Test Equipment Anonymous (TEA) group therapy thread

[ch_scr]

I was perusing the HPAK E3633A service manual and ran across this:

Surface mount components should only be removed using soldering irons or disordering stations expressly designed for surface mount components.

Emphasis mine.  I think I'll have to get one of those although frankly an anti-disordering station might be more useful.

I think I left mine turned on after using it last time. 
...Certainly would explain the way it looks around here...

[Neomys Sapiens]

Nice Oltronix Triple PSU in UK
www.ebay.co.uk/itm/115046075323
Seller has a single output one too

NAWTS

Did not see this version before. Interesting. Output 4 seems to be unregulated, but metered.

[factory]

Latest accidental acquisition arrived today; Seaward Supernova Elite portable appliance tester (I balk at calling these things PAT testers, for obvious pedantry reasons).

In good working order and with a few calibration and service stickers, just needing flash test probe (readily available) and the earth bond lead (also readily available and easily made).
I didn't really need it (have a half-decent Robin tester), but it was too cheap to not throw a bid, and so I got for just over eighty quid shipped (really expected to get overbid), not bad for an item that retailed at twelve hundred or so before it was discontinued.
It seems to have been used in a production testing environment, and been well cared for, the protective film still on the LCD screen despite its age (probably 12 years or so).

As it's slightly different from our usual fare in this thread, I'll put it near the top of the teardown queue (still, don't hold your breath, work is busy right now).

There is a reason why the leads are missing, the cowboy companies chuck them straight in the bin, this then saves them doing the unnecessary tests and allows them to perform the sticker test straight away. 

Maintenance at work used that Seaward PAT (before the outsourcing to various cowboy firms), one of the operators wasn't very clever, as they had repeated problems with the earth test (has high current function) and ordered a complete new machine, turned out the earth lead was the problem. 
After that the **** that was selling work AVO's, got it on a scrap order as well and sold it for quite a bit on ePay (as needing a new lead), eventually work found out & this has prevented anyone else from buying redundant equipment ever since, the terms of the "scrap order" form are for personal use only.

David

[AVGresponding]

Latest accidental acquisition arrived today; Seaward Supernova Elite portable appliance tester (I balk at calling these things PAT testers, for obvious pedantry reasons).

In good working order and with a few calibration and service stickers, just needing flash test probe (readily available) and the earth bond lead (also readily available and easily made).
I didn't really need it (have a half-decent Robin tester), but it was too cheap to not throw a bid, and so I got for just over eighty quid shipped (really expected to get overbid), not bad for an item that retailed at twelve hundred or so before it was discontinued.
It seems to have been used in a production testing environment, and been well cared for, the protective film still on the LCD screen despite its age (probably 12 years or so).

As it's slightly different from our usual fare in this thread, I'll put it near the top of the teardown queue (still, don't hold your breath, work is busy right now).

There is a reason why the leads are missing, the cowboy companies chuck them straight in the bin, this then saves them doing the unnecessary tests and allows them to perform the sticker test straight away. 

Maintenance at work used that Seaward PAT (before the outsourcing to various cowboy firms), one of the operators wasn't very clever, as they had repeated problems with the earth test (has high current function) and ordered a complete new machine, turned out the earth lead was the problem. 
After that the **** that was selling work AVO's, got it on a scrap order as well and sold it for quite a bit on ePay (as needing a new lead), eventually work found out & this has prevented anyone else from buying redundant equipment ever since, the terms of the "scrap order" form are for personal use only.

David

There's always some knob-head that has to spoil it for everyone else.

The only person I've ever seen doing PAT properly other than myself, was the instructor that taught me... most can't even be bothered to do the visual part properly!

I'll probably buy a flash probe, they aren't horribly expensive, and I prefer a properly insulated one rather than one I can cobble together with HT wire and corona dope.

The earth bond is easy enough, looks to be a standard XLR connector, probably with a 3-core flex with all the conductors in parallel to the croc clip.
Since the maximum current it'll see is 32A (2x 16A on the 110V) I'm comfortable with a 1.0mm² (hell, even 0.75mm² would suffice) flex for this, preferably black rubber insulated. I recently bought some big-assed copper crocs on offer at Rapid, Mueller 40A ones, to fit the boots they sent me in error, and that I got to keep for free once they sent me the correct ones...

