Test Equipment Anonymous (TEA) group therapy thread

[BU508A]

So no I don't remember them as being obsessed about opening doors to the point of trying all day long to improve their techniques, nor do I remember any of them going through the trouble of getting a toolbox and circular saw from the garage either...

Why should they? They have claws. And while they won't succeed in getting through the doorblade, they can use them to make enough of a racket to get what (or rather where) they want.

Especially when they know there's some warm and cozy hollow-state electronics on the other side.

Could you post this picture here?
https://www.eevblog.com/forum/chat/post-a-picture-of-a-cat!/

 

Thanks.

[PA0PBZ]

Oh and also picked up an Agilent SA (on gumtree of all places) and a HP cup also.

I have a key generator for the options and since it's out of support not afraid to use it
PM me the ID and what options you want.

Thanks, but I think all the options are already installed;
506-Frequancy Range 100K-6GHz
P06-Preamplifier 6GHz
TG6-Tracking Generator 6GHz
N8995a-SR6- Stimulus Response Measurement
271-Spectrogram
AFM-AM/FM Tune&Listen
N8996a-1FP-AM/FM Modulation Analyser

Not aware of any other options.

Yes, looks like you are all set!

[Cerebus]

Cerebrus will sure give me the correct number, but IIRC cats and related mammals spend like 80% of their time sleeping anyway... remaining 20% for eating fighting and fucking.

[Looks at cardboard box full of sparked out cat.]  I'd say 80% was an underestimate.

Whatever the figure the balance is not mostly spent on fighting and fucking. A partial list of actual occupations for the balance would be:

• Being on the wrong side of a door, being let through it, and then still being on the wrong side of a door and wanting to go back
• Refusing to eat food that yesterday was the only thing you wouldn't refuse to eat
• Picking the most inconvenient time to climb into someone's lap and going to sleep
• Refusing to climb into someone's lap when they actually want a cat in it
• Sitting on dustbins
• Judging
• Staring critically at people
• Being the tallest person in the room by climbing to somewhere inaccessible, by a route that either explicitly forbidden or will cause the greatest amount of chaos
• Despite being the lightest person in the household, making the most noise thumping up and down the stairs
• Acrobatic entomology
• Taking up as much room on the sofa as two human beings, between two human beings on a two seat sofa
• Getting into the one room in the house that you are forbidden from being in
• Coming in via climbing to a upstairs window. but insisting that you are let out via a downstairs door
• Enjoying the sound of creaking arthritic human knees as they walk down stairs for the sole purpose of letting you out
• Going out via an open upstairs window when you're supposed to be staying in
• Going around all the neighbours in turn and insisting that your staff haven't fed you for a month
• Conducting staff appraisals
• Waking the staff up 30 minutes before their appointed start time for the day by scratching at their bedroom door
• Requiring staff to always accompany you to meals just in case your bowl that you observed being filled 5 minutes ago has magically emptied itself in the meantime

Very much a partial list.

[cyclin_al]

Boy I thought the may subject was your first tub scope, I must have been wrong !

   I guess some of us are like cats, getting distracted by whatever is shiny and ... ooh new topic in the thread.

I looked up some information on the RM564.  In theory, this one is all tubes.  The RM564B is the later solid state version.

I like the form factor and overall size to fit into a rack.
For comparison, a RM585 is a huge monster.

Tekwiki indicates that the plug-ins drive the deflection plates directly. I noted that means calibrating/adjusting each plug-in for the scope.
However, is the driver circuitry something to bang my head on over and over with each plug-in?
I assume if the driver circuitry is on the mainframe like in other Tek families, then it only has to be dealt with once.

There are no cool alternate phosphor colours for the CRT, just the possibility of one with a faster writing rate.

[mansaxel]

the first owner carved his initials in the front case

People who write on TE plastic with something sharp should be sent to Tehran to get their hands cut off.

That said nice score! The 87V is a must!

Indeed a nice score, but if you have the MetraHit 25 (or the -hp- 974a; I have both!) the 87V IMNSHO is strictly optional, something which the Case Containing Trio Of Probulators^(tm) with attached 27CE is not, also IMNSHO.

