Test Equipment Anonymous (TEA) group therapy thread

[med6753]

So it's show us your mugs day? How come I never get these memos? 

[mnementh]

A liter?! Can't really believe that, does not look that large.

That's just a guess, based on my Dragon paw mugs, which are 20 oz... let me go find a measuring cup... 

mnem
 

This is my mug, when I'm in need of huge amounts of coffee. Capacity: 850ml

https://www.amazon.de/Bada-Bing-Kaffeebecher-Matheformeln-Kaffeetasse/dp/B07DVKZD3Q


There's a little riddle: on that cup, there is a tiny mistake. Can you spot it? 

No.

mnem
and that is a correct answer.

[Vince]

HOLD ON A MINUTE !!!! 


I wasn't 100% done with my diodes... still had my small Zener diodes to process. Well I had already bagged them up and labeled based solely on what was marked on them, but I didn't pull the datasheet to look at the specs in detail. So I did just that.

I have BZX, ZPD, ZPY and ZTK temperature compensated series. Easy.

But have also two that cause me trouble :

1)

" BYV 10 50 " ... looks all the world like a 10V Zener, tiny blue glass package, but can't find a datasheet for that. Plus, I tested it and it's not a 10V Zener... went up to 30Volts, what the lab supply allows.
So instead it looks like I might be mistaken and instead it's a not a Zener but more likely a BYV10-50 diode. BYV10 does exist, and it's a Schottky diode, 1Amp. DMM says yes it's likely to be right since they drop 0.165V. But...  the datasheets I can find say that a BYV10-50 does NOT exist. Only the 20/30/40 which represents the max reverse voltage. OK the datasheet is old and my diodes look brand new, so maybe over the years they extended the rang and created a 50V version. So OK let's go for that. So as sanity check, I decide to test teh voltage drop at full current, as indicated in the datasheet. It says that at 1A, it should drop 0.55V. Sounds about right for a Schottky at the current, so I am happy with that. So I put the diode across the lab supply terminals, using the current limit knob to slowly increase forward
current and watch voltage at the same time. Well guess what... at 1.0A, instead of 0.55V I get 2.2V !!!!     WHAT ?! I want my money back !!!  Does not make any sense... even for a "normal" diode 2.2V is silly high, not even plausible ! So I don't know what's going on.... factory rejects ? 


2)

" PHC 5V1 " ... couldn't find anything about that either. Looking more closely and Googling harder... looks like it should rather be read as " C5V1 PH ", and it would be  Philips equivalent for the BZX55C.
OK, so at least THIS ONE is really a Zener, that's a good start. So, I test them (I have x3 ) on a bread board with a 1k series resistor... increase the supply voltage slowly, watching for the 5V1 mark and....at 5V nothing happens... at 30V still nothing ! It behaves like a regular diode not a 5V1 Zener !  Diode failed open circuit ? Nope, all 3 test good, 0.7V drop. So neither shorted nor open circuit.
so they are counterfeit ? Or the factory made a mistake, they made regular rectifier diodes and mistakenly marked them as a Zener ?! 

Tough luck !

So be it those fake Zener and horrible Schottky... I guess only thing to do is put them all in the trash bin... 


02H10 going to bed..... 

[xrunner]

HOLD ON A MINUTE !!!! 

I wasn't 100% done with my mugs ...

Still more in boxes. 

[Specmaster]

@bd139 I just saw this flash up in my inbox and thought it would be of interest to you. You may already have seen it, but its better to be made aware of it twice than not at all   

https://www.eevblog.com/forum/testgear/abs-plastic-degradation-(brittle)-hp34401a-(circa-1992)/new/#new

[vk6zgo]

I’m going no car. Problem solved.

Ham spotted today with silly antenna 

What's silly about the antenna?

It is a perfectly good multi-element Yagi (I would guess for the "70cm" band), which the ham concerned is using in a portable setup.
It is not mounted on the car for mobile use, as that really would be silly!