[factory]

There's always some knob-head that has to spoil it for everyone else.

The only person I've ever seen doing PAT properly other than myself, was the instructor that taught me... most can't even be bothered to do the visual part properly!

I'll probably buy a flash probe, they aren't horribly expensive, and I prefer a properly insulated one rather than one I can cobble together with HT wire and corona dope.

The earth bond is easy enough, looks to be a standard XLR connector, probably with a 3-core flex with all the conductors in parallel to the croc clip.
Since the maximum current it'll see is 32A (2x 16A on the 110V) I'm comfortable with a 1.0mm² (hell, even 0.75mm² would suffice) flex for this, preferably black rubber insulated. I recently bought some big-assed copper crocs on offer at Rapid, Mueller 40A ones, to fit the boots they sent me in error, and that I got to keep for free once they sent me the correct ones...

Looking through the manual for the Supernova Elite, the specifications state that the earth bond test uses the four wire measurement at 4A, 16A or 25A, probably only needs two wires in the earth bond lead.

Forgot to mention the "new technique" one of the cowboy cow-PAT companies used, it consisted of plugging everything into the bench sockets & the tester into another socket, he then did whatever test gave a quickest pass and gave everything in sight the final sticker test (even the battery operated Beckman 350 DMM), he said this technique saved him a lot of time. 

Unfortunately two out of three companies work have outsourced PAT to (since they stopped in-house testing) have been completely useless, the one company that seemed to be competent, actually brought & used the earth lead, checked fuses and did all the visual checks.  They must have been slightly more expensive, or took too long, as they weren't invited back the next year. 

David

[Vince]

Car stereo update.

I had a go at taking the LCD panel apart to fix the backlight.

2 hours later the stereo is working and all buttoned up, will give it back to my friend tomorrow.

Fixing the LCD went exactly as I hoped it would.... since the backlight logically is... at the very bottom of the "stack", was hoping I could open up the panel from the back rather than the front, so that the first "layer" of the sandwich I would be greeted with, would be the backlight I am interested in, saving me from peeling off all the other layer with the risk of contaminating them with finger prints and dust.

So I was lucky and it happened just like in the above dream. I just undid all the clips around the metallic frame, pried it open gently,  it was cooperating, then the backlight panel was right there for me to pull. LED strip was stuck to the bottom edge of the backlight panel, in some thick white glossy paper doubling as the reflective layer. I instantly saw what I was hoping to see : the black and red wires soldered to the LED strip, and one of them, the black one, had its solder joint separated. So I just soldered it back. However it'(s bound to break again soon given how tiny the solder pad is, and the fact that as soon as the wires exit the strip, they are forced to do a tight 90° turn to follow the corner of the metallic frame of the LCD panel.
Took a couple attempts to manage to squeeze and backlight into the fame and clip everything back, but overall not too bad of a job.

Works fine now... for how long nobody knows. Original failure happened withint the first year, so am not holding my breath !
Also, the entire front panel assembly is "designed" to fail, many stupid choices on how it's put together, that guarantee it will not survive the shocks and vibrations a car endures, especially on the crap roads around here.
I just hope it will last a few months.... crossing fingers... 


Tired 

[Specmaster]

Interesting repair job, well done Vince. Did you think about putting some hot glue on the end of that strip to bond the wire in place and remove most of the vibration getting to the solder pads? 

[mnementh]

For those who care: I recently had a forum member ask aboot a 3DP part for the Datalogging IR Transceiver for the Fluke 87-IV/187/189; in response, I whipped up this quick little universal bracket to fit my Benchtop Meter Stand and updated my post in the Replacement Knobs, Feet and Fittings for Test Equipment thread. It provides a 30mm x 50mm flat plate one can use to attach either the OEM IR Module or your own homebrew module with double-faced foam mounting tape or adhesive-backed Velcro strips. If you look here on eevBlog, there are a number of different such DIY IR transciever projects.