 

Edit: And the 27CE with probes is mandatory for you, Papa Smurf!

[PA0PBZ]

Very much a partial list.

I'd like to add:

 - Demanding to be let outside at the back door, then realize it's raining and repeat the process at the front door.

[Neper]

And, most prominently, sitting in the absolute centre of interest in the room, e.g. on the book or newspaper that's being read, on the computer keyboard or smack in front of the monitor.

[med6753]

Cerebrus will sure give me the correct number, but IIRC cats and related mammals spend like 80% of their time sleeping anyway... remaining 20% for eating fighting and fucking.

[Looks at cardboard box full of sparked out cat.]  I'd say 80% was an underestimate.

Whatever the figure the balance is not mostly spent on fighting and fucking. A partial list of actual occupations for the balance would be:

• Being on the wrong side of a door, being let through it, and then still being on the wrong side of a door and wanting to go back
• Refusing to eat food that yesterday was the only thing you wouldn't refuse to eat
• Picking the most inconvenient time to climb into someone's lap and going to sleep
• Refusing to climb into someone's lap when they actually want a cat in it
• Sitting on dustbins
• Judging
• Staring critically at people
• Being the tallest person in the room by climbing to somewhere inaccessible, by a route that either explicitly forbidden or will cause the greatest amount of chaos
• Despite being the lightest person in the household, making the most noise thumping up and down the stairs
• Acrobatic entomology
• Taking up as much room on the sofa as two human beings, between two human beings on a two seat sofa
• Getting into the one room in the house that you are forbidden from being in
• Coming in via climbing to a upstairs window. but insisting that you are let out via a downstairs door
• Enjoying the sound of creaking arthritic human knees as they walk down stairs for the sole purpose of letting you out
• Going out via an open upstairs window when you're supposed to be staying in
• Going around all the neighbours in turn and insisting that your staff haven't fed you for a month
• Conducting staff appraisals
• Waking the staff up 30 minutes before their appointed start time for the day by scratching at their bedroom door
• Requiring staff to always accompany you to meals just in case your bowl that you observed being filled 5 minutes ago has magically emptied itself in the meantime

Very much a partial list.

You forgot one. Getting hairballs and puking on the carpet for you to not see and step in. 

[mnementh]

On The Bench Today: Building Puck Light Assemblies

Putting up some puck lights under the cabinets; got these cheap off Amazon. As I want them to be as unobtrusive as possible, I decided to solder them in daisy-chain prior to installation. This means, of course, that I had to figure out exactly how they are going to be spaced beforehand.

These draw ~200mA per; that means I should be able to chain 3-4 before voltage drop across the 24ga wires becomes a real issue.

mnem
*lit*

[mansaxel]

Very much a partial list.

All of it very true. Our cat, a boy of 16 years, still looks like a 2-year old, despite being neutered and all. He's got some arthritis in his rear legs, but we're successfully treating it with Extra Expensive Cat Fud which he actually likes.  We all know he's on borrowed time, what with him being an outdoor cat and all. We've had to take him to the vet 4 times during these years; one was him getting neutered, so three visits in all.

[med6753]

Tekwiki indicates that the plug-ins drive the deflection plates directly. I noted that means calibrating/adjusting each plug-in for the scope.
However, is the driver circuitry something to bang my head on over and over with each plug-in?
I assume if the driver circuitry is on the mainframe like in other Tek families, then it only has to be dealt with once.

There are no cool alternate phosphor colours for the CRT, just the possibility of one with a faster writing rate.

Correct, on the 560 series the plug-in's drive the CRT deflection plates directly. But once a plug-in is working properly the only adjustment that might be required is a tweak of the gain on a vertical plug-in and the sweep cal on a time base plug-in. The pots are right on the front panel of the plug-in.

On 500 series the vertical and time base plug-in's are essentially "pre-amps" to the vertical and time base (horizontal) circuits contained within the mainframe. Same with newer 5000 and 7000 series.

[Cubdriver]

Cats poking at the electronics?  Unheard of.  I don't know what you're talking about...

















Nothing of that sort EVER happens here!

-Pat

[mnementh]

Yeah... that's actually why I prefer it. Red LED displays are just a fuzzy blob at 2m to me without my glasses; even larger ones than this. This one I can actually read.

