Test Equipment Anonymous (TEA) group therapy thread

[TERRA Operative]

Well, a few hours in 6% H₂O₂ at around 50^oC is a good cure for cigarette stain and stink in rubber membrane buttons. The two trips through the dishwasher made them clean, but the hydrogen peroxide got them whiter and stink free.

The buttons from the TDS620 are looking (and smelling!!) waaayyyy better than when they started, not perfect but enough to make me happy. Those buttons were positively yellow, tending to brown when I started...


Now to fix that PSU so I can see if this thing actually works, and find a replacement foot. Anyone got a spare foot for one of these things? 

[vk6zgo]

mF for micro Farad is just wrong. µF is correct.

Just so, but uF is also acceptable at a pinch.

Using mF is as pig ignorant as mS for milliseconds, or using kW where kWh is relevant (or vice versa).

Back in the day, milliFarads were pretty much the thing of fantasy for most people, & those few that did exist were called out as multiples of 1000uF, ie, 1000uF, 2200 uF, etc. (& yes, I've forgotten how to do "micro" symbols on this device).

As "mF" was virtually unused, many  thought "Everybody will know what I'm talking about", & went with "mF" for "microFarad", or even, (horror of horrors), "MFD"!  
Remember SI didn't exist for much of this time.

[mnementh]

Mrs. GreyWoolfe and I did the diet thing for years....

Yeah, I've done the Dub-Dub. Did not work for me. Period. I'll worry about the "changing my lifestyle" self-affirmation stuff once I actually lose the weight. Again.

Honestly, the more I actually do hard Keto, the easier it becomes to just not eat stoopit shit...

SWMBO & I have been on "Lite 'n Easy" for a couple of years, now.
I dunno if it is an Oz only firm or not, but anyhow, it works like so:-

On Friday, we have several large styrofoam boxes delivered, containing our meals for the week. The "Dinners" are all frozen (like TV dinners, but a couple of levels better quality), the lunches are varied, some just refrigerated, some frozen, mostly a mixture.
We opted out of breakfast.

Most of the time, we have very little problem "sticking to the program"...

Actually, that's a good point... @GreyWoolfe - Are you doing the Dub-Dub food, where everything is premade, or are you doing the recipe program, where you cook it yourself?

I did the latter, as I couldn't see the point in buying TV dinners when I enjoy cooking, and already know how to weigh/calculate carbs & cals/record my intake. 

mnem
*toddles off to buy some metal for 3DP upgrades*

[vk6zgo]

I don't mix them with my existing precision resistors... better safe than sorry. That being said, I picked one of them up at random, colour bands as can be seen on close-up picture below, are RED - RED - BLACK - GOLD - YELLOW.  So if it's a resistor, should be 22R + Yellow tolerance band.. .and I measured it, it reads spot on 22R. So maybe yellow is a valid tolerance colour ?!    I knew of red and brown for 1% and 2% , easy enough to remember, but Yellow... that doesn't ring a bell.

My first thought on the additional yellow band is that it's either a temperature coefficient marking or a reliability rating band, but I wouldn't expect to see those on what appears to be a 5% tolerance carbon film resistor, so I'm kind of at a loss on exactly what it is.

-Pat

Good idea !

Found this colour table that's more complete than most, and it does indeed say there can be a colour band for tempco !  And yellow is a valid colour... means 25ppm... twice better than my metal 1% resistors ! 

So.. it's a mere 5% resistor, but a stable one... I learned something new today, cool !

Yes, something I learnt back when I was a store person doing a stocktake:-
There is a difference between high accuracy  & high stability resistors.

The former are very close to their nominal value, under specific temperature conditions, but just as prone to wander in value outside that favourable range.
The latter may be not so acccurate, but change very little with temp.

In practice many "precision" resistors try to do both!

[Vince]

@Cerebus : thanks for the details on the (vinyl) cutter. Sounds like a nifty little device especially for the price you go tit for used !
Making stencils to paint stuff appeals to me, easy way to customize stuff...
The technical limitations you detailed clearly make it unsuitable for my main purpose though. As one could expect, doing lots of fine text is not where it shines, so would still need to investigate the other options.

