Test Equipment Anonymous (TEA) group therapy thread

[tggzzz]

In this case I'd recommend the 2635 or 2636, they are going down to 1fA. 

At an average of 1 electron every 150µs, the current flow becomes lumpy and digitised.

Use triax, and don't flex the cable while using it

[mnementh]

Got my 4145B/16058A accessories today...all nicely packaged....and the foam inside the "briefcase" was totally rotten. I effing hate this sticky smelly crap.   

Anyway, I dug it all out and replaced it with some foam I had saved. Not the prettiest, but a damn sight better than what was in there before. Not pictured are the set of flying leads for making connections inside the 16058A.

mnem
*desperately trying to cudgel his brain awake*

[shakalnokturn]

If you are going to play "What is it" try this one. Its a part I have and yes that is an SMA connector on the end.

As we've ruled out pitot tube (and presumably anything close and pressure related) then my list would include liquid cooled load/terminator, a flow cell of some sort, or (low probability from the connections) some sort of GDT type lightning arrestor.

+1 on the liquid cooled load.

[tggzzz]

If you are going to play "What is it" try this one. Its a part I have and yes that is an SMA connector on the end.

Antenna with preamp?

It looks like it's got 2 distinct "ports" / tubes to let the air in. And it's Robert so unless he is pervert and is on purpose trying to mislead us, then it's probably an aircraft part.  So.. some sensor in an aircraft that takes air in. But it's not an air speed / Pitot tube sensor. So.. maybe a sensor for an altimeter ??

Going along those lines, I'd choose a vario. But the "flask" looks a little small, they wouldn't need an SMA, and I'm not sure it is sealed.

[mnementh]

   Part of the day quiz, Leather medal for grabs

I too thought at first that it was a VFD of some sort... and given the shape of the active elements, it looked to me like robot eyes, maybe for some stoopit robot toy from the 80s or 90s...

Thanks for the archaeology lesson! 

mnem
 

[tggzzz]

   Part of the day quiz, Leather medal for grabs

I too thought at first that it was a VFD of some sort... and given the shape of the active elements, it looked to me like robot eyes, maybe for some stoopit robot toy from the 80s or 90s...

Thanks for the archaeology lesson! 

mnem
 

Not archaeology: RS have 41 in stock, at £43+VAT each. https://uk.rs-online.com/web/p/vacuum-tubes/1449016

[mnementh]

   Guess the part this time 

I'd guess some form of Hall sensor; 4 legs usually means the DAC is internal. We spent a lot of time tinkering with these on our RC transmitters back in the day. 

mnem
 

[bd139]

   Part of the day quiz, Leather medal for grabs

I too thought at first that it was a VFD of some sort... and given the shape of the active elements, it looked to me like robot eyes, maybe for some stoopit robot toy from the 80s or 90s...

Thanks for the archaeology lesson! 

mnem
 

Not archaeology: RS have 41 in stock, at £43+VAT each. https://uk.rs-online.com/web/p/vacuum-tubes/1449016

It’s more coprology with those things.

[BU508A]

This seller in the States (NAWTS) has 212 - 191 (already sold) in stock:

https://www.ebay.com/itm/222598731590

[mnementh]

Anybody can buy expensive chemicals to make the problem go away...

Sn18Pb32Bi50 (Rose Metal) is pretty cheap and melt at around 95C

Yeah, but as soon as you shop it made into a convenient-to-use wire form instead of globules, it gets much more expensive. Could be fun to find ways to cast it into useful forms with boiling water tho.

mnem
*knocks self unconscious with a rosin mallet*

Globules might be OK for desoldering applications. If not, then your rosin mallet might help change the shape

But would little Pb pancakes really be any good for the world...?

mnem
great... now you've got me imagining a whole regiment of tiny little Gallaghers with tiny little Sledge-O-Matics marching across my workbench...   

[Specmaster]

" Exclusive Preveiw " with exclusive Typo too ! 

Good Vince - that was a test to see if anyone was really looking! Congratulations! 

Beware! We had quite a few of these "always on" - after only a year a considerable number had gone bust; not only faded but missing lines and various glitches 
In general, blue OLED have the shortest lifetime of the "phosphor", yellow has AFAIK the longest.

Thanks. I might yet get a bigger screen, still playing with it.

Of course, it was 

[BU508A]

In this case I'd recommend the 2635 or 2636, they are going down to 1fA. 

and then realize you need triax everywhere.

Pscht!   

[mnementh]

https://www.newark.com/metcal/mx-ds1/desolder-hand-piece/dp/41B5513



Oh... yeah. And tweezers too. And custom heads for DIP8/14/20, etc... and all the cleaners and... and... 

mnem
 

A kings ransom to pay for them too?