I assume it's to do with the whole rods vs cones vs light wavelength thing; doesn't matter. Blue LEDs are the clearest to me. OTOH, I've long had issues with seeing in low light... or even "normal" light.

That is unusual.
Most people have trouble focusing on blue light sources due to fluorescence in the structures of the eye.

Anybody who has been to an optician and has been refracted (as the opticians call it) will be familiar with being asked to look at identical black figures side by side, one on a red background, one on a green = "Which is clearer? Red or green?". Know as a duochrome in the trade. One something this (there are lots of variants):



The reason that they do this is to ensure that they get things properly in focus for us at wavelengths roughly halfway between those two colours. The green will focus slightly in front of the retina, the red slightly behind, and yellow, if it was there, would fall smack on the retina. Like this:   

The quantitative difference in focus for red and green is about 0.5 dioptres.

The eye has surprisingly high dispersion depending on wavelength, our eyes have pretty bad chromatic aberration. We don't normally perceive it because of all the post-processing our brains do - it will take information from all colours and just fill in the gaps. The eye naturally focuses in the yellow and that is why black on yellow looks crispest to us - a good reason why all those serious warning signs are in black and yellow.

Looking at the focus diagram above again it's pretty clear that the focus for blue falls even further in front of the retina. In effect everybody is shortsighted in blue. If all you've got to work with is blue light you are going to both have and perceive a fuzzy image because there isn't enough information for your brain to fill in the gaps.

If mnem is longsighted that would be an explanation why he can see blue better than red without his glasses. If he isn't but is shortsighted then the fact that he perceives blue better than red without his glasses is just more proof of what we've all known all along - that he is weird.

Thanks for the infodump.  I remember some of this from my discussions with my optometrists over the years.

  again. No fair on that duochrome... it's a fuzzy jpg in and of itself; can't be read even zoomed in.

Definitely very nearsighted; have been since toddlerhood and got my first glasses at 6. At arm's length, my fingers are aught but big pink sausages. Or bronze with black claws, depending on whether I'm using my mind's eye or those in my head.

mnem
 

[Cubdriver]

Cerebrus will sure give me the correct number, but IIRC cats and related mammals spend like 80% of their time sleeping anyway... remaining 20% for eating fighting and fucking.

[Looks at cardboard box full of sparked out cat.]  I'd say 80% was an underestimate.

Whatever the figure the balance is not mostly spent on fighting and fucking. A partial list of actual occupations for the balance would be:

• Being on the wrong side of a door, being let through it, and then still being on the wrong side of a door and wanting to go back
• Refusing to eat food that yesterday was the only thing you wouldn't refuse to eat
• Picking the most inconvenient time to climb into someone's lap and going to sleep
• Refusing to climb into someone's lap when they actually want a cat in it
• Sitting on dustbins
• Judging
• Staring critically at people
• Being the tallest person in the room by climbing to somewhere inaccessible, by a route that either explicitly forbidden or will cause the greatest amount of chaos
• Despite being the lightest person in the household, making the most noise thumping up and down the stairs
• Acrobatic entomology
• Taking up as much room on the sofa as two human beings, between two human beings on a two seat sofa
• Getting into the one room in the house that you are forbidden from being in
• Coming in via climbing to a upstairs window. but insisting that you are let out via a downstairs door
• Enjoying the sound of creaking arthritic human knees as they walk down stairs for the sole purpose of letting you out
• Going out via an open upstairs window when you're supposed to be staying in
• Going around all the neighbours in turn and insisting that your staff haven't fed you for a month
• Conducting staff appraisals
• Waking the staff up 30 minutes before their appointed start time for the day by scratching at their bedroom door
• Requiring staff to always accompany you to meals just in case your bowl that you observed being filled 5 minutes ago has magically emptied itself in the meantime

Very much a partial list.

That one is definitely spot on!  Nothing like an airborne insect to focus feline attention.

[med6753]

I like cats and I wish I could have at least one but landlord sez no bueno to pets of any sort. I even asked once if I could get a parakeet and the answer was still no bueno.

His rationale was that if someone gets a pet of any sort then some dumbass would want a big ass dog unsuitable for an apartment and use that as a justification. I get it. 

