Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

Yeah... as in in "He knows it's big enough, he doesn't need to measure it that precisely..." and the latter part implied, of course.

I need to remember that I'm talking to a room full of Engineers, who are not always in touch with their inner dirty-minded primate...

mnem
 

Have you been paying no attention boy? This room is chock full of dirty-minded primates. OK, so one of the dirtiest minded, and so monkey-like to actually say "Ook, Ook" in reply to at least one message is missing at the moment, but his absence hasn't changed the composition of the audience significantly.

I didn't say that; I chose my words very carefully when I said "not always in touch with their inner dirty-minded primate..."

That, I think, is maybe one of the defining characteristics of the breed... the ability to be nerd-sniped; to think entirely aboot the technical aspect of something, to divorce one's mind so completely devoid of the (often very obvious) baser instinctual responses. A real nerd... an engineer... can actually nerd-snipe themselves.

mnem
some actually take a perverse pleasure in doing so...

[med6753]

I'm seriously considering putting this guy out on my local CL. I'll make sure all critical calibrations are in spec but I won't perform a PSU re-cap. The other Type 454 will be a keeper.

Others should have fun too?

 

Doing a re-cap will eat into any potential profit. Purely driven by the evil dollar. 

[mnementh]

Yup. Proof that your hollow-state Tek collection is purely a labor of love.

mnem
also, they're prettier than a space heater. 

[xrunner]

Vintage HP Scope 120B : I managed to get it in the end !     ...
Will be proud of owning this little gem once it's all working and shining again ! It SO did not deserve to die !!!   

Glad you were able to save it from the choob vulture. Please share his its eBay username so we can burn the bastard in effigy avoid supporting the vulturism and maybe save a few bits of vintage gear ourselves.

mnem
 

Not Ebay !  It's from our French equivalent of CL : " Leboncoin.fr".

Here is the ad, still online :

https://www.leboncoin.fr/bricolage/1984157768.htm

Guy has no other items listed, he is not a "serial seller" at first glance...

Congrats Vince on the hp "ancre de bateau". 

[mnementh]

!!!   BREAKING NEWS !!!

Vintage HP Scope 120B : I managed to get it in the end !    

Congratulations! I'm glad, that it finally find his way to you. 

I think I have already found what I could do with it : its abyssal 450kHz , oops sorry, 450kc bandwidth, is hopeless. However, it's got a large CRT, a cool retro look, practical banana jacks instead of BNC or UHF connectors as inputs. Has an external horizontal amplifier input, so could be turned into an XY scope I guess. Also, it has a Z input, and located at the front to boot, which is rather uncommon, it's usually hidden at the back !
So it's pretty useless as a scope, but would male a beautiful and very practical XY display machine, for all sorts of XY goodness, me think !   

Perhaps this kind of scopes has been used for audio stuff.
One application I could imagine would be measuring the synchronisation fluctuations
of tape recorders. This can be done very well with the representation of Lissajous figures (XY-mode, of course).

anyway, I'm wishing you a lot of fun bringing this nice scope back to life. 

IMHO, it screams to be kept out and set up on the back bench, semi-permanently attached to a simple homebrew junction tester. 

mnem
 

[Brumby]

I don't have a pair of calipers.

     Me sad now.   

[beanflying]

Due to @Meds short Arms (surprising given the Tek Lumps he moves) and long pockets this is what is needed by his Foot Fetishist Fab 

We all of course need a larger set of Calipers for ...... 

[cyclin_al]

   

Sometimes you have to wonder aboot our connected world... Yesterday I went shopping for a 15mm cone wrench...

Huh?   Here you go:   https://www.mec.ca/en/product/5048-516/DCW-Double-Ended-Cone-Wrench   Price is only $8.15 CAD
It is out of stock at your local store, but they have it downtown so you could pick it up today.

Huh... never heard of them... Mountain Equipment Co-op...?  Also did not come up in my local search for "cone wrench", either on webcrawler or Googs.    I guess the owners probably don't pay for search-engine top-ranking out of principle, given the backstory on their Aboot: page.

The closest I know of from the Corporate Hinterlands south of the border would be Academy Sports & Outdoors; aside from a few boutique outfitters who are more designer outlets than actual outdoorsman shops.

Looked into pick up at store... they show a regular Park 15mm cone wrench at my local store for only $14 which I would gladly pay, but "available for pickup in 5-10 days"... My wrench from Amazon is paid for, and will be here Saturday. I can get either wrench from the downtown MEC tomorrow afternoon... but they are literally down-downtown and I loathe driving there. ehhhhhhh....