I find that winding the temperature up a bit and adding a load of fresh solder helps a lot when working with large ground planes.

This is mostly for those playing along at home:

Yeah, that seems to be a common misconception here and everywhere soldering is discussed. There is a huge difference between cranking up the temperature vs delivering more heat. There is a reason we have big wide chisel tips with lots of mass and contact surface and tiny conical tips to reach tiny spots and almost every variant in between, even with conventional soldering irons. While you can make do by cranking up the heat on a smaller iron, it really is not the right way to do it, and often results in burning the substrate and lifting traces because right at the contact point you are delivering much too high a temperature to the work.

The difference with MetCal/SmartHeat and similar HF/inductive heating technology... and it really is something that has to be experienced to understand... is that it consistently delivers much more quantity of heat in a smaller tip than any resistive element iron is physically capable of doing.

You really do get a quantum level higher performance for your money.

The question then becomes one of budget vs need (or in my case, very limited space in my workbench bag) ; there simply is no question that if you can spend it, MetCal is worth every penny.

mnem
 

[McBryce]

Anyone looking for a €1000 plastic case? https://www.ebay.de/itm/114972031453

McBryce.

You would be too late for a Telequipment Oscilloscope Type D1011 front and back outer cover, which sold for £100 even though “I have no means of testing this unit”   .

https://www.ebay.co.uk/itm/Telequipment-Oscilloscope-Type-D1011-front-and-back-outer-cover-/363535705851

Yeah, the seller wouldn't ship  to Germany, so I had to let that one go

McBryce.

[tggzzz]

   Part of the day quiz, Leather medal for grabs

I too thought at first that it was a VFD of some sort... and given the shape of the active elements, it looked to me like robot eyes, maybe for some stoopit robot toy from the 80s or 90s...

Thanks for the archaeology lesson! 

mnem
 

Not archaeology: RS have 41 in stock, at £43+VAT each. https://uk.rs-online.com/web/p/vacuum-tubes/1449016

It’s more coprology with those things.

IIRC the data sheet indicates they are ideal for audiofools: 5.6kHz resonance and several parameters depend on the output load. Don't know how they manage that.

[mnementh]

Whoa, Spec.... that's kinda like deja vu'... kinda like deja vu'...

Nah, thats just Groundhog Day, when said he was having trouble measuring ESR etc, they were in circuit, I've had that scenario, but removing and suddenly things change, hence the question 

No, I was talking aboot the fact you double-quoted me here:

https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg3689017/#msg3689017

and figured you might wanna trim the excess mnem. 

mnem
pack a lunch; there's a lot to trim, and you'll be at it for a while...

[ch_scr]

   Part of the day quiz, Leather medal for grabs

I too thought at first that it was a VFD of some sort... and given the shape of the active elements, it looked to me like robot eyes, maybe for some stoopit robot toy from the 80s or 90s...

Thanks for the archaeology lesson! 

mnem
 

Not archaeology: RS have 41 in stock, at £43+VAT each. https://uk.rs-online.com/web/p/vacuum-tubes/1449016

It’s more coprology with those things.

IIRC the data sheet indicates they are ideal for audiofools: 5.6kHz resonance and several parameters depend on the output load. Don't know how they manage that.

Well I'd say the geometry is really ill-suited for a tube - it's a VFD after all, pressed into service...

[mnementh]

There is a Keithley 2602 SMU offered by zhoefler in the bay. Starting bid: 1190,- EUR (NAWTS)

https://www.ebay.de/itm/403162060138   

I give up. What is a system source device used for?

A digitally controlled power supply that can also measure it's voltage/current with 6 1/2 digits. And it's "4-quadrant" so +- on voltage and current - which also makes it an electronic load.

A true "swiss army knife". And two of them in one case! These range up to 20V/ 1.5A and 200V/0.1A. Also, they are priced like a small car...

These are the original non-letter units, long out of service. I have a similar "A" unit, but these are out of service as well. Only the newest "B" units still get service from keithley AFAIK.

Edit: I should add that they are superior to a normal DMM, as since they are power supplys you can set the current to zero - as long as you are inside the +-200V compliance range "no" current will flow in/out of the device - which makes them a lot higher impedance (infinite in theory) than the 10Meg of the usual DMM.

Yeah, Cerebus expounded in great detail on the joys of dev work with a Source Measure Unit when he bought his, but eevBlog search is being a complete useless whiny bitch today. 

It's like how we usually monitor a project with voltmeter/ammeter and a spaghetti of wires... only designed to do it all internally at very high precision and provide CV/CC power supply and generate graphs/logs of the testing which can be manipulated on your PC.

