and the VTVM is not cooking anymore.  It is a bit better w.r.t. accuracy, but not good enough, so calibration and adjustment, as far as I have sources, will have to follow. 

Eternal trap I tend to fall into over and over again: Most of these VTVM -- regardless of make -- have an impressive amount of scales on their instruments, so one must be quite careful to look at the right one...

[med6753]

Eternal trap I tend to fall into over and over again: Most of these VTVM -- regardless of make -- have an impressive amount of scales on their instruments, so one must be quite careful to look at the right one...

Sounds very familiar. I thought the calibration on a Heath V-7A VTVM was way off until I realized I was looking at the wrong scale. 

Also done the same with a tant capacitor. They really don't like that and let you know immediately it is unhappy. 

[Specmaster]

@mansaxel, you dodged a bullet there for sure, you certainly don't want a cap spillings its guts, good job you spotted it in time, by the sounds of it, you caught in the nick of time as it had reached the starting point of the venting stage 

[factory]

...

Opened it up, only to find 2 Duracells in a very sorry state.  One of them was intact, but the other one had a serious case of Durchfall and shat its contents over itself, battery holder, and also left a string in the bottom of the case.  Both cells were around 680mV.  Fortunately the gunk cleaned up very easy, without a trace, and after rinsing the battery holder under running water and letting it dry out, fitting of new batteries restored both function and finish to the instrument.
...

Sounds like you dodged a bullet. Take it as a warning shot from Murphy. I will fill out the near miss incident report for you if you come join the NiMH club*. Like I always (OK, never) say, "Friends don't let friends use alkaline primary batteries in their test equipment."

* Yes, yes. ...if your meters support the lower voltage without crying.

Ni-MH are not immune to developing incontinence issues, here are some failed Sanyo Ni-MH AA found in a portable TV, no idea if they how old they are, or if they are genuine or not as this was bought second hand. A good reminder not to trust any battery and to remove them from stored items.






David

[factory]

@mansaxel, you dodged a bullet there for sure, you certainly don't want a cap spillings its guts, good job you spotted it in time, by the sounds of it, you caught in the nick of time as it had reached the starting point of the venting stage 

We have had a few incidents like that at work, they usually just vent out the top, I can remember one incident of a tiny replacement cap going bang in a switching supply, the engineer under-specced them. 

I've also successfully tested four Nichicon 2200uF 16V BT series caps for an entire four hours, they didn't blow, but had domed a bit, they got replaced with some more fitted correctly. 

David

[factory]

As promised some teardown pictures of the Tektronix 321 oscilloscope s/n 000861.

Overview with side covers removed.



Regulated power supply (10V) & charger circuit, some signs of previous repair work and many of the replacement parts are CV numbered (old UK mil coded parts).



Some signs of gorilla activity here, damaged ceramic terminal strip. 


PSU step up circuit, with replacement CV numbered transistors, the two large can caps are for the 10V regulated supply above.




And the line up of crusty caps on the secondary supply rails.


Part two to follow....

[med6753]

As promised some teardown pictures of the Tektronix 321 oscilloscope s/n 000861.

....snip

Part two to follow....

Similar in layout but I see many differences between your Type 321 and my Type 321A.

[Cerebus]

OT: Apple have added an Artificial Stupidity image classifier to IOS in the latest release. I was just taking a look at it. Overall as hit and miss as you might expect - it volunteered a list of supposed Dogs that was completely composed of cats (and one small pile of soft toys). What I find a bit worrying is what they must have been training it on. It also offered a list of photos of 'Food'.



I agree the Modigliani nude is "good enough to eat" but classifying it under food is a bit disturbing. What are the people at Apple eating, and would it be safe to accept a lunch invitation from them?

[mnementh]

Northern Life Lesson number 267: Don't take a whizz off the back porch in February and forget aboot the frosty aluminum storm door! The wind WILL pick that moment to make itself known!

If I see those pendulums without having invited their owner I'll dance the nutcracker suite ...

LMAO 

Watch oot what promises you make. Some of us enjoy a little pain with our pleasure.

mnem
"sticks and stones may break my bones, but whips and chains excite me..."

@mnem I can accomodate your desire for whips and pain, no sweat. Standard rate is 360 Euro Pesos /hour, TEA members get a 25% discount

I appreciate the offer, and next time I make it to the land of beer and brats I may take you up on it; though I'd probably more enjoy getting my hands dirty with some of your fireworks-fixins. 

But evidently nobody here grasped the full horror of my original predicament... the wind I alluded to blew said frosty storm door shut at the worst possible moment; think "tongue on a frosty flagpole" only the tenderest bit of any male's tender vittles.

mnem
It gets worse.

[mnementh]

OT: Apple have added an Artificial Stupidity image classifier to IOS in the latest release. I was just taking a look at it. Overall as hit and miss as you might expect - it volunteered a list of supposed Dogs that was completely composed of cats (and one small pile of soft toys). What I find a bit worrying is what they must have been training it on. It also offered a list of photos of 'Food'.



I agree the Modigliani nude is "good enough to eat" but classifying it under food is a bit disturbing. What are the people at Apple eating, and would it be safe to accept a lunch invitation from them?

I see some nice juicy melons, finger-lickin' good ribs, and sweet apple pie... no idea what's bothering you!

mnem
};=)~~~~<

[mnementh]

As predicted.......0 degrees C this morning and frost on the pumpkin. I missed my calling as a weatherperson. 

Damn you med... you and your damned weather advisory made me get my sorry arse out there this afternoon and put the snow tires on the Rav4. And of course only after I had everything dragged out and the car in the air did I find out that the one socket I need for the lugnuts has gone AWOL somewhere in the move.

