Test Equipment Anonymous (TEA) group therapy thread

[Vince]

We get weekly "intelligence reports" which are sent out by a dedicated team of internal analysts at work.

OK so we count on you for passing this report every week to us here ! 

For basic parts, Tayda Electronics still have lots of stock however: https://www.taydaelectronics.com/ ... so MMBT2222 $0.03 a go. https://www.taydaelectronics.com/mmbt2222alt1g-npn-general-purpose-transistor-40v-0-6-a.html

Wow, that's the exact same part (ON SEMI ) that I had bought from Farnell. Farnell charged 10 Euros cents, so 12  USD cents.. 4 times as much as Tayda ?!
I got ripped off !! 

Didn't know about Tayda. However not sure how it can be useful since according to their "About US " page, they are from Thailand and the only operation the have in the western world is in the USA... so I would need to import from the US...  so nope 

Well I was not really worried about the trannies anyway. I ordered from Farnell mostly because I get the nice Amphenol DB9 shells/connectors from them, so might as well buy the discrete SMD stuff from them while I am at it. Other Euro Zone alternatives would have been RS or TME.
Don't know if there are any more "big" players in the Euro zone, might well be but those 3 are those I know of...

Toilet paper yeah you stole the words from my mouth !    We made fun of the yanks for stocking toilet paper when there was no need to, creating an artificial shortage, their own misery... but from what you say the "grown ups", big industrial corps are doing exactly the same thing now ! 

[AVGresponding]

Somebody else wanted the 8200A a bit more than me, ah well.

Just unboxed and did a quick check on a non-TE but still moderately interesting purchase. It's a Kenwood DP-J1070, a 100-disc CD player, running 120V 60Hz sadly, but since when have such trivial details bothered folks like us?

Wound the variac to 120V and gave it a tickle; it's alive! And it selects and plays a disc. Not time to check output today, but I can't see that being a problem, it's usually duff lasers or transport failure on stuff like this. Might have to tweak the mains filtering I suppose, good chance I can just swap out the transformer for a 240V one at least.

The cost of this high-mass hi-fi? Obtained it (shipped) for the princely sum of £27.98! Now I just have to try and decide which are my favourite hundred CDs...   

[Cubdriver]

I recently scored a 1975 vintage belt driven Craftsman table saw that needs a little TLC but cuts fine, and a barely used 1978 vintage belt driven 6" jointer/planer for not a lot of money.  Both built like brick sh!thouses.  The guy I bought the saw from, helped me get it off the stand to get it into my van and I had to get help to get it back on the stand as it was too damn heavy for me to lift on my own.   Got the 2 side extensions leveled and most of the rust cleaned off.  Now it is time to figure out how to lube it as space is tight underneath to get to everything.  The interesting thing about both of them is the way the power switches work.  They both have the safety plugs you can remove to render unusable which is not an issue as we are empty nesters but they aren't hard wired.  Both switches have outlets to plug the power cords from the motors.  First time I have seen that.  I love the old stuff, nothing built like it now.  Even my 1940's Montgomery Ward floor standing drill press still works a treat.

How true.  Their older stuff was top notch.  I still have the radial arm saw my father got in the late 60s/early 70s (rarely use it since getting my General cabinet saw, but it still runs great), and a Craftsman bench grinder that he got for Christmas in about 1962.  You can turn it off, come upstairs, grab something from the fridge & return to the garage before it's fully coasted to a stop.  A much newer one that we had at my previous workplace sounded like a worn out cement mixer filled with empty beer cans when it ran.  Total POS.

Like Rat Shack, it hurt to see Sears fail, but they dug their own grave.

-Pat

[Specmaster]

Somebody else wanted the 8200A a bit more than me, ah well.

Just unboxed and did a quick check on a non-TE but still moderately interesting purchase. It's a Kenwood DP-J1070, a 100-disc CD player, running 120V 60Hz sadly, but since when have such trivial details bothered folks like us?

Wound the variac to 120V and gave it a tickle; it's alive! And it selects and plays a disc. Not time to check output today, but I can't see that being a problem, it's usually duff lasers or transport failure on stuff like this. Might have to tweak the mains filtering I suppose, good chance I can just swap out the transformer for a 240V one at least.

The cost of this high-mass hi-fi? Obtained it (shipped) for the princely sum of £27.98! Now I just have to try and decide which are my favourite hundred CDs...   