[mnementh]

Very much a partial list.

I'd like to add:

 - Demanding to be let outside at the back door, then realize it's raining and repeat the process at the front door.

Also add:

- Tear-assing through the house one after another, and waking you up in the middle of the night by stepping on your tongue...!

Yes, and when you think aboot it, and the horrors of toxoplasmosis (including a particularly nasty form of encephalitis), it's even worse.   

also, cats are solar powered.

mnem
and no, that is not some pervy joke aboot where a dwagon's tongue might be in the middle of the night.   

[Cubdriver]

I like cats and I wish I could have at least one but landlord sez no bueno to pets of any sort. I even asked once if I could get a parakeet and the answer was still no bueno.

That's a bummer.

His rationale was that if someone gets a pet of any sort then some dumbass would want a big ass dog unsuitable for an apartment and use that as a justification. I get it.

And idiots like that are why we can't have nice things.  Some jackass has to push the envelope too far, and the easiest thing for those in control to do is simply say no to everything to shut down arguments and whining.

-Pat

[mnementh]

I am doomed: I have started migrating my workbench stuffs from my oak desk in the living room down to the basement.

I may never see the light of day again.

mnem
 

[med6753]

It's still sitting there spread out across the bench. Tied up with domestic chores like laundry and probably won't get to it today. Tomorrow doesn't look promising either. I did prepare a BOM for replacement of the beaded tants and that little sucker has 19 of them. No electrolytics even in the PSU. 



And I have a riddle and looking for possible theories. I have my own which I'll detail. Yesterday while I was adjusting the Type 1A2 plug-in the sweep mag on the Type 547 on a fairly regular basis would go nuts for a while then return to normal. And carefully note...during this time the Type 547 was laying on it's side to access the plug-in controls.

Once I completed the cal and compensation put the Type 547 back upright. Decided to start the burn-in process. From yesterday afternoon through this morning the scope has performed flawlessly. It's gone through almost 8 hours of burn-in with multiple power cycles. NOT ONCE did the sweep mag act up. Not even a tiny twitch.

So what is going on? My theory. The 2 horizontal output tubes (6DJ8) with the scope upright are installed up side down. Typically tubes are installed upright but there's usually no restriction on mounting position. I suspect over the past 45 years or so gravity has been pulling ever so slightly on those elements and loosening them. And when the scope is moved from it's upright position we are getting some mircophonics which is causing the sweep frequency to change. I guess I could test this by swapping out the 6DJ8's. I have a bunch of them which would give an audiophool a hell of a wet dream.  Sound plausible?   

[Cubdriver]

Very much a partial list.

I'd like to add:

 - Demanding to be let outside at the back door, then realize it's raining and repeat the process at the front door.

Petronius the Arbiter in Heinlein's 'The Door into Summer'  Heinlein: When we were living in Colorado there was snowfall. Our cat — I'm a cat man — wanted to get out of the house so I opened a door for him but he wouldn't leave. Just kept on crying. He'd seen snow before and I couldn't understand it. I kept opening other doors for him and he still wouldn't leave. Then Ginny said, 'Oh, he's looking for a door into summer.' I threw up my hands, told her not to say another word, and wrote the novel The Door Into Summer in 13 days.

Also add:

- Tear-assing through the house one after another, and waking you up in the middle of the night by stepping on your tongue...!

Yes, and when you think aboot it, and the horrors of toxoplasmosis (including a particularly nasty form of encephalitis), it's even worse.   

mnem
also, cats are solar powered.

LOL - I' can't say I've ever had THAT issue (to the best of my knowledge my tongue stays inside my mouth while I'm sleeping), but Nixie did actually wake me in the wee hours this morning when he flopped down and curled up with his back against my face, blocking my nose.

-Pat

[bd139]

Ugh all that cat hair in that test gear. Yuck 

Out of action for a few days. Managed to end up with an extra hat at work for a bit  .

There is no time for TE 

[Robert763]

Our "new" dog likes to stick her wet nose in everything - literally.
A couple of weeks ago I was using a Dewalt power saw and sure eough she suck her nose against the edge of the blade when it was running 
No I'm not stupid or cruel, it was a vibratory saw  . So no injury but she won't do that again.

