Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 14789196 times)

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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120900 on: May 27, 2022, 08:19:41 pm »
I'd just like to retract my comment I made about Windows 11 not being terrible. It's absolute fucking garbage. I just wasted most of today trying to get a dev environment up on a fresh machine and literally spent the day stepping in cow shit. During the same period I ported the software I was supposed to be working on to .Net Core and it's now compiling and working on my Mac fine :-//. And on that note, I shall mention no more other than if a contract specifies windows from now on it can piss off even if the money is good.

I was considering spending the evening getting the Heathkit counter up but my soul is too crushed so I'm going to sit on my fat arse and F5 ebay all night  :-DD

Just 48H hours ago you told me that you never had problems with Windows, that it always did what you wanted it to do.. and now all of a sudden it's so shiy you won't even take money to work on it, what a change !!!! :-DD


So see, I might not be an IT guru like you but I got to the same conclusion 20 years ago none the less !  >:D

I saw a YT video some guy who ranted about Win11. Basically he explained how with it, MS owned your computer H/W, not you any more. Forgot the details... but it seemed in lien with what every industry is doing more and more in the recent years, so not really surprised...

One more reason to stick to my *Nix machine. I DO own my computer .. been running for 15 years with zero Euro in S/W or licensing or anti-malware anti-virus shit, and it would still run for 10 more years if only I could behave and get myself to have FIrefox running only 30 tabs at all times, instead of 60. This way the 8GB of RAM on the machine would suffice and I would not have to replace the motherboard and all that goes on it...

Geez I sound like a salesman.. but I have nothing to sell, Penguin is free....

To be clear I don't use Windows. This isn't my computer. It's one I have been provided to do some work on. My computer is a (real) Unix machine which is what I was referring to in the initial post :)

As for the penguin, on the server, yeah fine, just about. On the desktop, it's an unholy abomination. Colour management, high DPI, power management is a joke as is any software maturity. It was going well on gnome 2 and then they decided to rewrite everything again...

Win10 1903 is looking a lot less toxic now, inn't it...?  :-DD

mnem
It's okay... we all know he'll flip-flop next week, then flip on his flip-flop again in 'nuther week; that's just bd139's way. ;)

Hell even 21H1 is looking less toxic  :-DD

Variety is the spice of life. Although I'm getting less tolerant of that. I have chucked this turd back in the box and printed a label out to send it back. I'm charging by the hour and they can't afford to give me a windows machine  :-DD

Well so far on the TE front I managed to find the heathkit counter, the plug I need to stick on it and a fuse. But I've lost the bloody screwdrivers now  |O. Had them yesterday so not sure what happened there.
 
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120901 on: May 27, 2022, 08:33:46 pm »

    BWAHAHAHAHA!

Some days, it doesn't take much to remind you how good you've got it. ;)

In OTHER News...



... I am now ready for my authentic Mac experience.  :o

mnem
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120902 on: May 27, 2022, 08:41:16 pm »
ONE OF US. ONE OF US!

Still think that old kit looks better than my new kit  :-DD
 
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Online Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120903 on: May 27, 2022, 09:31:08 pm »
I want to be one of you too, dear gang ! But I can't afford it....

At Uni in Hatfield in the computer room at the library, we had one attached to a superb 21" CRT, served as a Photoshop workstation, dedicated to the A3 Epson flatbed single pass colour scanner attached to it.  You had to book one week in advance to be able to use it, and could only book it for one hour at a time. If you dared monopolizing it for 65 minutes instead of your allocated 60, the guy allocated to the slot following yours, would get mad, asking you to GTFO but you wouldn't, so you would call the security officer to dislodge the recalcitrant bandit. I know, I had to call the officer more than once...
Well, to be fair sometimes others had to call that officer to dislodge me as well  :-//






« Last Edit: May 27, 2022, 09:34:30 pm by Vince »
 
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120904 on: May 27, 2022, 09:39:33 pm »
I think mnem found his dumped on the road side so it's not always expensive!