There are many reasons why a ham might want to "go portable"----maybe no room at home for a reasonable antenna, or they may be participating in one of the ongoing competitions which are centred around various points of interest, like mountain/hill summits, lighthouses, National Parks, etc.

A ham might well think we are silly, with our obsession with finding, refurbishing & using elderly test equipment, or a fisherman silly, for standing on a beach in the middle of winter, brandishing a 15 foot fibreglass rod, with an expensive reel attached.

I've tried beach fishing, & it really is silly!!
I never learnt how to cast properly, the howling "Sou-Westers" would take the line & blow it back further down the beach, where the seagulls would fall upon the bait.

I lassoed a pelican once, when something similar happened at a river's mouth.

Sorry about the great slab of type, but it seems that the unthinking default reaction to hams on this forum has become a sneer.

Yes yes yes of course. Just to point out, I am was/am a ham (M0 full license) who has participated in SOTA . I know the drill. I know why. The whole thing is still very very silly but that's fine

However fishing is a just cruel unless you're going to actually eat the things so that's a poor analogy

I had every intention of eating the things, but beach fishing is something that seems to work for others, not me.

I have caught fish with a handline or short rod from a jetty, & eaten them (they were delicious!), but even there, waiting for a bite is a lot like sitting on 2m FM Simplex in VK6, & hoping for a contact---although my shack/lab/cat & dog room is slightly (not much) more comfortable than getting Jarrah splinters in my backside on a crappy old jetty!

The bloke in the original pic was probably going to make a bunch of contacts, if it is a good spot, or maybe a few from somewhere he can't get at home.
Again, sitting in a car, with a massive UHF antenna, & people thinking you're a weirdo, isn't my bag, but to each his own.

[cyclin_al]

I haven't seen any of those recently though, are they still used?

Yep in Boeing's and less so in them flying fiberglass Airbus things.

Carbon fiber not glass 
Then Boeing is just as carbon fiber (787) as the Airbus A350, even hit the market before the Airbus.

Then again carbon or aluminium makes no difference, as this refers to the airframe/cell only, which is not held together with safety wire to begin with... it's only used for the mechanical bits you graft onto the airframe. I bet 100 years ago with wood and fabric/clothe aircraft you had safety wires just as well ....

I may be very many pages behind, but could not resist on this one.

There is one airliner that is even more carbon fiber than the other carbon fibers.  Then again, it was designed by the french trying to be more french than the french.
Confused? 

The A220 was not designed by Airbus, but by the former group that now has split personality (after the A220 / C-Series project, they are now known as Airbus / Bombardier / deHavilland / Mitsubishi) in Quebec.

My apologies: trying to be more french than the french is getting as dangerously close to politics as I dare, which I will not go into.

I do agree that safety wires are more commonly found on older designs of aircraft (in the transport category), but also on smaller aircraft (ie. general aviation) where the technology has tended to lag.

[BU508A]

They sometimes just go bang when you turn them on. Usually when some ham has been inside them so med is fine because he's not a ham 

And now for something completely different. Poked the Z50 out of the window with the 250mm lens on it.



Need. More. Zoom. This could get expensive 

Jep!



 

[Saskia]

Friend of mine just built something like that.
He is coming over on Friday to convert me to the dark side.
Looking at some Vixen Schmid-Cassegrain or Maksutov and checking what he would accept in trade.

[Saskia]

Searching for a lost transformer out of one of my pinball machines (the T2 to be exact).
This is driving me nuts ... I may need someone's help to build a substitute. I do not want to junk that pinball ...

[Cubdriver]

The other recently ordered lead amputation apparatus arrived in the mailbox today.  As with the other one, verrah naace.



-Pat

[BU508A]

Searching for a lost transformer out of one of my pinball machines (the T2 to be exact).
This is driving me nuts ... I may need someone's help to build a substitute. I do not want to junk that pinball ...