@ resistors : well it's a bit of a mess... I think it's just not worth me keeping these precision resistor (be it value precision, or tempco) around. I mean if I can't even be sure 100% what the bands means, forget it.
Plus it's a pain to read them one by one to see what I have. Plus I probably won't need more than one of those every year at best in averages, let's be real, I am not into precision stuff day and night. So the chances of finding exactly the value I need, is slim to none, and the tremendous amount of time it would take to destroy my eyes looking at all those 1/4W resistors... to then realize no, I don't have it... just not worth my time.
So I think I will just throw them all away, bar the few that are clearly marked in plain English, not colour bands.

Workflow for the rare occasions I might need a precision resistor will be I think :

1) Standardize on 1% metal resistors, E24, as a daily driver. Then if more precision is needed, or an out of E24 value is needed, then :

2) If it's a repair, just put a couple resistors in series or // as required, to get close enough for proper operation.

3) If it's a new design, use a fixed resistor + a trimmer combo, at prototype stage. Then once the actual value is figured out, order the proper resistors, brand new, for the next prototype or final product.

@ Terra operative : looking much better !   I am sure Dwagon can make you a smurf blue 3D printed foot ! Like he did for Papa smurf for another Tek scope IIRC.


Storage :

- just received today an Amazon package containing 5 plastic boxes. smallish 320x255mm ones, with separators. Except I did not order them (I prefer cases with removable bins).
Called daddy... turned out he bought for me a week ago but forget to tell me about it...
OK so I normally would not have ordered this particular style of cases but... now that they are here and 100% free, and no less than 5 of them... think I will use my imagination to make use of them .?! 
I don't want to use this style of cases to store lots of small / discrete components because once they are in the box, it's pretty much set in stone... you can't reorganize the case, or grab the contents of a "cell" to empty it on the bench and search for what you need. But... I guess if I put the components in small zip-lock bags, then put the bags in the case, that would fix that problem.
Cases could also be used to store bigger pieces where this is not such a problem.  Like say I don't know, organize all my coaxial sockets and plugs and adapters and what not.
If I remove a few dividers to make larger cells, I guess I could use it to store stuff for prototyping, like small bread boards, small SMD->TH IC adapters, Dupont wires, strip headers, and what not.
Yeah, I guess I will figure out ways to make use of those cases....

Then went to the flower shop to go get my amazon parcel containing my second batch of small Kraft paper envelopes to finish sorting my resistors.... only to find a closed door.. they decided to close on Wednesday afternoons, that's my luck   

Then I drive all the way to the other side of town, to get to that H/W store to get another of these smurf blue drawer units. The medium size one that used for the electrolytic caps, with several sizes for drawers. I am thinking of using that sort all my other caps : film caps and ceramic caps. I checked their website before making the trip of course, to ensure they still had them in stock. They did... only ONE left ! No kidding. So I spent an hour driving there and back, only to find out that yes, they did have one left but... it was badly damaged !!!  the frame is metal, and the top of the unit was concave, and the whole frame was kinda skewed. Clearly took a bit hit from the top 
So I lost one hour of my life and so expensive petrol, bummer.
Asked a seller in there. He looked it up in his computer, says some more have been ordered, 5 units, which should be there on Monday.


So... I don't have my envelopes, I don't have my smurf blue drawer unit... but I do have 5 unexpected plastic cases.. so it's a bit f mixed bag today ! 

[tggzzz]

mF for micro Farad is just wrong. µF is correct.

Just so, but uF is also acceptable at a pinch.

Using mF is as pig ignorant as mS for milliseconds, or using kW where kWh is relevant (or vice versa).

Back in the day, milliFarads were pretty much the thing of fantasy for most people, & those few that did exist were called out as multiples of 1000uF, ie, 1000uF, 2200 uF, etc. (& yes, I've forgotten how to do "micro" symbols on this device).

As "mF" was virtually unused, many  thought "Everybody will know what I'm talking about", & went with "mF" for "microFarad", or even, (horror of horrors), "MFD"!  
Remember SI didn't exist for much of this time.