Fortunately Home Despot is only a few minutes away... I only had to finish the last wheel in the dark by flashlight.

mnem
 

[mnementh]

   https://www.owon.com.hk/products_1_channel_oscilloscope

Wow... I think I may have just stumbled across a new contender for "bottom of the barrel oscilloscope"...

mnem
of course it can always get worse.

[mansaxel]

Eternal trap I tend to fall into over and over again: Most of these VTVM -- regardless of make -- have an impressive amount of scales on their instruments, so one must be quite careful to look at the right one...

Sounds very familiar. I thought the calibration on a Heath V-7A VTVM was way off until I realized I was looking at the wrong scale. 

Also done the same with a tant capacitor. They really don't like that and let you know immediately it is unhappy. 

"Thou shalt check voltages" -> Once I had the new cap in, I started looking at various voltages. The manual gives readings for AC secondary, DC high voltage,  and so on. All were low.  Studies of the manual while looking at the mains transformer gave that the unit was set for 250V mains. A healthy voltage, of which I approve, but it is not one my outlets serve up. Re-tying the primary side for 240 volts  (We're at 236ish volts AC here, so "240" fits best) made the secondaries crawl up to more sensible values.

By pure, sheer luck, the depicted one was the first voltage test I made after having adjusted for mains, and spent the warm-up period checking supply voltages.  I still will have to nudge the other ranges a fair bit, but this was borderline metrologasm.

[ Specified attachment is not available ]

[mnementh]

Submitted for Honorable Mention: The printer that will not die.


mnem
Just because I couldn't find anything else that matched the page number.

[med6753]

As predicted.......0 degrees C this morning and frost on the pumpkin. I missed my calling as a weatherperson. 

Damn you med... you and your damned weather advisory made me get my sorry arse out there this afternoon and put the snow tires on the Rav4. And of course only after I had everything dragged out and the car in the air did I find out that the one socket I need for the lugnuts has gone AWOL somewhere in the move.

Fortunately Home Despot is only a few minutes away... I only had to finish the last wheel in the dark by flashlight.

mnem
 

You can't blame me for your procrastination. 

[cyclin_al]

As predicted.......0 degrees C this morning and frost on the pumpkin. I missed my calling as a weatherperson. 

Damn you med... you and your damned weather advisory made me get my sorry arse out there this afternoon and put the snow tires on the Rav4. And of course only after I had everything dragged out and the car in the air did I find out that the one socket I need for the lugnuts has gone AWOL somewhere in the move.

Fortunately Home Despot is only a few minutes away... I only had to finish the last wheel in the dark by flashlight.

mnem
 

You can't blame me for your procrastination. 

Well, that is not very well thought out!

I can blame my procrastination on the dwagon.  I am not putting snow tires on my car until after this coming weekend.

There should be Nokian snow Tires on SWMBO's SUV before the weekend, in place of the summer Nokian Tyres...
In the worst case, I should have snow tires on the truck before the weekend.  Unfortunately, I doubt I will get that far through the list.

-- so why are we talking about snow tires?  It is still mountain biking season.  I just got back from a ride 

[Saskia]

tawkin bout TEA ...
will need to start packing up my stuff to prepare moving my equipment to the new house. Will most likely have to do a couple of truck tours (7.5 ton, I lost my semi permit when I turned 50 ...)
Yes, I could call in the professional movers, but I don't have 30 grand to burn.

[Peter_O]

[...]


I agree the Modigliani nude is "good enough to eat" but classifying it under food is a bit disturbing. What are the people at Apple eating, and would it be safe to accept a lunch invitation from them?

Seems we can rest assured with Apples approaches to assess user's health and mental state using AI and holding that data in the cloud and maybe selling it.     

[Robert763]

   https://www.owon.com.hk/products_1_channel_oscilloscope

Wow... I think I may have just stumbled across a new contender for "bottom of the barrel oscilloscope"...

mnem
of course it can always get worse.

 
I think that the intended market for that 'scope is education. It appears to be a replacement fo the simple CROs histrorically used. If you are teaching the fundamentals of the CRO this is the sort of instrument you need, given that not many CRTs are made today.
At least it simulates a classic CRO not a PC based DSO.

[med6753]

 
I think that the intended market for that 'scope is education. It appears to be a replacement fo the simple CROs histrorically used. If you are teaching the fundamentals of the CRO this is the sort of instrument you need, given that not many CRTs are made today.
At least it simulates a classic CRO not a PC based DSO.

Simulates but obviously isn't a true analog scope. There's all kinds of A/D gimmickry going on inside. That "130,000 wfms/s waveform capture rate" sounds impressive until you realize that a true analog CRO has a theoretical infinite capture rate.   

[Andrew_Debbie]

   https://www.owon.com.hk/products_1_channel_oscilloscope

Wow... I think I may have just stumbled across a new contender for "bottom of the barrel oscilloscope"...

mnem
of course it can always get worse.

The one channel AS101 is  "on promotion" at £104 from Banggood.     Google also found me a thread on EEVblog.


A 10MHz Picoscope 2204A can be had for less.  I've seen them for £80 at Amazon Warehouse.  £105 direct from Picotech.  It is dual channel, has protocol decode and other goodies.     On a £100 budget,  I'd get the Picoscope or the hand held 40Mhz Owon.

Past that there is the 100MHz Hantek DSO2x10 for around $200. 

[Specmaster]

But evidently nobody here grasped the full horror of my original predicament... the wind I alluded to blew said frosty storm door shut at the worst possible moment; think "tongue on a frosty flagpole" only the tenderest bit of any male's tender vittles.

mnem
It gets worse.

Then you think wrong my friend, I expect that I and a few others probably thought discretion might be the best part of valor and save the old dwagons blushes a bit more.