Test Equipment Anonymous (TEA) group therapy thread

[mnementh]

Maybe there is a cure for TEA. I mean, looking too long at THAT thing might very well break any affection for test equipment. This thing is so fecking ugly that I did not dare to post a picture of it.
Steel yourself for something really, really horrible and take a look:

https://www.ebay.de/itm/294250484573

Hurrrlk!

Soviet ТЛ-4М (ТL-4М) voltmeter from the Bay of Pay. It shipped from Latvia and I just got it yesterday.

It's bright orange, and it includes the battery cover. There are brass inserts in the plastic for the battery cover to screw into. Looks like one of the precision wire-wound resistors is toast and the glass meter cover is cracked. I tried the DC voltage up to 300V and it's reasonably accurate. It has 1,000V AC and DC modes but I don't have anything that makes 1000V DC (yet!). It's all hand assembled. Some Deoxit faderlube helped the mode-selection wheel to turn much easier. The switch in the lower left marked - ~ is the DC/AC mode selector switch. That's different. I grew up during the cold war, which makes this meter all the more interesting. Does anyone have any idea what year this was mode? I'll have to cut and paste some Cyrillic characters into a translating site to read what is written on the back.

Ahhh! You got it! Lucky plucky duckduck! 

Lookit that pseudo-PCB... just holes drilled through FR4 and daisy-chain wiring. I love it!

I wanted it, but shipping to GWN was either not available or fraught with the usual not-EGS hazards so I backed away.

mnem

[mnementh]

Eutectic alloys like 63/37 have a solidus/liquidus temp that is very nearly the same.

You know the most intriguing words. 

Since it appears we have some experts around here, is there a limit to the shelf life of 60/40 and ROHS solder? I've bought a life supply of both, some years ago. Just wondering...

Ummm... taken from the coursework when they sent me to school for soldering back in the day. Kester-sponsored classes.

All metals have a eutectic point... but flowing/liquid point can be considerably higher. These are important considerations when you're trying to bond stuff with liquified metal.

mnem
 

[Cerebus]

Eutectic alloys like 63/37 have a solidus/liquidus temp that is very nearly the same.

A eutectic has a precise temperature at which it melts completely or sets completely - not nearly the same, exactly the same. It's half of the definition of a eutectic, the other half being that the melting point of a eutectic is lower than the melting points of the alloy's constituents.

A eutectic has a phase diagram like this:



At the eutectic alloy composition there is no temperature point where there is liquid of one element and solid of another.

[Neper]

Now, that certainly makes sense.

[Saskia]

could not resist ...

[Saskia]

@mnem congrats for going all in.  And for your tinkering on those cameras.

in other news, my Nakamichi 680 arrived today. Need to unpack, due to recent events I had not gotten around to it yet.

[med6753]

Oooh mine. Only up the road and buyer collects.

https://www.ebay.co.uk/itm/194381196324

Looks real clean. How high are you willing to go?

Edit.....mine was $40 USD and it worked other than needing a cleaning/calibration and of course I did a recap.

Probably about £45 I reckon. Always wanted one so worth the punt.

Be aware that if you do get it that the PSU went through a major redesign during the product life cycle. One version of the PSU is contained within the 422 service manual. The other version is a separate manual. 

[dl6lr]

Close-up pics below. Took one of the pens out and measured it more accurately, using calipers this time.  I would say they are 23,25mm long by 4,9mm in diameter.

Ah, this is the same plotter crap that commodore used way ago in its vic 1520 (and Sharp too). Besides the pens (originally in two flavours: ball pens and felt tip pens) being dry or empty every time you needed them, the plastic (nylon?) gears molded to the motor shaft tends to crack.

[Robert763]

Even better is a non-interference design like the FIAT JTD 1.9 120hp which was also used in the Vectra I used to have. Despite FIAT it's a very reliable engine.

The 1.9 litre common rail diesel? Someone correct me if I'm wrong but wasn't that engine originally developed by Alfa Romeo before the takeover by Fiat?

If it’s a 1.3 variant of that engine it’s a fucking turd. Absolute shit show beyond all compare. I owned one.