The grey G3 there ... I never used the old macOS 9 and earlier machines really. They were mostly horrible. Apple only became attractive to me when the early blue G3 turned up and they released macOS X on it. One of our Unix admins bought one immediately and she was very impressed with it because it was a hell of a lot cheaper than buying a Sun machine for home.

Edit: the first mac I used as a dedicated machine only was actually a G4 mac mini. I bought one of them and a 1st gen iPod shuffle. How times have changed.

Went G4 mini -> Intel Core 2 MacBook -> Intel Core 2 MacBook (plastic) -> Intel Core 2 iMac ->  Several Intel macbook pros -> M1 macbook air -> M1 Macbook pro.

Some forks and diversions in there and running thinkpads and PC desktops in parallel as workload required them.
« Last Edit: May 27, 2022, 09:44:01 pm by bd139 »
 
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Offline Neper

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120905 on: May 27, 2022, 09:39:38 pm »
Those were the days. PPC...

Then again, I had the fastest 68k Mac that Apple never built. 68060 at 50 megs.
If I knew everything I'd be starving because no-one could afford me.
 
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Online Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120906 on: May 27, 2022, 09:50:12 pm »
I think mnem found his dumped on the road side so it's not always expensive  :-DD

The grey G3 there ... I never used the old macOS 9 and earlier machines really. They were mostly horrible. Apple only became attractive to me when the early blue G3 turned up and they released macOS X on it.

Funny !  Still at uni, the last year I was there they started installing these "all in one " funky looking transparent G3, and that's precisely what put me off Apple instantly ! Still to this day.

Well of course I know sqaut about the OS side of things under the bonnet, as  a user I didn't care.... a computer is a computer. You click on an icon it loads the S/W...  >:D

But yes from what I understood years later retrospectively, The Unix based OS was introduced with OSX and these funky looking colourful G3, and before that it was AppleOS  xys which I gather was a pile of shit inside, but of course only people like you would know or care about that back then ! >:D
As a user I just loved the old Os on the beige Macs. Well except it took an hour to boot and the mouse had only one button... but well back then we didn't do as much with computers so the loss of "productivity" hardly bothered me....
I don't know if could survive with a single button mouse today, or without a scroll wheel either....
But, I still want at least one old beige Mac for my future retro computer museum/room/corner...and possibly another one that I would just use the tower case of, and restuff with a modern motherboard.
My computer is due to be renewed ina year or so finances allowing, so it might happen sooner rather than later.

 

Online Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120907 on: May 27, 2022, 10:07:53 pm »
2N3055 experiment follow-up.

Checking the datasheet to see what the B-E junction breakdown voltage is.

Says the ABSOLUTE MAXIMUM is 7 Volts. Mine gave up at 15 Volts.

Datasheets are a load of rubbish.

It's all I had to say.

Good night.

 

Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120908 on: May 27, 2022, 10:09:18 pm »
I think mnem found his dumped on the road side so it's not always expensive  :-DD

The grey G3 there ... I never used the old macOS 9 and earlier machines really. They were mostly horrible. Apple only became attractive to me when the early blue G3 turned up and they released macOS X on it.

Funny !  Still at uni, the last year I was there they started installing these "all in one " funky looking transparent G3, and that's precisely what put me off Apple instantly ! Still to this day.

Well of course I know sqaut about the OS side of things under the bonnet, as  a user I didn't care.... a computer is a computer. You click on an icon it loads the S/W...  >:D

But yes from what I understood years later retrospectively, The Unix based OS was introduced with OSX and these funky looking colourful G3, and before that it was AppleOS  xys which I gather was a pile of shit inside, but of course only people like you would know or care about that back then ! >:D
As a user I just loved the old Os on the beige Macs. Well except it took an hour to boot and the mouse had only one button... but well back then we didn't do as much with computers so the loss of "productivity" hardly bothered me....
I don't know if could survive with a single button mouse today, or without a scroll wheel either....
But, I still want at least one old beige Mac for my future retro computer museum/room/corner...and possibly another one that I would just use the tower case of, and restuff with a modern motherboard.
My computer is due to be renewed ina year or so finances allowing, so it might happen sooner rather than later.

