Test Equipment Anonymous (TEA) group therapy thread

[cyclin_al]

I guess that makes me a fully accepted member now.

Junior member. You'll have to be able to rack up more than 3 digits of precision for full membership. 

And only a 150mm full scale? Really? My commiserations. 

Oh come on, he got the same calipers as I have ... the cheapies from Princess Auto 
Oh wait, that makes me a junior member too ... 

[cyclin_al]

Am currently bothered by a slightly leaking 3/4" cast iron union coupling in my computer cooling system. It did not leak before, but I had to break it open to fix a broken safety valve. Now, on reassembly, it leaks.

The traditional British plumber's answer to that is to pack the joint with sisal fibre and something called "Plumber's Mate" which, by inspection, seems to be a putty of clay and linseed oil similar to glazier's putty.

The more modern ones use PTFE tape

Up in the great white north, the tapered thread for water plumbing is known as NPT (national pipe thread).  We have to watch out as there are numerous other threads for gas, pneumatics and other applications.  Regular plumbers use the teflon (PTFE)  tape as you said.  Pneumatics for air compressors and the like also use the teflon tape.  Gas fitters use a paste that they call "pipe dope".

However, both the well frackers and the well pump specialists used both the teflon tape and the plumbing paste together.  They better get it correct the first time since it is a nasty job, and I cannot afford to pay for a second time around.  I watched them very carefully on their recent visit.

The plumbing paste used over here has a consistency that is more like anti-sieze compound.  The paste does have PTFE in it.  It is also called "pipe dope", but is definitely not the same as what the gas fitters used.  Are we confused yet?   
Putty like you described is not used here for actual plumbing or anything critical.  Rather, the putty is used for things like forming a gasket between the sink and counter top to prevent drips of water getting into the cupboards.

Yes, I fear to touch plumbing that is not leaking.  I have no issues with taking on plumbing that is leaking ...

[beanflying]

I guess that makes me a fully accepted member now.

Junior member. You'll have to be able to rack up more than 3 digits of precision for full membership. 

And only a 150mm full scale? Really? My commiserations. 

I've only got three sets of calipers, not counting brake ones. One plastic, perhaps accurate to 1mm. One Chinese, OK to 0,2mm. And one vintage Swedish, which is the one I trust. And a no-name micrometer.  I bought a NOS Mitutoyo caliper set for the wife. I thought she deserved them.

All are fully mechanical.

I do not bother too much about juniority or not. Am happy that I have no complicated mechanical measurements to make. 

Am currently bothered by a slightly leaking 3/4" cast iron union coupling in my computer cooling system. It did not leak before, but I had to break it open to fix a broken safety valve. Now, on reassembly, it leaks.

With Cast Unions scrap it and put in a Brass one, Iron unions were always a pain to reseat after time. However before that first thing is check the alignment of the pipes in and out or even try rotating one side of the union and see if it helps/stops the weeping. Definitely don't try tape on the Union threads either they are not designed to seal it is the flat faces that do the sealing. In theory you could lap the faces but I wouldn't bother.

As to Calipers and buying the equivalent of an 8 1/2 digit Bench MM while 3 or 4 1/2 will get it done for daily use I know where my $ are going.

Must look up new memory for my 3458A because it is essential for increased .........

[med6753]

I guess that makes me a fully accepted member now.

Junior member. You'll have to be able to rack up more than 3 digits of precision for full membership. 

And only a 150mm full scale? Really? My commiserations. 

 

Oh come on, he got the same calipers as I have ... the cheapies from Princess Auto 
Oh wait, that makes me a junior member too ... 

I know. These damn Engineers. Bunch of stuck ups. 

At least we don't have to wear their uniform. 

[beanflying]

I guess that makes me a fully accepted member now.

Junior member. You'll have to be able to rack up more than 3 digits of precision for full membership. 

And only a 150mm full scale? Really? My commiserations. 

 

Oh come on, he got the same calipers as I have ... the cheapies from Princess Auto 
Oh wait, that makes me a junior member too ... 

I know. These damn Engineers. Bunch of stuck ups. 

At least we don't have to wear their uniform. 

Stop looking at my old farcebook photos 

My pocket protector ran out of room so I laser cut one and another thing of the to do list   

[Brumby]

Proudly pocket protector free zone here!

[VK5RC]

I actually use a pocket protector daily as they are just what I need. A lot of my work is mobile with nothing more than I can stick in pockets of office type clothing. Billing information is typically collected in the form of a 'sticky label' still attached to its backing - about 6x3cm. Putting them inside the pocket protector (in pants rear pocket) stops the paper and print from 'disappearing' . Helped my billing by thousands $ over the years 👍

[Specmaster]

I guess that makes me a fully accepted member now.