Yep, I sure did want it a bit more than you did, ain't I a stinker  OK who am I kidding, it wouldn't fit in with my setup so nah, but I am surprised that it went for so much though.

[bd139]

We get weekly "intelligence reports" which are sent out by a dedicated team of internal analysts at work.

OK so we count on you for passing this report every week to us here ! 

Most of it's not very interesting. Belarus about to go bananas. Crypto going to crash soon. Something something North Korea.

For basic parts, Tayda Electronics still have lots of stock however: https://www.taydaelectronics.com/ ... so MMBT2222 $0.03 a go. https://www.taydaelectronics.com/mmbt2222alt1g-npn-general-purpose-transistor-40v-0-6-a.html

Wow, that's the exact same part (ON SEMI ) that I had bought from Farnell. Farnell charged 10 Euros cents, so 12  USD cents.. 4 times as much as Tayda ?!
I got ripped off !! 

Didn't know about Tayda. However not sure how it can be useful since according to their "About US " page, they are from Thailand and the only operation the have in the western world is in the USA... so I would need to import from the US...  so nope 

Well I was not really worried about the trannies anyway. I ordered from Farnell mostly because I get the nice Amphenol DB9 shells/connectors from them, so might as well buy the discrete SMD stuff from them while I am at it. Other Euro Zone alternatives would have been RS or TME.
Don't know if there are any more "big" players in the Euro zone, might well be but those 3 are those I know of...

Toilet paper yeah you stole the words from my mouth !    We made fun of the yanks for stocking toilet paper when there was no need to, creating an artificial shortage, their own misery... but from what you say the "grown ups", big industrial corps are doing exactly the same thing now ! 

Tayda are generally quite good. They ship from Thailand to UK and they never screw an order up. Also they preprint $7 commercial samples on all packages even if there's $100 of crap in them so they seem to mysteriously never get caught by customs and charged for if sent surface mail then . They also sell Royal Ohm 1% 0.25W metal film TH resistors which are my goto for prototyping. CPC also sell those but if you need to top up say 10-20 of each value it works out cheaper to get them shipped from Thailand rather than have to buy in 50 off quantities.

TME were my number one choice for larger orders. Reichelt are pretty good I understand as well https://www.reichelt.com/ . Neither of them ship to the UK any more though 

We have bitsbox in the UK who are quite good but the quality of the parts somewhat varies. They sell in very low quantities though and will quite happily ship one resistor in a bag if you want it https://www.bitsbox.co.uk/

[Cerebus]

Sad....

https://apnews.com/article/rolling-stones-charlie-watts-died-c9551b21e2806b679bd0eeec0bb4ef2b

It's deeply unfair that the only one of the Stones who has treated their body with reasonable respect, the "clean" one, is the first to drop.

I was at Ronnie Wood's Mum's 80th birthday party (his brother Art used to drink in the same boozer as me and he dragged me along for moral support) and Ronnie's idea of 'light refreshment' suitable to an old lady's 80th was to stick several bottles of vodka in the freezer! As for Keef, well, I hardly need to say anything do I?

[med6753]

The Type 547 has been running pretty much all afternoon without a hitch. Powered it down/up several times. If all goes well tomorrow I'll fix the horizontal issue. Then more burn-in the rest of the day. If that goes well then Thursday I will rebuild the final vertical amplifier. Then more burn-in. Once I'm convinced I have all issues fixed then I'll replace (again) the cathode resistors in the +100V supply as well as I did order and receive 2 more 6080 regulator tubes. Then more burn-in with the internal +100V supply.

If all that passes, maybe, just maybe, I can finally perform compensation/calibration. Fingers crossed. 

[med6753]

Sad....

https://apnews.com/article/rolling-stones-charlie-watts-died-c9551b21e2806b679bd0eeec0bb4ef2b

It's deeply unfair that the only one of the Stones who has treated their body with reasonable respect, the "clean" one, is the first to drop.

I was at Ronnie Wood's Mum's 80th birthday party (his brother Art used to drink in the same boozer as me and he dragged me along for moral support) and Ronnie's idea of 'light refreshment' suitable to an old lady's 80th was to stick several bottles of vodka in the freezer! As for Keef, well, I hardly need to say anything do I?