It is bundled together with the correct version of the meter stand in the zip file linked here:

https://www.eevblog.com/forum/testgear/replacement-knobs-feet-and-fittings-for-test-equipment/?action=dlattach;attach=1298407

For strength, both parts should be printed 0.20-0.16LH, laying flat on largest flat surface (back of Meter Stand, front face of IR Adapter bracket), and with infill set to yield a grid pattern with 1-1.5mm spacing. Both parts will print well with no supports.

Cheers!

mnem
*3DP-ily*

[mnementh]

On the bench this morning... fixing it or completely fuxxoring it.

...Next will be to desolder it with my cheap Chinese hot air gun, and if this removes the short, see what happens when I replace that bd139-ified cap and 3.3V regulator to the uPC.

Welp... looks like I mostly fuxxored it. 

After testing the mainboard and the backlight inverter individually to have roughly reasonable current draw and not getting appreciably over-hot for close to 20 minutes, I tried again with the LCD plugged in, then again with the inverter also plugged in. all cases current draw remained in a reasonable 400-500mA range, with 3.3V reg and 1.25VCore reg both within 500mV 50mV of nominal. After this I turned up the CC limit to 1.8A to be able to correctly power the backlight, and since the uPC had not attempted to turn it on, I turned it on by applying my meter in JUNCTION TEST mode across the EN pin.

   

That's when it got... interesting. 




Okay, okay... maybe I shouldn't have lingered with the power applied quite so long trying to get a good smoky shot to post... but I just love you guys, so I had to try. 

Anyhoo... Looking at my parts list, evidently I never wrote this particular one down... nor do I have a single pic where its part number is rendered legibly. DAMMIT!!! I didn't follow one of my cardinal rules; always take lots and lots of high-resolution pics before you start tinkering with shit.

Ah well... later I'll go through my browser history and hope I can figure out what this part was... but right now I need to cook some sghetti for dinner.

mnem
 

[Specmaster]

Wow, that sure did get nice and toasty 

[Zucca]

One minute of silence for mnem who instead to cut the power he shot a pic for us.
You have all my respect.

[med6753]

 

[med6753]

We have these simple and effective devices called "gloves" which are a required Winter wear and prevent numb and cold hands. Perhaps you've heard of them? Yes? No? 

Well Captain Obvious, the thing is that gloves that are thick enough to keep ones hands warm are also too thick to handle a sub-zero steering wheel safely. That's why "driving gloves" are very thin, and that's why driving gloves don't keep one's hands warm.

Obviously......if you had worn gloves while cleaning the snow/ice off the vehicle your hands would not have been cold and numb, would they? 

Wrong, I did wear gloves for that. It was the freezing cold steering wheel that was the problem. What kind of idiot would try to drive off wearing thick wet/icy gloves?

Well gee, call me an idiot then.  The winter gloves I wear provide warmth AND allow me to adequately grip the steering wheel safely.

[mansaxel]

Wrong, I did wear gloves for that. It was the freezing cold steering wheel that was the problem. What kind of idiot would try to drive off wearing thick wet/icy gloves?

Well gee, call me an idiot then.  The winter gloves I wear provide warmth AND allow me to adequately grip the steering wheel safely.

Again, we look at what people who have to be outside in shitty weather while other people are doing their best to kill them use. I wear medium-thick leather gloves as inner layer, and then, depending whether the weather (i had to!) is cold or insanely cold, either a thin leather/cotton mitten or same mitten with a wool inset.



I would be crazy to try driving anything beyond say skiing and snowmobiling wearing those, but clearing the windscreen and the car at large from snow and ice is quite OK. And, I wear the inner gloves all the time. Those, like med wrote, allow me to drive safely, and will be dry and free from snow.

[VK5RC]

Rather bizarrely I love my car's seat heaters - in sth Aus it never gets really cold - my car lives outside 24/7, and as I work in buildings heated to 22C continuously I go to work in a business shirt - gloves? Can't be bothered - the coldest it gets is maybe 5C and work is downhill - maybe 5km so the engine doesn't get hot - God bless the seat heaters! (VW GOLF v7. 5 TDI)
Our old Volvo xc70 had seat fans as well - bloody marvellous for stopping that sweaty arse effect in our summer where it commonly hits high 30s C in summer and the inside of a car probably 10-15 C above that. A sun roof is helpful for initially dumping the hot air. Never had any electrical problems with the seat heaters. ♨️

[AVGresponding]

Looking through the manual for the Supernova Elite, the specifications state that the earth bond test uses the four wire measurement at 4A, 16A or 25A, probably only needs two wires in the earth bond lead.