Junior member. You'll have to be able to rack up more than 3 digits of precision for full membership. 

And only a 150mm full scale? Really? My commiserations. 

 

Oh come on, he got the same calipers as I have ... the cheapies from Princess Auto 
Oh wait, that makes me a junior member too ... 

I know. These damn Engineers. Bunch of stuck ups. 

At least we don't have to wear their uniform. 

That must be an American type thing then, I've never come across anyone that looks like that regardless of their engineer status, dickie bow's died a death years ago and the pocket protector  , the nearest to those I've seen is that some of the more academic engineers were leather elbow protectors on the sleeves of their jackets.   

[McBryce]

It has become very apparent that in order to gain full acceptance into this elite group that I must have at least one set of calipers in my toolbox. So I bought one. But I'm not quite sure what I'm going to do with it. It's heavy and unwieldy. Perhaps use it as a paperweight? 

You know that if you paint them bright red the car goes faster (or at least all those would be tuners seem to think so).

McBryce.

[med6753]

You know that if you paint them bright red the car goes faster (or at least all those would be tuners seem to think so).

McBryce.

And if it says "Brembo" on them it's even faster.

[URI]

I guess that makes me a fully accepted member now.

Junior member. You'll have to be able to rack up more than 3 digits of precision for full membership. 

And only a 150mm full scale? Really? My commiserations. 

 

Oh come on, he got the same calipers as I have ... the cheapies from Princess Auto 
Oh wait, that makes me a junior member too ... 

I know. These damn Engineers. Bunch of stuck ups. 

At least we don't have to wear their uniform. 

That must be an American type thing then, I've never come across anyone that looks like that regardless of their engineer status, dickie bow's died a death years ago and the pocket protector  , the nearest to those I've seen is that some of the more academic engineers were leather elbow protectors on the sleeves of their jackets. 

Yep and it's is larger than life, a caricature.

Nevertheless I actually had a co-student (yes I'm an TU Dipl.-Ing.  ) at university who literally didn't know were to hold the soldering iron but wore suit and tie as a student(!)   
Almost all others were clothed in T-shirts and wore-out jeans or something like that.
-Ok that was a student of the combined study of electrical engineering and business administration -those were known for deselecting the electrical engineering related courses after reaching bachelor grade.   

[Saskia]

You know that if you paint them bright red the car goes faster (or at least all those would be tuners seem to think so).

McBryce.

And if it says "Brembo" on them it's even faster.

Bullshit.
You need one of those.

[URI]

I just announced having bought several power supplies for calibrating my HP 6060B and 6063B electronic loads:
https://www.eevblog.com/forum/index.php?topic=47932.msg3578713#msg3578713

For the 6063B I still need a regulated 240/2A supply. 

OTOH I managed to get into python programming.
Ok, I had to:
The calibration of these electronic loads is only possible by programming the load over GPIB. In the operation manual there's a rudimentary calibration skript written in Agilent BASIC.
It's rudimentary in a sense that it doesn't have any checks for inputs or errors.   
Ported that script to python 3 and added those checks. Testing of my script without saving the calibration data was successful so far. 

Now waiting anxiously for those supplies to arrive. And I'm still looking for a cheap 240V/2A regulated power supply.

[Robert763]

You know that if you paint them bright red the car goes faster (or at least all those would be tuners seem to think so).

McBryce.

And if it says "Brembo" on them it's even faster.

Bullshit.
You need one of those.

And one of these to launch it 

[BU508A]

I'm really curious how this will turn out¹.




¹And it is caliper-related. Somehow. 

[Robert763]

On calipers,
I was using mine today. The Efratom FRK oscillator project is progressing slowly. I was looking at the mounting screws. They need to be longer because there is now the rear panel of the case between the oscillator and heatsink. The screws are pretty small. I looked at the manual and there is a defect right through the screw size. It looks like 2.6mm which is a bit of an odd size. I then looke at the Racal standard the uses the FRK. It calls up M2.5. So I measured the screws in the unit that are probably original. They are clearly M2.5 (mjor dia 2.380 to 2.480) not M2.6 (2.480 to 2.980). However they are loose in the tapped holes in the unit.
Both M2.5 and M2.6 are 0.45mm pitch as standard (0.35 option) so I've ordered some M2.6 cap heads. Usefully they are used on some model helicopters so are available.
I have several sets of calipers from cheap innacurate digital ones just used fror marking out through to 12" Mitutoyo and micromoters, height gauges and slip gauges. The calipers in the photo are my everyday mid-range ones from ARC Eurotrade  costing about £25 Highly recommended, They even do imperial fractions.
https://www.arceurotrade.co.uk/Catalogue/Measurement/Calipers/Digital-Calipers-150mm-300mm-6-12

[Vince]

[HP 120B scope]

Very nice  , one of the few common round CRT hp scopes I haven't got in my collection, have the 130A & 130C, many 140 series, a couple of 175A and two versions of the hardest to find the 150A/AR.