How about a customer specific toroidal transformer?

https://www.die-wuestens.de/dindex.htm?/t2.htm
https://www.multi-circuit-boards.eu/preise/ringkerntrafos.html

They are not cheap, though.

[med6753]

Searching for a lost transformer out of one of my pinball machines (the T2 to be exact).
This is driving me nuts ... I may need someone's help to build a substitute. I do not want to junk that pinball ...

How about a customer specific toroidal transformer?

https://www.die-wuestens.de/dindex.htm?/t2.htm
https://www.multi-circuit-boards.eu/preise/ringkerntrafos.html

They are not cheap, though.

These guys do custom transformers too.

https://www.heyboertransformers.com/overview.shtml

[borjam]

Ooof, they are hovering around 60,000yen to 100,000yen second hand. Ouch.

Quite cheaper should be the JRC NRD-525. This older rig has some minor bugs: The audio is a bit muffled and it has quite some hiss. There were some mods available for those issues.

I got one two months ago. Really nice receiver, but make sure to grab a high serial number (40000+ or so).

The muffled sound is mostly a problem with the shitty internal loudspeaker. I have connected a cheap JBL monitor (104 BT) and it is a really different story. However, make sure to check the "line" output level in the receiver, it is usually too hot.

The worst problem with NRDs is the trimmer caps in the Loop1 card (the first PLL) which tend to age poorly.  The symptom is a completely deaf receiver in a frequency range (the tuning range is divided into four parts) and the "SQL" indication lit on the display.

[bd139]

They sometimes just go bang when you turn them on. Usually when some ham has been inside them so med is fine because he's not a ham 

And now for something completely different. Poked the Z50 out of the window with the 250mm lens on it.



Need. More. Zoom. This could get expensive 

Jep!



 

Actually I was looking at telescopes earlier with DSLR adapters 

Not much point in doing it in London though. Was lucky to get the moon!

[bd139]

Searching for a lost transformer out of one of my pinball machines (the T2 to be exact).
This is driving me nuts ... I may need someone's help to build a substitute. I do not want to junk that pinball ...

How about a customer specific toroidal transformer?

https://www.die-wuestens.de/dindex.htm?/t2.htm
https://www.multi-circuit-boards.eu/preise/ringkerntrafos.html

They are not cheap, though.

Also primary windings in the UK do custom transformers. Apparently they are quite reasonably priced too but that’s someone else’s opinion who owns a really big house in Surrey so YMMV 

https://primarywindings.com/design-service/

[bd139]

@bd139 I just saw this flash up in my inbox and thought it would be of interest to you. You may already have seen it, but its better to be made aware of it twice than not at all   

https://www.eevblog.com/forum/testgear/abs-plastic-degradation-(brittle)-hp34401a-(circa-1992)/new/#new

Interesting. Actually the handle is missing on mine so not a problem 

[bd139]

They sometimes just go bang when you turn them on. Usually when some ham has been inside them so med is fine because he's not a ham 

And now for something completely different. Poked the Z50 out of the window with the 250mm lens on it.



Need. More. Zoom. This could get expensive 

Back in my Pentax 35mm SLR days I used to have a 500mm f8 mirror (catadioptric) lens that I'd use with a 2x adaptor to make up an effective 1000mm f16 lens for astrophotography.

It was when using that I discovered that it was quite easy on a clear winter's night to get the silver oxide SR44 batteries in the camera cold enough that they'd stop working. (It's quite common when taking astrophotographs to let your camera and lenses cool down for a while before starting so they don't become the source of a heat haze of rising warm air.)

Yes can see how this degrades into another rabbit hole of zoomage  . I looked at the Nikon Z telephotos and they ain’t cheap. The top one is £13k!