If you want a retro mac, best thing you can do is get an old iMac, scoop the insides out and do this (or make a fish tank)  :-DD



To note I'm no collector of retro computers. I've been there. It's another rabbit hole of misery I look back through rose tinted glasses. They are far more obtuse than old bits of test gear, far more common and far more in demand which keeps the prices and the problems at levels of insane I can't justify. Plus after years in the IT trade, I find anything which costs money on that side of things rather than pays it abhorrent  :-DD
 
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120909 on: May 27, 2022, 10:10:01 pm »
2N3055 experiment follow-up.

Checking the datasheet to see what the B-E junction breakdown voltage is.

Says the ABSOLUTE MAXIMUM is 7 Volts. Mine gave up at 15 Volts.

Datasheets are a load of rubbish.

It's all I had to say.

Good night.

Great experiment. Enjoyed watching you light up 2n3055's :D

Datasheet has headroom :)
 
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Online Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120910 on: May 27, 2022, 10:29:05 pm »
I think mnem found his dumped on the road side so it's not always expensive  :-DD

The grey G3 there ... I never used the old macOS 9 and earlier machines really. They were mostly horrible. Apple only became attractive to me when the early blue G3 turned up and they released macOS X on it.

Funny !  Still at uni, the last year I was there they started installing these "all in one " funky looking transparent G3, and that's precisely what put me off Apple instantly ! Still to this day.

Well of course I know sqaut about the OS side of things under the bonnet, as  a user I didn't care.... a computer is a computer. You click on an icon it loads the S/W...  >:D

But yes from what I understood years later retrospectively, The Unix based OS was introduced with OSX and these funky looking colourful G3, and before that it was AppleOS  xys which I gather was a pile of shit inside, but of course only people like you would know or care about that back then ! >:D
As a user I just loved the old Os on the beige Macs. Well except it took an hour to boot and the mouse had only one button... but well back then we didn't do as much with computers so the loss of "productivity" hardly bothered me....
I don't know if could survive with a single button mouse today, or without a scroll wheel either....
But, I still want at least one old beige Mac for my future retro computer museum/room/corner...and possibly another one that I would just use the tower case of, and restuff with a modern motherboard.
My computer is due to be renewed ina year or so finances allowing, so it might happen sooner rather than later.

If you want a retro mac, best thing you can do is get an old iMac, scoop the insides out and do this (or make a fish tank)  :-DD



To note I'm no collector of retro computers. I've been there. It's another rabbit hole of misery I look back through rose tinted glasses. They are far more obtuse than old bits of test gear, far more common and far more in demand which keeps the prices and the problems at levels of insane I can't justify. Plus after years in the IT trade, I find anything which costs money on that side of things rather than pays it abhorrent  :-DD

Yes that's the one we had at Uni when I left ! Ugly as fuck. That's when I gave up on Apple. I only like their old beige stuff. To each their own I guess, it's a personal thing.

Don't intend to dig into the retro computer rabbit hole either. Only an old beige Mac, plus a Bull Micral 30 to remind me of mine, my first computer 30 years ago, miss it. but this one is total unobtainium, it's not even a matter of price. Plus, the whole point as far as I am concerned with old retro stuff is to get cool stuff for dirt cheap. As soon as there is speculation and prices become silly, I instantly lose interest. Either it''s cheap and I find it cool, or it's not and I find it pathetic.