Forgot to mention the "new technique" one of the cowboy cow-PAT companies used, it consisted of plugging everything into the bench sockets & the tester into another socket, he then did whatever test gave a quickest pass and gave everything in sight the final sticker test (even the battery operated Beckman 350 DMM), he said this technique saved him a lot of time. 

Unfortunately two out of three companies work have outsourced PAT to (since they stopped in-house testing) have been completely useless, the one company that seemed to be competent, actually brought & used the earth lead, checked fuses and did all the visual checks.  They must have been slightly more expensive, or took too long, as they weren't invited back the next year. 

David

A lot of that stems from the fact that they quote silly low per-item prices in order to get contracts with bigger organisations like government and NHS.

The company that does ours allegedly charges £0.35/item, far cheaper than it costs them to have me to do it, hence I only get asked when it's a rush job and the contractor can't, and also on our construction sites where quite often they turn up without PPE and get turned away.

The low price is partly a loss-leader, as they do a number of other maintenance type services for the council, presumably at greater profit margins.

[med6753]

Wrong, I did wear gloves for that. It was the freezing cold steering wheel that was the problem. What kind of idiot would try to drive off wearing thick wet/icy gloves?

Well gee, call me an idiot then.  The winter gloves I wear provide warmth AND allow me to adequately grip the steering wheel safely.

Again, we look at what people who have to be outside in shitty weather while other people are doing their best to kill them use. I wear medium-thick leather gloves as inner layer, and then, depending whether the weather (i had to!) is cold or insanely cold, either a thin leather/cotton mitten or same mitten with a wool inset.



I would be crazy to try driving anything beyond say skiing and snowmobiling wearing those, but clearing the windscreen and the car at large from snow and ice is quite OK. And, I wear the inner gloves all the time. Those, like med wrote, allow me to drive safely, and will be dry and free from snow.

In addition this is required Winter gear. Integrated snow brush/ice scraper. Carry in car at all times and will prevent your gloves from getting wet/icy. I assume they sell these in the UK but perhaps they are incompatible with right hand drive. 

[mansaxel]

The low price is partly a loss-leader, as they do a number of other maintenance type services for the council, presumably at greater profit margins.[/color][/size][/b]

Over here, it's either "installed PC, 1SEK" or "IT consultant, 250SEK/h" which of course wins tenders, and then the inevitable "Oh, you want a screen with that? That'll be 10000 SEK" and "We've run out of cheap conslutants, here is one costing only 1500SEK/h." (Today, a £ is 11,75 SEK)

I had no small satisfaction in writing "Thou shalt achieve cleanliness to IEC 61300-3-35 when fondling fibers" into the installation rules document we use as addendum on all electrical and comms work we contract. And a bunch of other things, like "If you planned badly enough to have to splice en route, we want an OTDR pic of that" and so on and so forth. That'll teach them when they discover it, after winning the tender...

[mansaxel]

In addition this is required Winter gear. Integrated snow brush/ice scraper. Carry in car at all times and will prevent your gloves from getting wet/icy. I assume they sell these in the UK but perhaps they are incompatible with right hand drive. 

Yes, that was a relief to get. It sits lodged under driver's seat all year.

[mansaxel]

Back on topic again!

I did snap a few pictures of the little buck converter, and oh my, is it horrible!

I did improve my measuring setup a bit, and learnt a few things. I was apparently wrong on the switching frequency; it seems there's something going on in the vicinity of 1MHz too.

The first pic, the sawtooth, is after the converter, and at 20mV/div, 1x "probe" (only a BNC cable with croc clips. )

The second pic, the chaos, is before inverter, 50mV/div, same probe.

The setup is very sensitive to handling and probe placement, so getting a good characterisation of the interference does take some measurement skills.  I'm starting to assemble a BOM for taming these. Based on the PDF I posted, I've got some Bourns inductors on the list, but will no doubt have to shop around for more than just those.

