Test Equipment Anonymous (TEA) group therapy thread

[tggzzz]

A rather nice waveform from inside an HP5315, plus an amusing explanation of what it means: https://groups.io/g/HP-Agilent-Keysight-equipment/message/113099

[mansaxel]

I sent them an RMA request. Error description: burst in flames upon initial power on.
This was a brand new Adata SSD ...

This takes dead on arrival to entirely new levels ...

"Lethal on arrival"

 

[SilverSolder]

Great Scott, umm Short !


Put an M2 NVME drive into a Fujitsu Mainboard, turned power on and saw flames.

This is the first time ever that I saw something like that happen ...

I am not going to check the M.2 port if it is still ok ...

The M.2 drive definitely is not. Carbonized ...

Smoke on the Water, Fire in the Sky ...

The Guy Fawkes edition SSD? 

[med6753]

Just as I suspected. The 6800uF capacitors in the Sansui amplifier were glued down with that epoxy that turns corrosive and conductive. It even got all over those little 10uF/50V caps. So now I gotta scrape out all that shit and clean with IPA before installing new. Fun, fun.

Luckily it appears to be the only location in this amp where the epoxy was used.


 

[Saskia]

A rather nice waveform from inside an HP5315, plus an amusing explanation of what it means: https://groups.io/g/HP-Agilent-Keysight-equipment/message/113099

Without having read the explanation
I recognize the foul language of Mordor where ever I see it ...

"Ash nazg durbatulûk, ash nazg gimbatul, ash nazg thrakatulûk, agh burzum-ishi krimpatul"

here:
One Scope to rule them all, One Scope to find them,
One Scope to bring them all and in the darkness bind them

[Saskia]

I sent them an RMA request. Error description: burst in flames upon initial power on.
This was a brand new Adata SSD ...

This takes dead on arrival to entirely new levels ...

"Lethal on arrival"

 

Death from within ...

[Cerebus]

Would an option be to replace the bridge with Shockley's to gain a bit more voltage headroom for a Vreg ?

I think you mean:

Schottky	not	Shockley

Schottky's a bit more compact, it'd be easier to get several  of him on the board. Besides, Shockley was famously cantankerous, I think that the complaining would make you give up even before you got your components placed, let alone soldered.

[bd139]

Going to have to skip Discord this evening. Unfortunately I've got a house full of shite to organise and not much time left to do it in now

[Cerebus]

HP in the 1980s and microprocessors were 1st introduced, brought in a problem tracing solution that involves putting the device into signature mode. Various test points would produce a known digital signal or signature, which when analysed by a 'signature analyzer' and compared against known good or fault codes in the manual would 'simplify' problem solving!
If you are fault tracing one of these vintage TEs they can be helpful - I am not sure how much a modern Salea type device can take it's place.
Rob

Back in the ninetes when we still developed lots of digital circuitry, a colleague championed a project to implement this on our boards. We also had such an analyzer, but the whole thing never took off.
Though I'd really like to know what became of that analyzer ...

I always thought signature analysis was a brilliant idea. The idea of being able to hook up a simple instrument, press 'test' and get a magic number out that when looked up in the service documentation says 'U12 is futzed' or 'A11 and A12 are shorted' is fantastic.

The principle still lives on, just where you can't see it. The BIST on a lot of digital chips uses an on chip signature analyser, sometimes repurposing the access registers for JTAG to get at the signals to build a signature from.

[bd139]

Yep - slightly more modern version of boundary scans.

[med6753]

It ain't perfect but it's much better than before. I made sure the epoxy was completely removed where it coated between jumpers or components. That eliminates any possibly of conductive paths. Installed new capacitors. Going to let amp powered up idle for about a half hour then adjust the bias. Then tomorrow install.


   

[tggzzz]

A rather nice waveform from inside an HP5315, plus an amusing explanation of what it means: https://groups.io/g/HP-Agilent-Keysight-equipment/message/113099

Without having read the explanation
I recognize the foul language of Mordor where ever I see it ...

"Ash nazg durbatulûk, ash nazg gimbatul, ash nazg thrakatulûk, agh burzum-ishi krimpatul"

here:
One Scope to rule them all, One Scope to find them,
One Scope to bring them all and in the darkness bind them

Bear in mind it is an HPAK group. The explanation starts "It is the language of Tektronix scope hoarders, which I will not utter here.  Loosely translated, it reads, ..." where the ... is more TEA-related than your translation.

[med6753]

A rather nice waveform from inside an HP5315, plus an amusing explanation of what it means: https://groups.io/g/HP-Agilent-Keysight-equipment/message/113099

Without having read the explanation
I recognize the foul language of Mordor where ever I see it ...

"Ash nazg durbatulûk, ash nazg gimbatul, ash nazg thrakatulûk, agh burzum-ishi krimpatul"

here:
One Scope to rule them all, One Scope to find them,
One Scope to bring them all and in the darkness bind them

Bear in mind it is an HPAK group. The explanation starts "It is the language of Tektronix scope hoarders, which I will not utter here.  Loosely translated, it reads, ..." where the ... is more TEA-related than your translation.

I'm a Tek Hoarder and I have no clue as to what is going on here. 

Maybe I don't want to know. 

[Cerebus]

[Sings] "There's a guy works down the chip shop swears he's Elvish..."