Apparently he had some medical issues several months back and if you read into it the big "C" word hits you in the face.

Did you ever get to meet Mick and the rest of them?

[Cerebus]

Sad....

https://apnews.com/article/rolling-stones-charlie-watts-died-c9551b21e2806b679bd0eeec0bb4ef2b

It's deeply unfair that the only one of the Stones who has treated their body with reasonable respect, the "clean" one, is the first to drop.

I was at Ronnie Wood's Mum's 80th birthday party (his brother Art used to drink in the same boozer as me and he dragged me along for moral support) and Ronnie's idea of 'light refreshment' suitable to an old lady's 80th was to stick several bottles of vodka in the freezer! As for Keef, well, I hardly need to say anything do I?

Apparently he had some medical issues several months back and if you read into it the big "C" word hits you in the face.

Did you ever get to meet Mick and the rest of them?

Na, just Ronnie and his missus. (And brother and mum for obvious reasons.)

[Vince]

Just done soldering the 8 boards my friend ordered. didn't take all that long after all...

Tried different techniques... first used (tacky) flux to hold the components into place while soldering. Kinda worked but hard to dose the stuff using my big 30cc syringe, and time consuming. Plus the stuff expired 3 years ago so it turns into kinda glue. Once heated/soldered it's a huge dark brown sticky mess that even my powerful dedicated chemical can't really clean perfectly. Board still remains a bit sticky afterwards... so I gave that up.  With fresh flux, in a smaller syringe, or a flux pen maybe (have one but can't find it and even if I did it's even older than my syringe...), maybe it could work, dunno.

So next I tried putting a dab of solder on one single pad, soldering it while holding it flat onto the PCB with the tweezers, then soldering the other pad. Kinda works for the MELF diode and 1206 resistors, but the SOT23 trannies have wayyy smaller terminals and the pads are ridiculously tiny, minuscule, so doesn't work. Plus, even on the resistors and diode I would still feel the need to reflow with the hot air soldering station (crappy cheap 858D+ , but does the job...) to make the joints look better and be sure the components were well in place and that there was no tension/stress on the joints.

So then I tried third method : since I reflowed everything, might as well solder everything directly that way ! The less thermal stress on the components, the better.  So I put a bit of solder on every pad using my regular soldering iron and my smallest solder (0.38mm diameter). Pads of the SOT23 are so small you can barely put solder to them, it's ridiculous.

Then I placed all the components at once, very roughly, next to the solder pads. Can't put them ON the pads anyway, because of the solder blobs. Components just can't stay in place on blobs, they just slide around.

Then I just go over each component one by one with the hot air gun, holding the components with the tweezers. Airflow set low, 3 out of 8, to try and not blow the components...
Temperature set to 350°C because I don't know any better, so had to start somewhere.

Soon ran into a problem : board is so tiny that once you have soldered the first component, it keeps the solder liquid until you get to the 4th component at least... I was soldering the 4th component, and accidentally hit the first component with the tweezers... component MOVED ! Its solder still had not solidified !   
So I laid the PCB onto a soaking wet sponge to keep it cool as I solder, and let a second or two pass between each component. Helped a lot.

First board, looked like the resistors looked a bit "cooked"/overheated...oops...

So I lowered temperature a bit, to 325°C, and also lowered the air flow a bit as well as I would still blow components every now and then. Set it to 2.5 / 8.
Seemed to yield better results, no cooking anymore.

How hot do you adjust your hot air station for small components and low thermal mass boards like this ??

Anyway. Next time might try ordering a stencil and some solder paste to see how that goes. Maybe build a little DIY reflow oven, unless the chinese by now have come up with a ready made affordable one ??

Of course getting JLC to solder for me is just as good...

Once done I did some testing. Checked all resistors. All fine at 10K.
Checked all diodes and trannies.. all fine except for one diode that read fine in forward, but read crap in reverse : 2.2V instead of 0.6V... because it's in reverse parallel with the base-emitter junction of one of the tranny (to protect it from large negative voltages from the RS232 serial port). Reflowed tranny, problem solved, was a bad joint.


Question : anybody has a link on the interweb for decent yet affordable tweezers ? Mine are crap. Tips too coarse for SMD stuff, was a pain to use here. Plus although they are made of stainless steel (I think... looks like it), they might as well be made out of butter : they bend so easily that they are now completely out of shape and any and all attempts to straighten them with pliers, failed miserably.  Now even if I press them hard to grab say a thin mod wire.. wire will slip ! Can't even get a hold on that ! 