As for performance well it's not like I was wanting to use it as my main computer of course... just play with it every now and then.  It's like TE. When we get vintage hollow-state TE we don't expect it to perform like a 10K brand new Keysight top of the line piece of gear, do we... that does not mean we can't enjoy it for what it is... just like you enjoy the old HP VOM that you just bought and are working on. It's not because you bought one, that you will spend a million buying everyone of them in existence.. You just want one or two, get it going and appreciate it for what it is, not expecting to perform like a fancy modern unit. Same for old computers for me... it's all under control...

As for spending money on them....  yes and no. I would not mind spending some money on them, like.. 50 Euros here, 50 Euros there, because it's a hobby, it's not really a computer anymore. However spending any money on my MAIN / real computer, which is ugly and crap like all modern computers, I hate them all... then yes, the less money and time I spend on it, the better, because I get no joy from using it. It's a necessity to have one to get things done, so I have one, no choice. But the less time I spend fucking with it, the less money it requires from me, the better. That's why I am glad it made it to 15 years of age, 15 years not having to spend money on it nor fuck with it. Installed Ubuntu on it when I got it, from then I simply updated it via internet. Then in 2016 I stopped updating it, even better, even less troubles. As the yanks say, " if it ain't broken don't fix it " !
 :-//
« Last Edit: May 27, 2022, 10:37:22 pm by Vince »
 

Offline nixiefreqq

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120911 on: May 27, 2022, 10:31:49 pm »
2N3055 experiment follow-up.

Checking the datasheet to see what the B-E junction breakdown voltage is.

Says the ABSOLUTE MAXIMUM is 7 Volts. Mine gave up at 15 Volts.

Datasheets are a load of rubbish.

It's all I had to say.

Good night.

hey vince

just wanted to say thanks for the topless entertainment.

free range primate
 
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Online Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120912 on: May 27, 2022, 10:38:33 pm »
I am glad you liked  it, 2 of my 3 2N3055 died for it, have only one left now ! :scared:

 
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Offline BU508A

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120913 on: May 27, 2022, 10:45:30 pm »
2N3055 experiment follow-up.

Checking the datasheet to see what the B-E junction breakdown voltage is.

Says the ABSOLUTE MAXIMUM is 7 Volts. Mine gave up at 15 Volts.

Datasheets are a load of rubbish.

It's all I had to say.

Good night.


ST:TNG - Relics (1992)

[Scotty and Geordi are working to restore the Jenolan's systems]

Scotty : Shunt the deuterium from the main cryo-pump to the auxiliary tank.
Lt. Commander Geordi La Forge : Er, the tank can't withstand that kind of pressure.
Scotty : [laughs]  Where'd you... where'd you get that idea?
Lt. Commander Geordi La Forge : What do you mean, where did I get that idea? It's in the impulse engine specifications.
Scotty : Regulation 42/15 - Pressure Variances on the IRC Tank Storage?
Lt. Commander Geordi La Forge : Yeah.
Scotty : Forget it. I wrote it. A good engineer is always a wee bit conservative, at least on paper. Just bypass the secondary cut-off valve and boost the flow. It'll work.


 ;D
“Chaos is found in greatest abundance wherever order is being sought. It always defeats order, because it is better organized.”            - Terry Pratchett -
 
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Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120914 on: May 27, 2022, 11:24:45 pm »
More prosaically, the 2N3055 has been around so long that it has been 'reimagined' in what must now be 10 generations of semiconductor manufacturing processes. Hell, there probably isn't a fab in existence that's capable of making a genuine original spec 2N3055 in the process it was originally made in. The upshot of this is that if you want to know the actual parameters of a part labelled "2N3055" you need the specific data sheet for the specific variant of the generic 2N3055.