I could see the haze through this trivial setup which was slightly annoying. Also the lens has a very effective image stabiliser in it but it drifts slightly so being mirrorless if you zoom in with the viewfinder you have to fight the stabiliser a bit to stay on the objective. If you turn the stabiliser off it’s even more difficult and it’d have to go on a tripod with a remote shutter and then, yep the moon is moving visibly so it’d keep buggering off.

I actually had an ancient Practika in the 90s that used mercury batteries. That was even worse because on a hot day the crappy LDR used for metering went intermittent. Ugh. Loved the camera though. That and Ilford 400 B&W out on a day out in London was great fun.

[Cubdriver]

Mugs:
 

-Pat

[ch_scr]

"Cup envy" (formerly only observed between girls) may now have been spotted in male participants of his thread 

[tggzzz]

They sometimes just go bang when you turn them on. Usually when some ham has been inside them so med is fine because he's not a ham 

And now for something completely different. Poked the Z50 out of the window with the 250mm lens on it.



Need. More. Zoom. This could get expensive 

OK. I'll save you some money, for TEA of course. All you need is, as with everything in life, some skill, planning, imagination, and luck.

From
https://apod.nasa.gov/apod/ap160201.html
https://apod.nasa.gov/apod/ap180328.html
https://apod.nasa.gov/apod/ap201002.html
https://apod.nasa.gov/apod/ap130130.html

[Henrik_V]

Searching for a lost transformer out of one of my pinball machines (the T2 to be exact).
This is driving me nuts ... I may need someone's help to build a substitute. I do not want to junk that pinball ...

How about posting some T2 data...  here or at https://www.eevblog.com/forum/buysellwanted/

[Vince]

HOLD ON A MINUTE !!!! 

But have also two that cause me trouble :

1)

" BYV 10 50 " ... looks all the world like a 10V Zener, tiny blue glass package, but can't find a datasheet for that. Plus, I tested it and it's not a 10V Zener... went up to 30Volts, what the lab supply allows.
So instead it looks like I might be mistaken and instead it's a not a Zener but more likely a BYV10-50 diode. BYV10 does exist, and it's a Schottky diode, 1Amp. DMM says yes it's likely to be right since they drop 0.165V. But...  the datasheets I can find say that a BYV10-50 does NOT exist. Only the 20/30/40 which represents the max reverse voltage. OK the datasheet is old and my diodes look brand new, so maybe over the years they extended the rang and created a 50V version. So OK let's go for that. So as sanity check, I decide to test teh voltage drop at full current, as indicated in the datasheet. It says that at 1A, it should drop 0.55V. Sounds about right for a Schottky at the current, so I am happy with that. So I put the diode across the lab supply terminals, using the current limit knob to slowly increase forward
current and watch voltage at the same time. Well guess what... at 1.0A, instead of 0.55V I get 2.2V !!!!     WHAT ?! I want my money back !!!  Does not make any sense... even for a "normal" diode 2.2V is silly high, not even plausible ! So I don't know what's going on.... factory rejects ? 

OK, that one is sussed out !
Had an idea while falling asleep in mly bed... now a new day has come and I can try out that idea...
The 2V reading was from the power supply's built-in voltmeter. So I thought maybe the two test leads I am using to connect the diode to the PSU, drop some voltage... 1A is not much, but those test leads are non-name crappy Ebay specials crocodile leads. They are really crap, borderline unusable because of the poor mechanical design/construction of the clips. They are very stiff to open, and next to zero grip / spring action when you release the jaws. So they can barely hold a wire or anything. Plus the hinge holding the two jaws together has so much play in it that when you press to open the jaws, they slide sideways relative to each other, in opposite directions. So you have to press with one hand, and with the other hand grad the tip of the jaws to try to keep them aligned while they open.
Very practical...
I also found a couple leads that were simply open circuit !! 

So all in all I thought, seeing how crap they are, and in order to draw a consistent picture, it would only be logical that they are also the kind of leads that use barely enough copper in them to allow for electrons to flow only one at a time ! 