So need tweezers with finer/sharper tips, and that don't bend too easily...

Any suggestion / link welcome ! What do you have that works ?! 

Also, bench top is made of OSB but it's not very suitable for SMD work... the irregularities of the OSB surface are enough for the SMD parts to hide into !  Once lost, never to be found again !   Plus it gets dirty and then impossible to clean.

So I would like one of these fancy mats that everybody seems to have now.. "cutting mat" it's called ? The large mat that's blue or grey or green, with a grid on it and other stuff... where can I get a good one ? I mean that can stand the heat of a solder iron, , and with edges that lay flat on the bench, don't like mats (mouse or else) that don't lay perfectly flat on the bench, looks cheap and stuff can get underneath it and hide as well ! 
Would like a large grey one with white grid, if possible, yes I am it choosy I know ! 

[mnementh]

   https://www.amazon.ca/dp/B07WDCMY57/

You want a silicone soldering mat like this one. You can solder directly on it, unlike the cutting mat. you probably ALSO want the cutting mat tho; for general assembly and repair work the silicone mat is too soft and easily cut.

   https://www.amazon.ca/gp/product/B07H1GVCBP

You want ceramic tweezers like these. You can solder directly on them with iron or hot air and they don't stick to the solder or the part, unlike the SS ones.

Both of which I proselytized heavily when I got mine.

Also, you might want to try a different tack for that particular assembly:

   https://www.amazon.ca/Helping-Soldering-Workshop-Non-Slip-Weighted/dp/B07MDKXNPC/

Hold the PCB in a vise, or with alligator "Helping Hands", populate the PCB, then heat from underneath. Works a treat with small boards like this one, and much less likely to knock shit off.

Cheers!

mnem
 

[Vince]

Tayda are generally quite good. They ship from Thailand to UK and they never screw an order up. Also they preprint $7 commercial samples on all packages even if there's $100 of crap in them so they seem to mysteriously never get caught by customs and charged for if sent surface mail then .

Oh.. OK ! Sounds good then, might try them out one day 

They also sell Royal Ohm 1% 0.25W metal film TH resistors which are my goto for prototyping.

"Royal Ohm" ? Is that brand name ? I am not good enough in electronic to be choosy about the brand of a 1/4 W TH resistor I must say ! 
What good about them that noname or other brands don't have, that we can buy from Farnell / RS or else ?

When I had to buy 1206 10K resistors for my little boards, was on Farnell, was so overwhelmed by the just how many there was to choose from, didn't know what to do !     So I just went for Vishay ones because well I gathered it an old respected brand for resistors, and I IIRC they acquired Dale which I think also was a top brand for resistors ages ago... but then even Vishay had zillions of 1206 10K resistors, so I just went for the one Farnell had the most stock of, thinking that must be the default one everyone goes to, so has to be a good default choice when you don't know any better ! Sad I know... but can I do...

CPC also sell those but if you need to top up say 10-20 of each value it works out cheaper to get them shipped from Thailand rather than have to buy in 50 off quantities.

Don't know CPC, who's that ?!    I know I suck sorry BD ! 

Reichelt are pretty good I understand as well https://www.reichelt.com/ . Neither of them ship to the UK any more though 

Oh yeah, I learned about Reichelt just a couple weeks ago !  Met a friend who is a car mechanic near Paris but who also dabbles with electronics. He told me he buys he stuff fro Reichelt. "reich" what I replied ?!     
Had a look at their site, looked more hobbyist oriented than the big names, but was surprised that the prices were very low.. normally hobbyist sites multiply Farnell prices by 5 or 10...
Then another chap, my good friend in Germany, also told me he has been ordering he stuff from Reichelt as well, for 20+ years  !
Well I guess it makes more sense that he knows of Reichelt, since it's a German company.

[Vince]

   https://www.amazon.ca/dp/B07WDCMY57/

You want a silicone soldering mat like this one. You can solder directly on it, unlike the cutting mat. you probably ALSO want the cutting mat tho; for general assembly and repair work the silicone mat is too soft and easily cut.