It should come as no surprise then to find a generic 2N3055 emitter base reverse breakdown of 7V and an actual one for the part on hand of more than twice as much. That's way too much of a difference to attribute to "engineer's safety margin fudge factor" but isn't too much for "The actual process for this part is way better than the 2N3055 spec calls for, but we'll just specify the official 2N3055 figures so people don't point to the higher specified figure and think it implies that the part is in some way incompatible.".
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120915 on: May 27, 2022, 11:33:41 pm »
That is very true. In fact if you have old Tektronix 7000 series scopes with the 3055's slapped on the back, you have to use older RCA transistors or add a miller capacitor because the new ones oscillate  :palm:
 
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Offline BU508A

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120916 on: May 27, 2022, 11:48:00 pm »
Motorola 2N3055 with date code 7923 - 13 Euro per piece.  :wtf:

https://www.ebay.de/itm/384721119094



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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120917 on: May 27, 2022, 11:53:41 pm »
Motorola 2N3055 with date code 7923 - 13 Euro per piece.  :wtf:

https://www.ebay.de/itm/384721119094



NAWTS
Worth every penny compared to the muck some try to pass off as a 2N3055 !
Some old stuff pushed their ratings some but try and install modern replacements and they just go tits up.  :rant:
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120918 on: May 28, 2022, 12:00:45 am »
I think mnem found his dumped on the road side so it's not always expensive!

The grey G3 there ... I never used the old macOS 9 and earlier machines really. They were mostly horrible. Apple only became attractive to me when the early blue G3 turned up and they released macOS X on it. One of our Unix admins bought one immediately and she was very impressed with it because it was a hell of a lot cheaper than buying a Sun machine for home.

Edit: the first mac I used as a dedicated machine only was actually a G4 mac mini. I bought one of them and a 1st gen iPod shuffle. How times have changed.

Went G4 mini -> Intel Core 2 MacBook -> Intel Core 2 MacBook (plastic) -> Intel Core 2 iMac ->  Several Intel macbook pros -> M1 macbook air -> M1 Macbook pro.

Some forks and diversions in there and running thinkpads and PC desktops in parallel as workload required them.
      

As I said; I went to the old neighborhood today... while I was driving through, one gentleman was wheeling these to the curb. Needless to say, I stopped immediately and asked if that was really what was in those boxes; the answer was yes, but the hard drives had been removed. I said that was fine, I had a G5 back in the day and this would be a great chance to revisit... but could I please take the sleds off the old drives if he still had them...?

The fellow hemmed & hawed for a minute, then produced a box with 4 750GB Barracuda drives and asked "Are you a computer guy?" I said yes. "Would you please wipe the drives?" "Yeah, no problem!"

I took the box and thanked him, and we were on our way...

https://everymac.com/systems/apple/mac_pro/specs/mac-pro-eight-core-3.0-2008-specs.html

https://everymac.com/monitors/apple/studio_cinema/specs/apple_cinema_display_30.html

Whuf... this one was loaded for storage & graphics; those HDDs were all part of the original build. As were dual Xeon E5472s, 24GB DDR2-800 RAM,  a GeForce 8800GT GPU, and dual GB Ethernet. Huh.

Allright... I've peeked inside the boxes to make sure they didn't contain angry badgers or bobcats; tomorrow after I've had a chance to rest I'll actually unpack and look inside the CPU... mnem  :=\

I didn't even give them a chance to get to the curb!    :-DD   I literally slammed on the brakes as the guy was wheeling them out on a handtruck complete in their boxes... I asked politely first, of course, but I glommed with extreme prejudice and they were in the back of the car in a trice.... not even, more like half a trice!  >:D

I agree; even today I like the looks of my Bionic Cheese Grater and the Man-Eating Cinema Display better than almost anything has come from Cupertino before or since... It is one of those seminal designs; timeless. 50 years from now, when we're jacking in directly and Ono-Sendai really is a household name because of course someone will use it, the most-popular historical archives will point to these as the epitome of "desktop personal computer".