[Cerebus]

We have these simple and effective devices called "gloves" which are a required Winter wear and prevent numb and cold hands. Perhaps you've heard of them? Yes? No? 

Well Captain Obvious, the thing is that gloves that are thick enough to keep ones hands warm are also too thick to handle a sub-zero steering wheel safely. That's why "driving gloves" are very thin, and that's why driving gloves don't keep one's hands warm.

Obviously......if you had worn gloves while cleaning the snow/ice off the vehicle your hands would not have been cold and numb, would they? 

Wrong, I did wear gloves for that. It was the freezing cold steering wheel that was the problem. What kind of idiot would try to drive off wearing thick wet/icy gloves?

Well gee, call me an idiot then.  The winter gloves I wear provide warmth AND allow me to adequately grip the steering wheel safely.

O.K.: "You're an idiot!". There, happy now?

Edit: You know, this whole saga of how a quick anecdote on why I decided that a heated steering wheel was not in fact a completely pointless waste of space as I'd originally though turned into you bitching about the completely incidental  precise choices of gloves and tools for car clearing on a cold winter morning might make people suspect that you're a miserable little old anti-social git with nothing better to do than moan at people for no good reason. Oh, hold on, you are.

While we're on the subject, the first present I remember my father buying me, and the first gloves I remember owning, was a pair of boxing gloves.  Just saying... 

[med6753]

We have these simple and effective devices called "gloves" which are a required Winter wear and prevent numb and cold hands. Perhaps you've heard of them? Yes? No? 

Well Captain Obvious, the thing is that gloves that are thick enough to keep ones hands warm are also too thick to handle a sub-zero steering wheel safely. That's why "driving gloves" are very thin, and that's why driving gloves don't keep one's hands warm.

Obviously......if you had worn gloves while cleaning the snow/ice off the vehicle your hands would not have been cold and numb, would they? 

Wrong, I did wear gloves for that. It was the freezing cold steering wheel that was the problem. What kind of idiot would try to drive off wearing thick wet/icy gloves?

Well gee, call me an idiot then.  The winter gloves I wear provide warmth AND allow me to adequately grip the steering wheel safely.

O.K.: "You're an idiot!". There, happy now?

Can you feel the love? 

Here, chill out.

[Cerebus]

Can you feel the love? 

Here, chill out.

I refer the honourable gentleman miserable old scrote to [the edit on] my previous answer. 

[med6753]

Can you feel the love? 

Here, chill out.

I refer the honourable gentleman miserable old scrote to [the edit on] my previous answer. 

Absolutely guilty as charged. I admit it. Now, the other side? 

[Specmaster]

Wrong, I did wear gloves for that. It was the freezing cold steering wheel that was the problem. What kind of idiot would try to drive off wearing thick wet/icy gloves?

Well gee, call me an idiot then.  The winter gloves I wear provide warmth AND allow me to adequately grip the steering wheel safely.

Again, we look at what people who have to be outside in shitty weather while other people are doing their best to kill them use. I wear medium-thick leather gloves as inner layer, and then, depending whether the weather (i had to!) is cold or insanely cold, either a thin leather/cotton mitten or same mitten with a wool inset.



I would be crazy to try driving anything beyond say skiing and snowmobiling wearing those, but clearing the windscreen and the car at large from snow and ice is quite OK. And, I wear the inner gloves all the time. Those, like med wrote, allow me to drive safely, and will be dry and free from snow.

In addition this is required Winter gear. Integrated snow brush/ice scraper. Carry in car at all times and will prevent your gloves from getting wet/icy. I assume they sell these in the UK but perhaps they are incompatible with right hand drive. 

Oh hell yes, they do sell those over here in the UK, they usually appear every year at Lidls before winter sets in, so they should be in store anytime soon. I have one of those in the car (mine has a telescopic handle), I also have a mitten with a built-in ice scraper and I have a long handled brush especially for clearing snow etc from the car roof. Apparently, it is illegal to drive with snow on the roof of your car as it could slide down and block your vision.

I've never known a steering wheel to be so cold that it's either really uncomfortable or dangerous to use unless of course it is made of metal with zero cladding on it, similar to what you would find on old dumpster trucks, newer ones have plastic covering to insulate them and most modern cars have leather covered wheels surely?