Ah OK, well in this case I would first a large nice cutting mat.. sorry I was wrong to assume you could solder on them, my bad 
So any particular brand for cutting mats to favour,a place no the interweb to get them ? Or is it just a case of just any one you can find it will do the job, they are all equal quality ?!


   https://www.amazon.ca/gp/product/B07H1GVCBP

You want ceramic tweezers like these. You can solder directly on them with iron or hot air and they don't stick to the solder or the part, unlike the SS ones.

Wow they look fancy ! .. though quite affordable somehow.
Is your link just some random page you pulled, or is it the exact brand you are using yourself ? Don't want to buy random ones and figure out I wasted my money when I receive them and give them a test ride...

[BU508A]

If you are after good quality tools, then I'd recommend the sets from Belzer or Bernstein. Bernstein is a bit cheaper.

Bernstein set

Belzer set

A good choice is also Knipex:
Knipex set

As a birthday gift I got a high-precision super sharp tweezer from Bahco made of Titan.
It is a dream to work with.
Bahco Titan

If you look for something cheap to start with, there are lots of offers.
I'd go after a set in the 20 - 50 Euro segment, for example something like this from May:

May tweezers set

And, as always: NAWTS

HTH

[tggzzz]

Just done soldering the 8 boards my friend ordered. didn't take all that long after all...
...
How hot do you adjust your hot air station for small components and low thermal mass boards like this ??

Anyway. Next time might try ordering a stencil and some solder paste to see how that goes. Maybe build a little DIY reflow oven, unless the chinese by now have come up with a ready made affordable one ??

Techniques I evolved a while ago: https://entertaininghacks.wordpress.com/2015/03/25/assembling-pcbs-with-surface-mount-components/

They have worked for me, but they are by no means the only techniques and certainly not professional.

[Cerebus]

So next I tried putting a dab of solder on one single pad, soldering it while holding it flat onto the PCB with the tweezers, then soldering the other pad. Kinda works for the MELF diode and 1206 resistors, but the SOT23 trannies have wayyy smaller terminals and the pads are ridiculously tiny, minuscule, so doesn't work. Plus, even on the resistors and diode I would still feel the need to reflow with the hot air soldering station (crappy cheap 858D+ , but does the job...) to make the joints look better and be sure the components were well in place and that there was no tension/stress on the joints.

That is about the best way to hand solder SMD, based on my experience. Tin one pad, hold part in place with tweezers and reheat the pad so that you tack the part. Then go around the part and solder each joint. Reflowing with hot air afterward doesn't help in my experience - I have tried it for pretty much the same reasons as you.

Getting good at it is, as with all things, a matter of practice. Oh, and learning to only put just as much solder on as the joint needs. SMD has much less tolerance for over-generous application of solder than does through hole work.

Take a look at this:



The two green boards were reflowed with a stencil and paste. But, due to massive clumsiness on my behalf, I knocked two of the parts off while the solder was still molten. Those two parts I put back on the boards by soldering manually. I defy you to tell which two parts were reworked by hand - there's more difference between the two boards because I used two different solder pastes than there is as a consequence of a bit of manual rework. Does this mean that I am unnaturally talented at this? No. Look at the blue practice board. That was my first attempt at SMD work a bit over a year ago. It's a nightmare. The difference between the two is just a bit of practice. Not even, truthfully, a great deal of practice. The recent purchase of the Optivisor as previously discussed makes it a bit easier, one less thing to concentrate on.

As far as tweezers goes, I'm still using those cheapies in the photo that are bottom price eBay specials. At first I blamed them, but in truth it was just learning to control them and the parts that was the issue. I'm sure I'd appreciate a set of super-dooper Lindstroms or similar, but I've found that I don't really need them to stay in control.

If you haven't got enough stuff to practice on, or don't want to risk messing it up until you've reached a minimum level of competence, then get some of those practice boards off eBay. They're cheap and they include components so you won't care about wasting 'good' stuff. get a bit of practice in and you'll wonder what it was you were making a fuss about.

It's the old story - practice, practice, practice.

[mnementh]

There is a shear key in the blade holder on these, but at least with this (possibly cheap aftermarket) blade, it was stronger. This machine is, as I mentioned earlier, mid-1900s engineering. They rely on over-engineered moving parts to keep shit from just exploding.

mnem
 

Don't forget the flywheel key is an integral part of the damage protection mechanism in that it's made of alloy to permit them to shear when the whole lot is brought to an abrupt stop....fair bit of inertia in a flywheel doing 3600rpm.  Yet the blade holder is steel keyed otherwise you'd be replacing it all the time. 