As an aside... today when I got the Apple Magic keyboard, I also picked up a brand-new, still in the clear plastic condom genuine Apple dock... sadly, it is for iPud, not iPod; so for now it's just a desk ornament Post-it holder. I got it for my wife, who still uses a 7th gen 160GB iPod every day for work. She always preferred the interface on it, even when we had iPwns with oodles of storage. :-//

But hey... at least I got to do the "new Apple peel"...  :-DD



The A1314 keyboard is taking quite some getting used to... it isn't exactly "scaled to fit" clunky old dwagon paws.  :o

mnem
Don't you mess with MacDaddy. >:D
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120919 on: May 28, 2022, 12:13:48 am »
Those were the days. PPC...   Then again, I had the fastest 68k Mac that Apple never built. 68060 at 50 megs.

Heh... I glommed a PPC MacBook white back in the day; was missing the original HDD and I didn't have access to another Mac to make a install disk with. So I installed Ubuntu and used it for the first two semesters of my 2nd go-round at Uni. I had a wee bit of a head start on the other students when it came time to clone drives for Filesystems Forensics 101...  :-DD

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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120920 on: May 28, 2022, 12:24:13 am »
I am glad you liked  it, 2 of my 3 2N3055 died for it, have only one left now ! :scared:

*plays a funeral dirge on waxpaper & comb kazoo for all those sacrificed that one might Grok in Fullness...*  >:D

mnem
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120921 on: May 28, 2022, 12:36:46 am »
More prosaically, the 2N3055 has been around so long that it has been 'reimagined' in what must now be 10 generations of semiconductor manufacturing processes. Hell, there probably isn't a fab in existence that's capable of making a genuine original spec 2N3055 in the process it was originally made in. The upshot of this is that if you want to know the actual parameters of a part labelled "2N3055" you need the specific data sheet for the specific variant of the generic 2N3055.

It should come as no surprise then to find a generic 2N3055 emitter base reverse breakdown of 7V and an actual one for the part on hand of more than twice as much. That's way too much of a difference to attribute to "engineer's safety margin fudge factor" but isn't too much for "The actual process for this part is way better than the 2N3055 spec calls for, but we'll just specify the official 2N3055 figures so people don't point to the higher specified figure and think it implies that the part is in some way incompatible.".

Wikipedia actually has a nice little historical overview; a great place to jump off of for some mind-numbing depth-first searches. I recommend one get well-impaired with their favorite intoxicant first. >:D

https://en.wikipedia.org/wiki/2N3055

mnem
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Offline vk6zgo

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120922 on: May 28, 2022, 01:26:54 am »
Wow looks beautiful.. must have cost a fortune to assemble/manufacture !  :scared:

If you like to watch pictures of semiconductor dies, then you should check out Richis Lab.

Here is an example from a Motorola 2N3055 transistor. What I really like about those pictures about power transistors is that one can see the barrier layer, because Richi is driving them in reverse mode and then the B-E diode becomes a Zener.



B-E diode working as a Zener at 300mA:


OK just sacrificed a 2N3055 and tried the same experiment. Doesn't work, die doesn't light up. VERY disappointed !  :-//   :(

Maybe it can't be seen with the naked eye, or it needs a long exposure time to gather sufficient light, or it requires a special version of the 2N3055, I don't know.
All I can say it that it didn't work on my particular transistor, and I now have one less 2N3055, he died for nothing. I am sad now.

I have to correct myself regarding the B-E diode is becoming a Zener. This is only partially true. The main effect is, that the B-E diode is working in avalanche mode. Depending on the materials being used, the produced light can be anything from IR to blue (SiC for example). Richi states, that the light can be visible to the naked eye, but it is mostly very dim. So, if you want to see this effect, it is perhaps a good idea to sit in a dark room for about 10 minutes so your eyes can adapt to the darkness and then try again.