So I redid my experiment of last night, and this time I measured voltage with a DMM directly across the diode and.... all is well !  At 1A it drops, well both diodes (have two of them), drop 0.59V for a nominal 0.55V according to the vintage datasheet !    So yeah... those crappy test leads, two 5Ocm ones hence 1meter total length, with only 1A.. Drop 1.5 Volt !!!! 

Cool, so I can add these two little Schottky to my collection 

2)

" PHC 5V1 " ... couldn't find anything about that either. Looking more closely and Googling harder... looks like it should rather be read as " C5V1 PH ", and it would be  Philips equivalent for the BZX55C.
OK, so at least THIS ONE is really a Zener, that's a good start. So, I test them (I have x3 ) on a bread board with a 1k series resistor... increase the supply voltage slowly, watching for the 5V1 mark and....at 5V nothing happens... at 30V still nothing ! It behaves like a regular diode not a 5V1 Zener !  Diode failed open circuit ? Nope, all 3 test good, 0.7V drop. So neither shorted nor open circuit.
so they are counterfeit ? Or the factory made a mistake, they made regular rectifier diodes and mistakenly marked them as a Zener ?! 

Have yet to come up with an idea to figure that one out... they simply don't behave like  5V1 Zener diodes, not much I can do about it 

[bd139]

OK. I'll save you some money, for TEA of course. All you need is, as with everything in life, some skill, planning, imagination, and luck.

From
https://apod.nasa.gov/apod/ap160201.html
https://apod.nasa.gov/apod/ap180328.html
https://apod.nasa.gov/apod/ap201002.html
https://apod.nasa.gov/apod/ap130130.html

...snipped images...

Thanks for this - quite inspiring actually  

[Vince]

I haven't seen any of those recently though, are they still used?

Yep in Boeing's and less so in them flying fiberglass Airbus things.

Carbon fiber not glass 
Then Boeing is just as carbon fiber (787) as the Airbus A350, even hit the market before the Airbus.

Then again carbon or aluminium makes no difference, as this refers to the airframe/cell only, which is not held together with safety wire to begin with... it's only used for the mechanical bits you graft onto the airframe. I bet 100 years ago with wood and fabric/clothe aircraft you had safety wires just as well ....

I may be very many pages behind, but could not resist on this one.

There is one airliner that is even more carbon fiber than the other carbon fibers.  Then again, it was designed by the french trying to be more french than the french.
Confused? 

The A220 was not designed by Airbus, but by the former group that now has split personality (after the A220 / C-Series project, they are now known as Airbus / Bombardier / deHavilland / Mitsubishi) in Quebec.

My apologies: trying to be more french than the french is getting as dangerously close to politics as I dare, which I will not go into.

Sorry you got it backwards ! 

Bombardier don't do carbon A/C, only Boeing / 787 and Airbus / A350.

The Bombardier is a traditional aluminium A/C with composites here and there where it's not too difficult to do... just like the A320 has been doing for 33 years now, or private jets as well.
When we say a carbon A/C we mean that the big technological jump has been made to make the two major parts of the A/C 100% carbon : the entire fuselage, pressurized is carbon, and the center wing box which basically holds the entire A/C together and bears all the loads, is also 100% carbon.

That is where the big, super expensive R&D and industrial/manufacturing jump lies. Grafting bits of CFRP here and there to reduce weight is nothing new or special... been done for decades now. Full fuselage and CWB are the real deal.

Will Bombardier make the big switch to carbon one day ? Now that Airbus bought them, and if they intend to keep the brand under their wing in the long term (I think they are), then in order to protect their investment and ensure the long term commercial success of the ex C series / A220, they will have no choice but eventually cough the cash to R&D it to full carbon. Gonna cost a pretty penny to R&D, but it's the next logical step, it needs to be done. Luckily now that Airbus has the experience of the A350, it should be a bit easier and quicker/cheaper to apply that knowledge and experience to another A/C type. It's known territory for Airbus now.