That's my luck eh ?! My very first HP scope bought by accident turns out to be one that even an avid collector like you somehow doesn't yet have ?! 
Maybe it's because it's common as you say, so you didn't try that hard to get one ? You focused on the rare ones...

Only have one classic Tek here, the dual beam 502A.

So we are complementary then !    HP fan with one Tek up in the UK, and the other way around in Frog land.

That packaging was terrible, you were very very lucky not to end up with the cast front handles snapped off.  Really needed to spend a bit more on a bigger box and 2-3 inches of protection all around.

Yes I consider myself very lucky indeed. However I never expected to have a top notch packaging, seeing as the guy gave it away, did not have a single penny from the "sale"...how could I expect him to PAY to get proper materials to package the thing well. giving it for free was already nice enough, but asking him to lose money in the process uh... not happening in this world. I should have offered to send him a few Euros to buy some polystyrene and large enough card board boxes, but didn't think of it, and he didn't ask either...
So let's just rejoice that it arrived intact ! 

If you haven't seen this then have a look, it's some history from the designer that worked on the 120B;

Thanks fr the links, was a great read ! 
It's my first HP piece of gear so I know absolutely no internet "places" to leanr about the history of the brand, all the models, their specs, forums to get help and knowledge etc... I have zero connection to the HP world. Now I have you, and this website, it's a start, should do it for this lone scope I think ! 

Think it's a bit harsh calling 450kHz bandwidth "abysmal", it was intended as a lower cost & spec oscilloscope and something Tek didn't have in their line-up at the time, the article above suggests these low cost scopes sold reasonably well.

Hey I was just being sarcastic, you are on TEA you know !   

And I have to disagree on your thoughts about the knobs/jacks looking & feeling cheap. 

I didn't mean to trigger you ! 

OK, will wait 'til I refurbish the scope to give my final judgment on those knobs... maybe with a thorough cleaning and a a bit of buffing, they will come up much nicer...


Anyway... I couldn't help. I decided to pick the missing tubes in my old Teks to try and fire up the HP 120B.... but ran into troubles after just 5 minutes.

The 3 missing 6U8.. according to my little spreadsheet where I collected, from the part manuals, what scope contains what tubes and in what quantity.... it appeared that the 6U8 were present, somehow, in only ONE scope : the type 515A. And only has 3 of them, which is exactly how many I need for the HP scope so..
So, I just pulled one of my 515A, the one I am willing to "sacrifice", installed it on the bench, removed both side panels, and looked at all the tubes, searching for the 6U8 tubes and.... found NONE AT ALL !!!!  Eh ?!!! 

So I am in trouble, will need to BUY them, no, that was not planned...

So, I checked the parts list in the manual, to see where I goofed up, because surely I did, somewhere... and it appears that the 6U8 ARE listed... but only for  EARLY units ! So I guess my unit is not old enough... though I can't tell because I can't make sens of the SN numbering system on these old Teks, often.

HOWEVER..... it says that newer units replaced the 6U8 with.... with ..... a 6AU6 !!   Have TONS of them in my Teks scopes, tons of them !
So... maybe I can substitute the 6U8 with  6AU6's ? That's assuming that did not require modifications to the surrounding passive components, resistor values etc... I guess I could check for that too, to feel better...

Welcoming any thoughts on the matter !!! 

UPDATE :  Oh oh... no, not that simple.  Parts list says that one of the 6U8 was replaced by a 6AU6, but the other two 6U8 were replaced with 6DJ8's !   So I guess it's more complex than meets th eye and I should order actual 6U8 tubes ?   So much for my cheap and quick power up... postponed then 

[SeanB]

Bet Lock Picking Lawyer will have it open in under 2 minutes, and just to be sure it was not a fluke, lock and unlock it again in under another minute, while saying it compares favourably to the Masterlock.

And yes i do have a few sets of vernier calipers, the usual 150mm ones, plus a slightly bigger 660mm one. Helios Germany, i got it for free, because my BIL bought it on auction for almost nothing, he wanted the wooden box it came in. What is a Civil engineer going to do with a vernier micrometer, his standard measuring tool is a dumpy level and a rod, along with a tape measure and a rolling wheel. Yes we did use a dumpy level to install a gate rail, 1cm fall on it for drainage.