Here is a discussion about the glowing effect of B-E diodes working in avalanche mode:
https://www.eevblog.com/forum/projects/transistors-die-pictures/msg3068740/#msg3068740

Wow, a thread dedicated to the subject, with beautiful pictures at that ! So my little shitty experiment is pointless then !  :(

.. but I did it ANYWAY, because nothing beats doing it YOURSELF, and seeing it with your own eyes !!  >:D

So I sacrificed yet another  2N3055 transistor... this time I took my time to hack saw it, exercising as much care as I could in a hope I would not destroy / damage the pins/bonding wires inside  :-[
So instead of trying to cut the very top of the cap, instead I cut it at the very bottom, because there is much more clearance with the pins, so less chances that the blade might catch them.
Also I removed the blade from the saw frame, and cut on pull, so I could control the blade better. It was a success, for the first time, 4th attempt, I now have a TO3 that survived its convertible top conversion ! 8)

That means I don't need to stick my SMD probes directly onto the die any more, which was hardly reliable and convenient, I experienced...
Now I can just use grabbers to connect to the outside pins, wire that to the power supply, and I have both hands free to play with the controls on the power supply, and hold the camera steady with both hands. It's getting luxurious can't you see ? ! >:D
Thanks to this much better controlled testing environment, I was able to achieve success, look at that !!!  :-DMM  :D

The B-E junction in reverse starts breaking down / conducting at about 15.2 Volts. To get this picture I put 1.2 Amp into it, Voltage rose to 18V or so. I closed the window shutters to make the lab dark. Then opened the shutters half way and noticed the camera could still pick-up the glow, using the highest ISO setting, 6400.

As you can see the glow does not spread across the entirety of the "path" / squiggly line, for some reason I am way too stupid to explain.
Upping the current has zero effect on this " issue " whatsoever. Past one ampere, upping the current does not increase the glow, it stays where it is.  Past 2 amps, suddenly the glow disappeared and was reduced to one single tiny dot in a corner of the die. I thought OK I blew it, too much current, had to happen... but then I lowered the current limit on the power supply and the glow came back ! It's still alive and going, this transistor is a warrior !!!  >:D   Everyone should have a 2N3055 in his life ! ;D

Wow that was a cool and fun experiment ! Everyone should do that !  >:D

Think I will archive the pics and my test results/notes on it, it was that cool.

EDIT : The experiment cost me more than a few TO3 pacakges... cost me also one of my Hirschmann long grabbers ! Package got so hot during the experiment that it badly melted the tip of the insulation of the black grabber !!  |O







2N3055's are indeed tough------I ran over one, years ago, with the big wide tyres on my car.

As I pulled in to the car port at work, I could hear this "clickety, clickety, click," sound, & investigated, finding it embedded in the tyre.
It had been pins up on the ground, so they penetrated the rubber, luckily not enough to cause a leak.

The top took the brunt of becoming "part of the tread", & was badly dented.
Just for fun, I took it inside & tested it------it was normal in all respects!
 
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Offline vk6zgo

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120923 on: May 28, 2022, 01:39:29 am »
Wow, only 800 Euros ?!  :o 

That's freaking cheap !  Last one I saw here in Frog land was 2 years ago and guy wanted 2,500 Euros for it, "as is", not powered up, super crusty and no test fixture.

Still, 800 Euros is way more than I can afford... and I prefer my 575 anyway !!  :box:

If Brexitland was still European I would have seriously considered a road trip for that, and the incurred wrath of SWMBO for purchasing a boat anchor.

If I win Lotto tonight, I will be straight onto the plane for dear old Deutschland!
 
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Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #120924 on: May 28, 2022, 02:58:35 am »
A break from Kraftwerk for some craftwork. BMW might use quite reasonable quality leather on their seats, but the stuff on their key fobs is rubbish. This fob is the same age as the car, and while the seats are almost pristine that horrible little bit of leather off on the right that was holding the enamelled bit of the fob has almost worn through.



(Please excuse the hairy leg, it was just the most convenient backdrop.)

I took the fob apart, dug a bit of thin black leather out of the scraps bag and now I'm sewing it back together. I haven't done this for ages and any calluses I might have had have all gone. I got this far and decided to take a break because my fingers really hurt.

I've probably procrastinated enough. I'd better get back and finish it.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 
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