I don't think "SI not existing" is practically true...

CGS units were established in 1874, the MKS units shortly afterwards, and the ampere added in 1939. SI units were formally established in 1960.

The Jar as a unit of capacitance (1111pF) was in use in at least 1931, but I've never seen it used in anger. The Farad was in use in 1881.

Ad for MFD, at least they aren't actively using the wrong unit, cf second/Siemen.

[Cerebus]

mF for micro Farad is just wrong. µF is correct.

Just so, but uF is also acceptable at a pinch.

Using mF is as pig ignorant as mS for milliseconds, or using kW where kWh is relevant (or vice versa).

Back in the day, milliFarads were pretty much the thing of fantasy for most people, & those few that did exist were called out as multiples of 1000uF, ie, 1000uF, 2200 uF, etc. (& yes, I've forgotten how to do "micro" symbols on this device).

As "mF" was virtually unused, many  thought "Everybody will know what I'm talking about", & went with "mF" for "microFarad", or even, (horror of horrors), "MFD"!  
Remember SI didn't exist for much of this time.

SI has existed for longer than many people think, 62 years to be precise, and in proto form for 74 years.

"The 9th CGPM [in 1948] also approved the first formal recommendation for the writing of symbols in the metric system when the basis of the rules as they are now known was laid down."

"In 1960, the 11th CGPM synthesised the results of the 12-year study into a set of 16 resolutions. The system was named the International System of Units, abbreviated SI from the French name, Le Système International d'Unités."

[AVGresponding]

There's a Datron 1071 7.5 digit meter for auction at https://www.ebay.co.uk/itm/165326135622

It shows "error 6", but there's a high probability that's because the two inputs are connected during the test.

Hold my beer...

[Cerebus]

Willing to bet money the battery ran out and it will also show error 5 and...

ie, cal lost.

Well, my 1061 has error 5 = dc and "fail" is cal lost. But ISTR you have experience with 1071s.

I checked the manual for the 1071 and error 6 refers you to the ohms self-test which says (and I have to do this the hard way because the manual I have is not OCRed):

3.4.3 Test

During the self-test routine (actuated from the front panel or remotely programmed), the Ohms Converter is checked for correct operation. The circuitry is placed into the 10kΩ range as described in Section 3.2.1.3. Filter is selected and F.E.T. Q5 'closed' from M9-1 causing R8 (9.76kΩ) to be placed between I+ and I-. Thus with I+ and Hi, I- and Lo connected (2-wire if front panel input selected), the DC Isolator (which is also in the TEST mode) measures the voltage developed across the resistor (approx 1 volt). ,,,

So yeah,  a short between Hi and Lo would ruin your day by falsely generating error 6.

[Cerebus]

There's a Datron 1071 7.5 digit meter for auction at https://www.ebay.co.uk/itm/165326135622

It shows "error 6", but there's a high probability that's because the two inputs are connected during the test.

Hold my beer...

Ah. Changing our name to "Billy Bob" or "Bubba" are we? 

[AVGresponding]

Just call me a cab...

Seriously, I have a DMM addiction problem, and showing me pictures of 7.5 digit panaplex models doesn't help.

[tggzzz]

I see there are now two bids on it. Fight. Fight. Fight.

Seriously, I have a DMM addiction problem, and showing me pictures of 7.5 digit panaplex models doesn't help

It might not help you, but it removes temptation from me 

I'll make do with a 1061 (Panaplex), 7081 (VFD), 7151 (LCD), 34410A (VFD), Keithley 2K, Fluke 8300A (nixie), Fluke 8125 (nixie). I'm only planning on significantly adjusting one of those, sometime.

[AVGresponding]

It'll be fine, I'll get outbid. The only meters* I'm still really keen to acquire are a Solartron 7061/71 and a Prema 5.5/6.5 digit with red dot matrix display. A Keithley 2001, HP 3457A, or Fluke 8846 could all tempt me if the price was right.

EDIT: *Bench meters. You could easily lead me over a cliff with any number of handhelds...