This level of precision even at low power usage makes it very valuable for characterizing the current/voltage demands of even single components within a design under changing operating conditions.

mnem
*currently having another pang of PSU envy*

[bd139]

   Part of the day quiz, Leather medal for grabs

I too thought at first that it was a VFD of some sort... and given the shape of the active elements, it looked to me like robot eyes, maybe for some stoopit robot toy from the 80s or 90s...

Thanks for the archaeology lesson! 

mnem
 

Not archaeology: RS have 41 in stock, at £43+VAT each. https://uk.rs-online.com/web/p/vacuum-tubes/1449016

It’s more coprology with those things.

IIRC the data sheet indicates they are ideal for audiofools: 5.6kHz resonance and several parameters depend on the output load. Don't know how they manage that.

Well I'd say the geometry is really ill-suited for a tube - it's a VFD after all, pressed into service...

It’s a terrible terrible tube. Get the datasheet and compare to a lowly 12AU7

However mikrowave1 got one working in the RF domain somehow:

[mnementh]

If you are going to play "What is it" try this one. Its a part I have and yes that is an SMA connector on the end.

A pitot tube?

I was going to guess some form of BMAP sensor... but that's pretty close to a pitot tube, so prolly not.

mnem
 

[tggzzz]

   Part of the day quiz, Leather medal for grabs

I too thought at first that it was a VFD of some sort... and given the shape of the active elements, it looked to me like robot eyes, maybe for some stoopit robot toy from the 80s or 90s...

Thanks for the archaeology lesson! 

mnem
 

Not archaeology: RS have 41 in stock, at £43+VAT each. https://uk.rs-online.com/web/p/vacuum-tubes/1449016

It’s more coprology with those things.

IIRC the data sheet indicates they are ideal for audiofools: 5.6kHz resonance and several parameters depend on the output load. Don't know how they manage that.

Well I'd say the geometry is really ill-suited for a tube - it's a VFD after all, pressed into service...

It’s a terrible terrible tube. Get the datasheet and compare to a lowly 12AU7

However mikrowave1 got one working in the RF domain somehow:

I don't watch yootoob vids as a rule, so I'll merely note that RF spectrum analysers traditionally start at 9kHz, presumably because of EMI/EMC regs.

[mnementh]

" Exclusive Preveiw " with exclusive Typo too ! 

Good Vince - that was a test to see if anyone was really looking! Congratulations! 

Beware! We had quite a few of these "always on" - after only a year a considerable number had gone bust; not only faded but missing lines and various glitches 
In general, blue OLED have the shortest lifetime of the "phosphor", yellow has AFAIK the longest.

Thanks. I might yet get a bigger screen, still playing with it.

Lifespan of OLEDs can be greatly increased by cranking down the drive current. The one in my soldering station is close to 3 years old and is on almost all day, as my "deep sleep" temp is set to 20°.

mnem
 

[mnementh]

" Exclusive Preveiw " with exclusive Typo too ! 

Good Vince - that was a test to see if anyone was really looking! Congratulations! 

Oh you pervert, it was deliberate ! 

Glad I passed the test ! I think I deserve a cookie now !

mnem
BBQ later...

[mnementh]

You used to be able to get that stuff in every colour under the sun, probably still can if you search hard enough but it's become a little hard to find presumably

Hmm OK, will search hard then ! I fear I might have to get paint custom mixed though, in the end, as I find it highly unlikely that some thing off the shelve would match the Tektronix colour closely enough to blend perfectly with the remaining/good parts of the face plate.  I fear this could become a bit of a rabbit hole for me...

Or you could just re-color all the engraved markings so they match.

mnem
 

[mnementh]

   Part of the day quiz, Leather medal for grabs

I too thought at first that it was a VFD of some sort... and given the shape of the active elements, it looked to me like robot eyes, maybe for some stoopit robot toy from the 80s or 90s...

Thanks for the archaeology lesson! 

mnem
 

Not archaeology: RS have 41 in stock, at £43+VAT each. https://uk.rs-online.com/web/p/vacuum-tubes/1449016

It’s more coprology with those things.

IIRC the data sheet indicates they are ideal for audiofools: 5.6kHz resonance and several parameters depend on the output load. Don't know how they manage that.

Well I'd say the geometry is really ill-suited for a tube - it's a VFD after all, pressed into service...

It’s a terrible terrible tube. Get the datasheet and compare to a lowly 12AU7

However mikrowave1 got one working in the RF domain somehow:

@tggzzz: Archaic device, archaic supplier; archaeology still applies.  Just like when I went digging round in that rabbit warren down south.


@bd139: Neat... it glows while it's working! That's... something...? 

mnem
also:  on egregious use of  Fahnestock clips.