My bad, I meant Alfa Romeo, not FIAT. Still, given they have a similar (well deserved) reputation for unreliability, I stand by my use of the word "despite"...   

You’re excused 

This time 

The 1.3 is not the same. I had a Croma with the 1.9 16V mJTD 150 HP version and that was an excellent engine. It also made a lie of current wisdom that if you put ANY petrol in a common rail diesel it will wreck it as soon as you start it or even turn the electric pump on. On a run back from Cornwall to Cambridge via Bristol in filthy weather I stopped for fuel. It ws not a brand I normally used and I picked up the black pump handle. SWMBO then distracted me by asking if I wanted nything from the Kiosk. I fuelled up, later calculation showed I added more than half a tank. SWMMBO paid which is unusual. I'd got straight back in the car because the rain was almost horizontal.
So a little while later doing the speed limit down a long hill the car felt a bit judderry but I thought it was just wind buffeting. Stopped in Bristol for about an hour visiting a friend. Came out and the car was slowwer to start than usual but I put oit down to the very steep hill we were on. Then on the M4 I started thinking about it and asked SWMBO if she had  the receipt but it was in her bag in the back. I pulled into the next services, dug out the receipt - UNLEADED 
Well sod it I'd done about 150 miles on it so any damage was done. I topped the tnnk up as high as posible with premium diesel as it contains more lubricity additives and drove home. Put some diesel additive with a lubricity agent (many are just IPA) and changed the fuel filter. Over the next week or so I topped up the tank with premium when it was down a quarter twice and then half then ran it down.
The engine did another 50,000 miles before I sold it without muissing a beat. It's still registered as on the road.
The A would hve told me not to start the car and charged e £200+ to drain the tank nd flush the system......

[tautech]

- What the root problem is, is not a chemical recipe that would REQUIRE silver content for the ceramic strips to be happy. Rather, what damages the ceramic strips is too much heat /temperature for too long. Tek using silver solder (lower melting point than regular 60/40) AND recommending a low power iron on top of that, is them trying make everything they can to reduce the temperature applied to the strip. That is all there is to it I think.

No, the issue is that the silver plating on the ceramic strips will dissolve into the solder if there isn't already silver in the mix. It still will with silver in the solder, but much more slowly,

Interesting ! I wonder though why Tek didn't even hint at that even though they had a special paragraph in the manuel warning about the soldering of teh strips. Seems odd.

A small quantity (2-3%) of silver has little, if any, effect on the eutectic point of solder.

You have to be wrong... it's Tautech a few years back who told me I would just fall in love with the lower melting point of the silver solder. I remember vividly.
Tautech is never wrong. Tautech please show up.

I'm here and still catching up with the thread..... 
The 1 lb roll I brought years and years ago is still my favorite for a lot of work although I've always used it sparingly such was its cost. IIRC it was advertised at lower temp melting and it certainly is but I doubt I can find a datasheet for it now however the old RS catalogues stashed will have some info about it.
Other solders I have have more aggressive fluxes which for rework can be more helpful but sometimes with this modern PB free muck it's good to have lower melting options to blend with it so to get components out without cooking the PCB so much.
I hate that PB free muck with a passion so much so my PB avatar was selected to display such. 

[Robert763]

Oooh mine. Only up the road and buyer collects.

https://www.ebay.co.uk/itm/194381196324

Looks real clean. How high are you willing to go?

Edit.....mine was $40 USD and it worked other than needing a cleaning/calibration and of course I did a recap.

Probably about £45 I reckon. Always wanted one so worth the punt.

Thanks, I know what to bid now..... 
Only joking 

[dl6lr]

About NiMH instead of NiCd: NiMH are not good to hold the charge for a longer time. The good old NiCd will do the job here better.

I beg to differ. Good LSD cells like eneloop will hold the charge far better than the old NiCd cells ever did. NiCd had about 10-20% self discharge per *month*. LSD-NiMH have only 10-15% per *year*.

[mansaxel]

I hate that PB free muck with a passion so much so my PB avatar was selected to display such. 