Flywheel nut = 65ft/lbs which for a sideways start motor is also the rewind starter clutch and unless you have the proper tool to fit it just wing it with a set of Stilsons or polygrips  but don't ring it up too tight otherwise the taper won't slip and shear the key next time you use it a Ree-bar cutter. 

Sounds complex but it's a simple and well proven protection system.

Yup. Aware of all of this. I own a pin-spanner socket that would work for torque-wrench on the starter clutch, but that is locked away in the Trailer of Doom in BuffaloNY.

I'm hoping I don't need to be arsed with all that.

mnem
 

   A'aight, tautech... all your gentle admonishments paid off; I actually arsed myself to hammer it mostly flat to throw back on there just long enuf to see if the beast would start. It did, easy as pie on the first pull and just sat there putting at idle. 

Vibration wasn't too bad either, even at WOT, but I decided to stop by Princess Auto on my way back from today's load to the storage and spend the CAD$12 on a new blade, just on GP.

mnem
*moving dwagons*

New blade is quite decent for CAD$12. Balance is dead-on right out the shrink-wrap, and easily 2-3mm thicker than the one that came off. At first I thought maybe it was for garden tractor; but they have a whole different product line of those... and they're even thicker!

Mower starts first pull, runs nice & smooth. I'll need to be more careful from now on. The extra mass of the blade makes pulling the ripcord smooth & easy, almost like one of those old Agway generators with a huge flywheel in the business end. This pleases me very much.

mnem
*moving forward*

[vk6zgo]

"A man made it; a man can fix it." ~grand-dad

mnem
Patience is the cure.

Yes, but what if was "beyond the ken of man", that is, made by a woman?

A woman called "Ken"?

Off-"off topic", but have you noticed how many inanimate objects have the given name "Ken"?

"I need to fix the 'ken Tek7613, so I can use it to fix my 'ken Yaesu FT301."

It even extends to abstract concepts:

"If I don't fix the 'ken radio, I won't be able to do any 'ken ham radio,-----but I can't seem to get the 'ken time!"

[Vince]

Getting good at it is, as with all things, a matter of practice. Oh, and learning to only put just as much solder on as the joint needs. SMD has much less tolerance for over-generous application of solder than does through hole work.

Yes I noticed that ! 
Didn't mention that in my post but it's hard to control the amount of solder I put on the pad, even with my super thin 0.38mm solder.
For the MiniMELF diode it's fine because the terminals are so big (by SMD standards ie...) that I found that you just put as much solder solder as the pad will take, and it will give you the perfect amount. You just can't put too much, no way to screw it up.
However as you can see on my picture, the resistors all had way too much solder    No matter how hard I try to mput very little on the pad, it was always too much, and the resistors end up "riding" on  a huge blob that looks very messy !     Luckily other than looking crap, it still does the job from both from an electrical and mechanical perspective, so not too fussed about it.  That's where a stencil and solder paste might help I think, as you get a controlled and repeatable amount of solder onto the pads. For hand soldering I guess I could improve that by using some flux. Flux pen wold be good I think in that case, need to buy another / fresh one...  At least solder would flow well, spread and make a better looking joint even if it has a bit too much solder.

The two green boards were reflowed with a stencil and paste. But, due to massive clumsiness on my behalf, I knocked two of the parts off while the solder was still molten. Those two parts I put back on the boards by soldering manually. I defy you to tell which two parts were reworked by hand - 

I like a challenge !   ... but the resolution and sharpness of the picture is not good enough, can't examine the joints !  OK I will have to trust you then !

The recent purchase of the Optivisor as previously discussed makes it a bit easier, one less thing to concentrate on.

Bought something similar but I can't work / solder with it, because the working distance is pretty much zero -->  in order to focus, get a neat image, I need to stick the glasses pretty much ON the board, or a inch away from it tops. Can't solder like that...
Plus, being so close to the board means the overhead lighting of the bench can't get to the board, so it's dark.. so I have to stick my nose to the board, hold the board with one hand to bring it to my nose, and with the other hand I grad a torch light to shine some light on the board so I can actually see something... So I can only use it to inspect a board : see where the problems are, rework an area  "blind"/ naked eye, then inspect again to check if what I did fixed it and if the quality of the job is good enough ! Rince and repeat as necessary.... 
A pain. But  still happy I bought them so I can at least inspect traces and joints, and tiny part numbers / markings on SMD stuff...