[mnementh]

moo.

Looking for my big red box of o-rings, that I might mod these RC cars with oil-damped shocks. grr.

mnem
and I'll probably use my cheap0 Chinese calipers to measure 'em.

[Cerebus]

On calipers,
I was using mine today. The Efratom FRK oscillator project is progressing slowly. I was looking at the mounting screws. They need to be longer because there is now the rear panel of the case between the oscillator and heatsink. The screws are pretty small. I looked at the manual and there is a defect right through the screw size. It looks like 2.6mm which is a bit of an odd size. I then looke at the Racal standard the uses the FRK. It calls up M2.5. So I measured the screws in the unit that are probably original. They are clearly M2.5 (mjor dia 2.380 to 2.480) not M2.6 (2.480 to 2.980). However they are loose in the tapped holes in the unit.
Both M2.5 and M2.6 are 0.45mm pitch as standard (0.35 option) so I've ordered some M2.6 cap heads. Usefully they are used on some model helicopters so are available.
I have several sets of calipers from cheap innacurate digital ones just used fror marking out through to 12" Mitutoyo and micromoters, height gauges and slip gauges. The calipers in the photo are my everyday mid-range ones from ARC Eurotrade  costing about £25 Highly recommended, They even do imperial fractions.
https://www.arceurotrade.co.uk/Catalogue/Measurement/Calipers/Digital-Calipers-150mm-300mm-6-12

M2.5 is a "preferred size", M2.6 is not. The next up preferred size is M3.0. Why, oh why, would someone pick M2.6 as a size? In terms of any property a screw needs (UTS, clamping force, etc.) they're indistinguishable for all practical purposes. In any sensible table of metric screw sizes you won't even find any entries except for preferred sizes.

My suspicion is that it's them folks deeply wedded to the imperial system, but forced to "go metric" for reasons beyond their personal control. Someone sticks a finger in the air and decides that a screw needs to be "about \$\frac{1}{10}\$". They open up Machinery's Handbook, scan down a table of metric thread sizes and pick, by calculation, the first that's greater than 0.1". It has to be something like that because if you picked a #3 screw (basic size 0.0990" = 2.5146mm) when hunting for the closest metric equivalent you'd come up with M2.5 (basic size 0.0984"), and if you'd picked a #4 (basic size 0.1120" = 2.8448mm) you'd either pick a bastard size of M2.8 or M2.9, or the sensible M3.0.

[mnementh]

Blame the Germans and the Swiss and of course, the Japanese. It is my understanding that those oddball tiny metric sizes go back to the wars between all the watchmakers/clockmakers/cameramakers back in the days of the post-war Japanese manufacturing Renaissance and the advent of JIS fastener standards. I know those old Panasonic & Sony portable radios, tape recorders and video cameras were chock full of those oddball sizes; I cursed them a great many times when I was working in the AV lab.

mnem
As I also cursed brittle JIS screwdrivers... which seemed to be the only kind we could order from our catalogs.

[mnementh]

Proudly pocket protector free zone here!

I never had the nerd-pack in my pocket, tho I did for the longest time keep a 4-color Bic and a Cross SS Pen/Pencil. When (not if) the Bic leaked, I took my licking (yes, snickers and snerks were still de rigueur at the time) like a man, gawddammitt... and went & bought a new shirt at lunchtime. 

I did, however, for the longest time sport the junkyard warrior's sidearm pack... A Gerber Gator lockback, Gerber MP600 multipliers, and a 2AA Maglite (later replaced with various much more powerful LED lights of similar form factor) in holster between the two. I still find myself absently reaching for one of them whenever I find myself in a random "mechanicking" situation.

When I was a young noob engineer working mostly on the manufacturing floor, the exigencies of the workplace demanded that the Gator pigsticker stay at home... I did often get sideways glances over just the MP600, which usually vanished when I flicked them open and performed some minor maintenance miracle.

I did eventually learn to wear a polo shirt and keep them under it in the interest of fitting in with more polite society; learning to keep my mouth shut took considerably longer.

mnem
*lessons hard-learned*

[mnementh]

Random Booty-Fab/Empirical Engineering Timewaster:



mnem
*impairing productivity since nineteen-mumblety-mumble*

[McBryce]

You know that if you paint them bright red the car goes faster (or at least all those would be tuners seem to think so).

McBryce.

And if it says "Brembo" on them it's even faster.

Bullshit.
You need one of those.

And one of these to launch it 

Nearly lost a hand with a squib one time. Not to be messed with!

McBryce.

[AVGresponding]

Discord is waking up