Most ROHS solders are pretty bad if you're used to and use them just like poison solder. The unleaded Balver Zinn that we did a group buy on in here is my new favourite. I alternate between it and a Multicore 60/40 roll for repair work. I have a more conventional ROHS roll from Stannol too, but I'm not very fond of it. Getting an iron suited to it made things a lot better, though.

Lead is bad for you, seriously so. Working to avoid it is worth some compromises.

[Cerebus]

Close-up pics below. Took one of the pens out and measured it more accurately, using calipers this time.  I would say they are 23,25mm long by 4,9mm in diameter.

Ah, this is the same plotter crap that commodore used way ago in its vic 1520 (and Sharp too). Besides the pens (originally in two flavours: ball pens and felt tip pens) being dry or empty every time you needed them, the plastic (nylon?) gears molded to the motor shaft tends to crack.

And now we have inkjets. Where at least one of the inks is empty every time you really need it. Do I sense a trend?

[xrunner]

Presenting the white 1.3" OLED. There are no flaws (for now) but over and above that it looks much better than the blue one did. Provided it lasts for at least a few days  I'm going to go with it. I got it displaying what I want so might as well get on with the rest.

Next up I'll be modding an aluminum case that held the GPSDO I had (which failed several years ago) before my current model. It more or less matches the current GPSDO case. I'm going to make custom 3D printed panels for the front and back, mount the ATmega328P breakout board inside, RS-232 and power connector on the back, and display panel on the front. Then it will sit next to the GPSDO and run until the OLED fails.

[Vince]

I usually don't like how OLED displays look, but somehow this white over black presentation actually appeals to me... you may have managed to convince me to give these things a chance... might want some day to play with one.

Have an old project that I used a 2x16 text LCD for, and am considering upgrading to a larger as well as graphical display. Was going for a large Matrix Orbital 240x128 graphical LCD initially but now might also want to evaluate an OLED... depending on price and availability of suitable displays (resolution, dimensions, pixel size, pixel gap, type of interface...).

However what's wrong with your display ? Look at the upper right corner, the large " 6 " digit, last of the first row of characters. It looks like some of its "segments" are missing a few dots/pixels here or there ?!    Camera playing up or reality ?

[xrunner]

I usallydon't like how OLED displays look, but somehow this white over black presentation acutally appeals to me... you may hav managed to convince me to give these things a chance... might one some dzay to play with. Have a old project that I used a 2x16 text LCD and am considering upgrading to larger as well as graphical display. Was going for a large Matrix Orbital 240x1218 graphical LCD but now might also want to evaluate an OLED... depending on price and availability of suitable displays (resolution, dimensions, type of interface...).

However what's wrong with your display ? Look at the upper right corner, the large " 6 " digit, last of the first row of characters. The it looks like some of it's "segments" are missing a few dots/pixels here or there ?!    Camera playing up or reality ?

It's the protective film - haven't peeled it off ... 

[Vince]

OK good ! 

[cyclin_al]

A typical German flatjoke.

A joke for the dour-------Scots would probably appreciate it.

That is just too pointed.  I have been so good holding back ... until now.

It is not really the joke that is flat (I have Scottish blood), but it is my Fahrrad that is flat... 

I still have not found the cause of the flat tire in the conversation a couple many of pages back ...

[mnementh]

Eutectic alloys like 63/37 have a solidus/liquidus temp that is very nearly the same.

A eutectic has a precise temperature at which it melts completely or sets completely - not nearly the same, exactly the same. It's half of the definition of a eutectic, the other half being that the melting point of a eutectic is lower than the melting points of the alloy's constituents.

A eutectic has a phase diagram like this:



At the eutectic alloy composition there is no temperature point where there is liquid of one element and solid of another.

They use the term eutectic specifically for 63/37. Yet you and I both know that the change in state with this kind of solder is not that exact. You should be able to use the melting point of 63/37 to set the temp on your soldering station; the closest you can get is within a few degrees.

Is it the product QC? Is it the interaction between the alloy and the flux? Is it sunspots...? I'm going to guess a combination of the above and the response curve/PID loop of the iron.