If you haven't got enough stuff to practice on, or don't want to risk messing it up until you've reached a minimum level of competence, then get some of those practice boards off eBay. They're cheap and they include components so you won't care about wasting 'good' stuff. get a bit of practice in and you'll wonder what it was you were making a fuss about.

Sounds good, will find and buy some !    Plus, I also have boxes full of boards from whatever appliance friends and colleagues bring to me. Some old, some modern  full of SMD including BGA. So I can practice desoldering and soldering stuff on that too.

[xrunner]

If you haven't got enough stuff to practice on, or don't want to risk messing it up until you've reached a minimum level of competence, then get some of those practice boards off eBay. They're cheap and they include components so you won't care about wasting 'good' stuff. get a bit of practice in and you'll wonder what it was you were making a fuss about.

Sounds good, will find and buy some !    Plus, I also have boxes full of boards from whatever appliance friends and colleagues bring to me. Some old, some modern  full of SMD including BGA. So I can practice desoldering and soldering stuff on that too.

Yea Vince I got some of those boards several years ago and got up to speed. Some of them actually do things like flash LEDS, so you can give them away to kids or .... well I shouldn't speak for you - you might like the little blinkin lights for your desk.

 

[Cerebus]

Bought something similar but I can't work / solder with it, because the working distance is pretty much zero -->  in order to focus, get a neat image, I need to stick the glasses pretty much ON the board, or a inch away from it tops. Can't solder like that...
Plus, being so close to the board means the overhead lighting of the bench can't get to the board, so it's dark.. so I have to stick my nose to the board, hold the board with one hand to bring it to my nose, and with the other hand I grad a torch light to shine some light on the board so I can actually see something... So I can only use it to inspect a board : see where the problems are, rework an area  "blind"/ naked eye, then inspect again to check if what I did fixed it and if the quality of the job is good enough ! Rince and repeat as necessary.... 
A pain. But  still happy I bought them so I can at least inspect traces and joints, and tiny part numbers / markings on SMD stuff...

I've got one of the previous generation of these:



Details here at Ikea.

I've been meaning to get another. Makes a great task lamp as the flexible gooseneck lets you put the light exactly where you want it, like this:

[Vince]

That's one hell of a stylish task lamp I must admit !

Now added to my wish list 

[Vince]

Yea Vince I got some of those boards several years ago and got up to speed. Some of them actually do things like flash LEDS, so you can give them away to kids or .... well I shouldn't speak for you - you might like the little blinkin lights for your desk.

 

No I am not into light shows !

Well other than staring in awe for hours at the trace on my old hollow state Tek scopes CRT, as well as my Nixie frequency counters, of course !

[0culus]

I Macgyvered the 4145B some more so I could test it out more.  The ability to overlay measurements is incredibly useful. The curves for the 2N2222A also show hFE.  [edit] and you can use the cursors and lines features to compute the Early voltage.

[bd139]

Bought something similar but I can't work / solder with it, because the working distance is pretty much zero -->  in order to focus, get a neat image, I need to stick the glasses pretty much ON the board, or a inch away from it tops. Can't solder like that...
Plus, being so close to the board means the overhead lighting of the bench can't get to the board, so it's dark.. so I have to stick my nose to the board, hold the board with one hand to bring it to my nose, and with the other hand I grad a torch light to shine some light on the board so I can actually see something... So I can only use it to inspect a board : see where the problems are, rework an area  "blind"/ naked eye, then inspect again to check if what I did fixed it and if the quality of the job is good enough ! Rince and repeat as necessary.... 
A pain. But  still happy I bought them so I can at least inspect traces and joints, and tiny part numbers / markings on SMD stuff...

I've got one of the previous generation of these:



Details here at Ikea.

I've been meaning to get another. Makes a great task lamp as the flexible gooseneck lets you put the light exactly where you want it, like this:

Watch out for them.  That’s where I started. The LEDs go dim very quickly which you don’t notice until you next go to IKEA 

Edit: 6 days off now. Hopefully some TE time in there but got busy holiday schedule stuff