[25 CPS]

Sounds you need to take the lab on the rails. We've got a pretty extensive streetcar operation downtown that is partially run by a commercial branch of the Historical Streetcar Society. You can end up in a 1911 streetcar for your work commute, or in a very modern one , a bit depending on what they feel like running. 

Edit: Better english.

Yes, that's the plan although the pandemic's thrown a bunch of delays and inconveniences up.  That's actually the reason why I've built out my set of portable test equipment the way I did.  Between "I say all you need is a laptop" work where one of the managers actually said that a couple of weeks ago where I keep getting kneecapped by no decent test equipment, side jobs, and railway museum volunteering, a fairly comprehensive set of portable equipment in the truck became necessary over the last few years.

I'm not sure if you remember the post I did when I got a Fluke Scopemeter from a pawn shop for downright reasonable money compared to the cost of purchasing a new one?



One of the reasons was an incident at work where I wasted more time finding a working oscilloscope and then a set of probes that hadn't been damaged than I did investigating the actual problem, but also because streetcars are barely a CATIII environment.

Plus, I've had enough times where I've been underneath one watching controller sequences where I've been crossing my fingers and standing as far away as I can saying, "Please don't blow up in my face.  Please don't blow up in my face.  Please don't blow up in my face." as power is applied.  600 VDC at potentially well over 300 A can go wrong spectacularly and makes even the biggest vacuum tube amplifier I've ever had on my bench at home look small.

Given this, I'm still surprised some people here took issue with me opening up my wallet and spending real, albeit far less than retail, money on that Fluke vs. buying a cheapo Chinese scope.  If I'm going to have a streetcar controller potentially go bad during a test, I don't need to draw it down a set of test leads and have the instrument explode in my hands.  I know we're all into getting the best deals here and I was happy to get a great deal on the Scopemeter even if it was still expensive, but this really isn't a use case where the cheapest tablet scope of the day on Aliexpress is a good choice.

[Cubdriver]

It's still sitting there spread out across the bench. Tied up with domestic chores like laundry and probably won't get to it today. Tomorrow doesn't look promising either. I did prepare a BOM for replacement of the beaded tants and that little sucker has 19 of them. No electrolytics even in the PSU. 



And I have a riddle and looking for possible theories. I have my own which I'll detail. Yesterday while I was adjusting the Type 1A2 plug-in the sweep mag on the Type 547 on a fairly regular basis would go nuts for a while then return to normal. And carefully note...during this time the Type 547 was laying on it's side to access the plug-in controls.

Once I completed the cal and compensation put the Type 547 back upright. Decided to start the burn-in process. From yesterday afternoon through this morning the scope has performed flawlessly. It's gone through almost 8 hours of burn-in with multiple power cycles. NOT ONCE did the sweep mag act up. Not even a tiny twitch.

So what is going on? My theory. The 2 horizontal output tubes (6DJ8) with the scope upright are installed up side down. Typically tubes are installed upright but there's usually no restriction on mounting position. I suspect over the past 45 years or so gravity has been pulling ever so slightly on those elements and loosening them. And when the scope is moved from it's upright position we are getting some mircophonics which is causing the sweep frequency to change. I guess I could test this by swapping out the 6DJ8's. I have a bunch of them which would give an audiophool a hell of a wet dream.  Sound plausible?

It's possible.  I'd suggest gently tapping the suspect tubes with a pencil or something similar (hard enough to give them a bit of a shock, but obviously not so as to to break them) while observing to see if anything happens when doing so.  And keep that stash of 6DJ8s quite - the audiophools like them nearly as much as 12AX7s.

-Pat

[Neper]

The 2 horizontal output tubes (6DJ8) with the scope upright are installed up side down. Typically tubes are installed upright but there's usually no restriction on mounting position.

Not quite. Upright or upside down is usually ok, but some tubes don't like working on the side because of irregular heating or heated elements sagging. It's a known fact that some power tubes with rather long filaments don't like to be put on their side. I seem to remember that one type of power tube was designed especially for sideways operation by modifying its filament.

Another reason might be heat from the tube hitting other components in this position.