Doesn't matter. These are the terms the people who make the stuff use, and right or wrong, we have to deal with it.

mnem
 

[Saskia]

Here's an alternative to mutilating test equipment, especially AVO meters:

[Saskia]

A typical German flatjoke.

A joke for the dour-------Scots would probably appreciate it.

That is just too pointed.  I have been so good holding back ... until now.

It is not really the joke that is flat (I have Scottish blood), but it is my Fahrrad that is flat... 

I still have not found the cause of the flat tire in the conversation a couple many of pages back ...

actually we'd say the joke is as flat as the countryside.
Especially if we are in the frisia (North, East, does not matter) where you can see on Monday who will be visiting you for tea on Friday.

[Saskia]

oh woe is me.
the 680 is in neeeeeeeed of an overhaul.
playback: the higher frequencies are missing.
record: way not loud enough
VU display (flourescent) : the bars disappeared about 10 seconds into the test. Need to check for blown electrolytics, ...

That's gonna be a major overhaul. btw the service manual has 130 pages ...

[Cerebus]

Eutectic alloys like 63/37 have a solidus/liquidus temp that is very nearly the same.

A eutectic has a precise temperature at which it melts completely or sets completely - not nearly the same, exactly the same. It's half of the definition of a eutectic, the other half being that the melting point of a eutectic is lower than the melting points of the alloy's constituents.

A eutectic has a phase diagram like this:



At the eutectic alloy composition there is no temperature point where there is liquid of one element and solid of another.

They use the term eutectic specifically for 63/37. Yet you and I both know that the change in state with this kind of solder is not that exact. You should be able to use the melting point of 63/37 to set the temp on your soldering station; the closest you can get is within a few degrees.

Is it the product QC? Is it the interaction between the alloy and the flux? Is it sunspots...? I'm going to guess a combination of the above and the response curve/PID loop of the iron.

Doesn't matter. These are the terms the people who make the stuff use, and right or wrong, we have to deal with it.

mnem
 

eutectic | juːˈtɛktɪk | Chemistry

adjective
relating to or denoting a mixture of substances (in fixed proportions) that melts and freezes at a single temperature that is lower than the melting points of the separate constituents or of any other mixture of them: "the eutectic mixture melts at 183°C" | "silver and copper form a eutectic system".

noun
a eutectic mixture.
• short for eutectic point.
ORIGIN
late 19th century: from Greek eutēktos ‘easily melting’, from eu ‘well, easily’ + tēkein ‘melt’.

[mnementh]

Eutectic alloys like 63/37 have a solidus/liquidus temp that is very nearly the same.

A eutectic has a precise temperature at which it melts completely or sets completely - not nearly the same, exactly the same. It's half of the definition of a eutectic, the other half being that the melting point of a eutectic is lower than the melting points of the alloy's constituents.

A eutectic has a phase diagram like this:



At the eutectic alloy composition there is no temperature point where there is liquid of one element and solid of another.

They use the term eutectic specifically for 63/37. Yet you and I both know that the change in state with this kind of solder is not that exact. You should be able to use the melting point of 63/37 to set the temp on your soldering station; the closest you can get is within a few degrees.

Is it the product QC? Is it the interaction between the alloy and the flux? Is it sunspots...? I'm going to guess a combination of the above and the response curve/PID loop of the iron.

Doesn't matter. These are the terms the people who make the stuff use, and right or wrong, we have to deal with it.

mnem
 

eutectic | juːˈtɛktɪk | Chemistry

adjective
relating to or denoting a mixture of substances (in fixed proportions) that melts and freezes at a single temperature that is lower than the melting points of the separate constituents or of any other mixture of them: "the eutectic mixture melts at 183°C" | "silver and copper form a eutectic system".

noun
a eutectic mixture.
• short for eutectic point.
ORIGIN
late 19th century: from Greek eutēktos ‘easily melting’, from eu ‘well, easily’ + tēkein ‘melt’.

Thank you. You've confirmed that we all know what the dictionary meaning of the word is; I never argued that, only that this is the term used in particular for a whole class of solders by the people who make them, whether or not they adhere to that definition exactly.

With that established, do you think we could stop beating me over the head for something someone else did, please...?

mnem
Thanks, luvya, buh-bye...