I will keep them in mind tho... have already added them to my business contacts. Thanks for the heads-up! 

mnem
 

Don't believe all the hype...  they used to be named Mountain Equipment Co-op.  However, they have been bought out and are no longer a co-operative.  The legal name has also been changed to MEC.  If you note the details, they say membership is free, but that is a marketing gambit to look like they still have the values they once had.

... I used to work there in a previous life.  I miss the staff culturecult that once was...

[Kosmic]

I found another ESI SR1010 transfer standard to add to my collection.



I already have the 100K\$\Omega\$ and 10K\$\Omega\$ per step, and now just got the 10\$\Omega\$ per step. Unfortunately missing the original calibration sheet.



So I measured each resistors quickly and R1 looked a bit weird. Normally those resistors are really close in value to each other and you normally can't really make the difference with a 4.5 digits meter.

Decided to open the box to see what was going on.



WTF


Look like someone thought that a 10\$\Omega\$, 1%, 50W Dale power resistor was a good substitute. It's clearly not since those resistors are all siblings and were produced exactly at the same time by hand with the same spool of wire. There is unfortunately no substitute for the lost resistor. But it's not a huge issue since normally only 10 of those resistors are used together (in parallel or series).



I will probably just remove the ugly Dale resistor, recuperate the binding posts and plug the holes with a 3DP cap.

[mnementh]

mnem
*kicks that "someone" in the junk*

[med6753]

Wow, pox on the Gorilla burned up the original and double pox on the Gorilla who thought that replacement was an acceptable substitute. The integrity of that unit is now compromised.

If you're going to use it strictly as a reference and not for design work where appreciable currents might be involved why not hand select a 0.01%, 10ohm resistor?

Did the seller advert it as "non-working" or "fully functional"? If the later you might have a case for a refund.     

[mnementh]

Due to @Meds short Arms (surprising given the Tek Lumps he moves) and long pockets this is what is needed by his Foot Fetishist Fab 

We all of course need a larger set of Calipers for ...... 

That's awesome... exactly the same as the 8-32 screw I was working from on a guess. What's coming off the printer has a 0.325-0.330 ID on the screw recess.

mnem
*toddles off to ded*

[Robert763]

I found another ESI SR1010 transfer standard to add to my collection.


I already have the 100K\$\Omega\$ and 10K\$\Omega\$ per step, and now just got the 10\$\Omega\$ per step. Unfortunately missing the original calibration sheet.

So I measured each resistors quickly and R1 looked a bit weird. Normally those resistors are really close in value to each other and you normally can't really make the difference with a 4.5 digits meter.

Decided to open the box to see what was going on.



WTF


Look like someone thought that a 10\$\Omega\$, 1%, 50W Dale power resistor was a good substitute. It's clearly not since those resistors are all siblings and were produced exactly at the same time by hand with the same spool of wire. There is unfortunately no substitute for the lost resistor. But it's not a huge issue since normally only 10 of those resistors are used together (in parallel or series).

I will probably just remove the ugly Dale resistor, recuperate the binding posts and plug the holes with a 3DP cap.

If you do remove the binding posts can I please buy one from you?
My 100R unit has a broken post 
It seems a bit like karma as I have supplied HP binding posts to a TEA contributor.

[beanflying]

Due to @Meds short Arms (surprising given the Tek Lumps he moves) and long pockets this is what is needed by his Foot Fetishist Fab 

We all of course need a larger set of Calipers for ...... 

That's awesome... exactly the same as the 8-32 screw I was working from on a guess. What's coming off the printer has a 0.325-0.330 ID on the screw recess.

mnem
*toddles off to ded*

I actually opened up that file in Fusion for the first time since I made mine. The Aluminium core was measured ACCURATELY thanks to my $10 Calipers in Inches While just to be contrary I modeled the outer Plastic bits in mm's.

The recess on the model you are playing with was 9mm diameter or about 0.35 so it was fine without tweakage  Interesting looking at the workflow I used at the time compared to what I would do now too..... so much more simple when you know how.

In other Ozzie news our State is having a weeks stay at home after a South Australian crossed the border with the human plague. Apparent Mouse Plague in 'record media numbers' but no issue with Traps or Baits on the shelves but the other plague has again caused a Run on Toilet Paper - zero stock after 8 hours from announcement

[Doddy883]

Just got a Testo 760-2. Definitely did not need another meter, but these are seriously cheap on UK Amazon right now! (£52). Haven't had a play with it yet, but I love the form factor - similar size to my Flir DM66. It's got CSA, TUV, CE approval, and it comes with some nice silicon leads. It's a bit unusual with the buttons rather than rotary switch, but I think it looks cool. It'll be my first dual display meter too

[med6753]

I was always curious as to why the Tek 485 did not closely resemble the 465/475 series even though they were available for sale around the same time. I now have the answer. It is very obvious that the design team for the 453/454 also designed the 485.