[Vince]

It'll be fine, I'll get outbid. The only meters* I'm still really keen to acquire are a Solartron 7061/71 and a Prema 5.5/6.5 digit with red dot matrix display. A Keithley 2001, HP 3457A, or Fluke 8846 could all tempt me if the price was right.

EDIT: *Bench meters. You could easily lead me over a cliff with any number of handhelds...

In your case, you are lucky in that you suffer from another disease, and the two happen to nicely balance each other out, to keep you out of trouble : as soon as the auction  goes above START-PRICE + 50 pennies, you throw your arms in the air yelling : " NO WAY I am going to pay THAT MUCH for it " !!!! 

[Cerebus]

Just call me a cab...

OK, Mr. Calloway.

P.S. Have you got Minnie's number?

[AVGresponding]

It'll be fine, I'll get outbid. The only meters* I'm still really keen to acquire are a Solartron 7061/71 and a Prema 5.5/6.5 digit with red dot matrix display. A Keithley 2001, HP 3457A, or Fluke 8846 could all tempt me if the price was right.

EDIT: *Bench meters. You could easily lead me over a cliff with any number of handhelds...

In your case, you are lucky in that you suffer from another disease, and the two happen to nicely balance each other out, to keep you out of trouble : as soon as the auction  goes above START-PRICE + 50 pennies, you throw your arms in the air yelling : " NO WAY I am going to pay THAT MUCH for it " !!!! 

It'll take more than that to elbow me aside

[Vince]

75p then  ?! 

[tggzzz]

Just call me a cab...

OK, Mr. Calloway.

P.S. Have you got Minnie's number?

I wonder how many people will understand that. I do, due to my father's tastes.

[Andrew_Debbie]

HP6235A arrived.  Throwing caution to the wind, I plugged it in for a quick check. 

Looking good.   £60 well spent?   



AC (ripple) check.   I'll put the 'scope on it at some point.

[Per Hansson]

This thread of mine comes to mind when it comes to mF

Some people really don't get SI units, and I don't mean you, Per!

Careful: don't short that cap out or you might just cause the next big bang!
In fact I think we now understand the origin of the big bang!

Cerebus: Please keep the pictures of the Variac coming, you might just coax me into designing something better for mine than the cardboard box it was delivered in!

I'm also curious about the cute Tektronix 221 posted before, did someone here get it?
Actually very nice of you to post that, since an ad like that will always be missed by me since it lacked the model number of the unit.
I did send the seller a message (in my broken German) asking if he would ship it to Sweden but got no reply...

Also kept an eye on that very honest Tektronix 2465B DM but it did go a bit high.
Especially considering the lost calibration and leaking SMD caps for 7 more years since those pictures where taken.
But I do hope it finds a good home!

[Cubdriver]

Just call me a cab...

OK, Mr. Calloway.

P.S. Have you got Minnie's number?

I wonder how many people will understand that. I do, due to my father's tastes.

I do thanks to a movie that came out more than 40 years ago.  (damn I feel old now!)


-Pat

[m k]

I also tried some arrangements once but lost my stamina with higher power resistors.
The last(keltainen/yellow) is all the rest.

BTW,
my weight thing was actually just nuances.
Don't have any food addictions either so it wasn't even near what it could be.
Surely I like to eat something more than something else but that's different.

[Neomys Sapiens]

HP6235A arrived.  Throwing caution to the wind, I plugged it in for a quick check. 
...

...

That poor power supply! Having undoubtedly survived much, proving that it still works faithfully in the hope to secure a good new home - only to get mounted by a blaring, gaudy abomination!

[mansaxel]

I am helping in the only way we know how to around here. I'm also pointing out the crafting features that give it high WAF/GAF/PAF. 

In my case I -- while am grateful for the help offered -- did not need it, because Wife has already bought ${DEVICE}. My challenge lies in getting access to it!

[mnementh]

HP6235A arrived.  Throwing caution to the wind, I plugged it in for a quick check. 
...

...

That poor power supply! Having undoubtedly survived much, proving that it still works faithfully in the hope to secure a good new home - only to get mounted by a blaring, gaudy abomination!

If you're realllllllly lucky... the offspring might be a couple shiny new Lambdas... 

mnem