[beanflying]

Think I posted this a while ago but so maybe a repost as it is worth a watch

[Cerebus]

Back on the subject of not owning at least one set of calipers. I just had to mechanically measure something electronic and it suddenly struck me that it's something that I'd have thought everybody needs to do on a fairly regular basis.



I want to get some individual pin sockets to make a test jig for the OCXOs and I wanted to confirm what the drawings had to say about the pin sizes (0.8mm±0.1mm). Lucky I did, as the tolerance on these is quite a bit wider than claimed. Seeing as they're reclaimed parts I'd expect them to perhaps be a bit oversize (solder residue) but undersize I didn't expect. If I'd gone for the sockets I'm currently looking at there's a real risk that they'd have been too big.

I don't know how someone can get by without at least a set of callipers, and probably a micrometer as well. OK, you don't need an over the top Mitutoyo micrometer like the one above (I got a very good deal on an ex-display instrument, basically half price) but even my crappiest Clarke callipers reliably measure to 0.001" (and only cost £15) which is good enough to check wire and pin sizes.

[Robert763]

Just be wary of the very cheap digital calipers. I had one that had a small error. I bought a bunch of round stock in the wrong size as a result 
I good, cheap check, lacking a slip gauge, is a ball bearing. Singles or small quantities can be bought on ebay for pennies. aviod the "slingshot ammo" ones though.
If you get the imperial 11/32" (8.731mm) ones they do double duty as dies to repair dinged BNC or TNC sockets. Just plice in socket and gently tap with  small hammer. Obviously keep the size check ones separate from the ones you hav hammered
<£3 for 10  https://www.ebay.co.uk/itm/272320385111

[Peter_O]

med... which do you like better; the gloss black or satin black filament? Finished product is pretty close to the correct dimensions now; just trying to get the surface looking presentable.

mnem
 

You can do a smooth finish with a lathe. Works fine with PLA, PETG or ASA.

Same print before and after:



More Images here: https://drucktipps3d.de/abgedreht-glatt/

[Cerebus]

Just be wary of the very cheap digital calipers. [snip]

That's a good point. The cheap mechanical ones (like my Clarke imperial dial caliper) tend to be more reliable. Also the cheap Chinesium digital calipers are well known for eating batteries such that, by the time you need them next, you pull them out to find that they've got a flat battery. As you say, a sanity check against a known standard is always a good idea and nothing beats a good ball bearing for precision at a rock bottom price.

Clarke Calipers:

[Cerebus]

You can do a smooth finish with a lathe. Works fine with PLA, PETG or ASA.

Same print before and after:



More Images here: https://drucktipps3d.de/abgedreht-glatt/

Me no understand the logic here. If you've got a perfectly good lathe why would you be wasting time waiting for the thing to print and then turn it down to size if you could turn it out of stock in one step in the first place?

[Specmaster]

Just be wary of the very cheap digital calipers. I had one that had a small error. I bought a bunch of round stock in the wrong size as a result 
I good, cheap check, lacking a slip gauge, is a ball bearing. Singles or small quantities can be bought on ebay for pennies. aviod the "slingshot ammo" ones though.
If you get the imperial 11/32" (8.731mm) ones they do double duty as dies to repair dinged BNC or TNC sockets. Just plice in socket and gently tap with  small hammer. Obviously keep the size check ones separate from the ones you hav hammered
<£3 for 10  https://www.ebay.co.uk/itm/272320385111

Yes, some very cheap ones can be affected by noise, especially noise coming from fluorescent bench lamps, I have one but since switching to a LED lamp which has its power on a long lead, that error has now completely been eliminated. The error is easy to test for, just measure something and then move the calipers about on the bench and observe the reading for any variations.

[vk6zgo]

What...you don't have a pair of calipers!!! Just grab yourself a cheapo pair of digital ones, they are so bloody useful. I struggle to comprehend that don't have a pair.

I knew someone was going to bust my balls over having no calipers.    Since when does an ELT tech and sometimes carpenter need them?  If I were a sometimes machinist then sure.....but I'm not. 

Even having one is no guarantee it will be available when you need it------my "El Cheapo" one seeems to find
an unending number of spots to hide in.

[Brumby]

Just be wary of the very cheap digital calipers. [snip]

That's a good point. The cheap mechanical ones (like my Clarke imperial dial caliper) tend to be more reliable. Also the cheap Chinesium digital calipers are well known for eating batteries such that, by the time you need them next, you pull them out to find that they've got a flat battery.

My experience also .... but I found a simple solution.  Can you spot it?



My AUD$19.95 Aldi special (of many years ago.)