[Wolfgang]

It ain't perfect but it's much better than before. I made sure the epoxy was completely removed where it coated between jumpers or components. That eliminates any possibly of conductive paths. Installed new capacitors. Going to let amp powered up idle for about a half hour then adjust the bias. Then tomorrow install.

I cant help it but commercial audio stuff always looks like gook inside, especially when compared to T&M stuff from a good company. The only exception is Revox, but that is long ago. Dangling parts on the PCB, rats nest wiring all over the place, brown cardboard PCBs ... Yuck.
Where are the good old days ...

[AVGresponding]

[Sings] "There's a guy works down the chip shop swears he's Elvish..."

But he's a liar,

And I'm not sure about you   

[med6753]

I remain blissfully ignorant. I think it's better that way. 

Anyway, the Sansui amp is done for now. The bias on both channels set to the spec 3.0mV/channel and is rock steady. I did some checking as to the availability of parts just in case we have magic smoke. The outputs are pair 2SC2581/2SA1106 and can be substituted with NTE36 and NTE37. The STK3082 is available as OEM plus NTE1339. That takes care of the unique parts and everything else (except the transformer) is off the shelf replacements.

[med6753]

I cant help it but commercial audio stuff always looks like gook inside, especially when compared to T&M stuff from a good company. The only exception is Revox, but that is long ago. Dangling parts on the PCB, rats nest wiring all over the place, brown cardboard PCBs ... Yuck.
Where are the good old days ...

Agreed, but at least the bottom panel can be removed and it's completely serviceable. Today's audio trash is anything but. If you watch some of the you tube videos the guys who service this stuff either as a living or a hobby hate working on the modern stuff because in most cases you have to completely disassemble the unit to gain access to the bottom side of the circuit boards. 

[mnementh]

A rather nice waveform from inside an HP5315, plus an amusing explanation of what it means: https://groups.io/g/HP-Agilent-Keysight-equipment/message/113099

Without having read the explanation   I recognize the foul language of Mordor where ever I see it ...

"Ash nazg durbatulûk, ash nazg gimbatul, ash nazg thrakatulûk, agh burzum-ishi krimpatul"

here:
One Scope to rule them all, One Scope to find them,
One Scope to bring them all and in the darkness bind them

Bear in mind it is an HPAK group. The explanation starts "It is the language of Tektronix scope hoarders, which I will not utter here.  Loosely translated, it reads, ..." where the ... is more TEA-related than your translation.

I'm a Tek Hoarder and I have no clue as to what is going on here.     Maybe I don't want to know. 

This whole exchange makes me wonder... is there some genetic tendency to loathe clicking on links in a post... or perhaps tendency towards selective blindness that one does not see them at all... which is endemic to the specific breed of geek who frequent these sorts of technically-oriented user groups?

This is by far not the first time I've seen multiple posts and exchanges speculating on the content of something... which is instantly clarified by clicking on a link provided with that thing people are speculating on...

IME, this affliction seems to strike the species of geek/nerd/born with the knack user who frequent memespaces like eevBlog with unerring accuracy.

mnem
 

[capt bullshot]

I cant help it but commercial audio stuff always looks like gook inside, especially when compared to T&M stuff from a good company. The only exception is Revox, but that is long ago. Dangling parts on the PCB, rats nest wiring all over the place, brown cardboard PCBs ... Yuck.
Where are the good old days ...

All the audio stuff I remember from the good old days looks like this. I gave away (or scrapped) most of mine, kept only speakers and amplifiers.

[mnementh]

I cant help it but commercial audio stuff always looks like gook inside, especially when compared to T&M stuff from a good company. The only exception is Revox, but that is long ago. Dangling parts on the PCB, rats nest wiring all over the place, brown cardboard PCBs ... Yuck.
Where are the good old days ...

Agreed, but at least the bottom panel can be removed and it's completely serviceable. Today's audio trash is anything but. If you watch some of the you tube videos the guys who service this stuff either as a living or a hobby hate working on the modern stuff because in most cases you have to completely disassemble the unit to gain access to the bottom side of the circuit boards.

That is precisely why I got out of the recycled electronics trade. Usedta be you could make a living flipping consumer electronics at the flea or fleaBay/Craigslist... it was my primary business when I met my wife in a online chatroom. Nowadays everything is built such that the core sections of the device (amp & PSU sections) which usually need attention are at the bottom of a Jenga-esque pyramid of other shit you must dismantle to get to those core systems. 

A PSU/rail recap which would take 30 minutes on a civilized bit of equipment with a removable bottom cover takes 3 hours; there's simply no profit margin in that unless you're only doing it to keep yourself occupied.

mnem
tzzzt.

[0culus]

I should be able to join discord for a bit today. Time to get the 7904 patient back on the bench and start identifying all the tants I can locate with the help of my new printed service manual (I can actually read the board photos...imagine that!)

[mnementh]

I cant help it but commercial audio stuff always looks like gook inside, especially when compared to T&M stuff from a good company. The only exception is Revox, but that is long ago. Dangling parts on the PCB, rats nest wiring all over the place, brown cardboard PCBs ... Yuck.
Where are the good old days ...

All the audio stuff I remember from the good old days looks like this. I gave away (or scrapped) most of mine, kept only speakers and amplifiers.

   

I collect it like some people collect fine wine. Or like med collects hollow-state. 

mnem
 

[med6753]

A rather nice waveform from inside an HP5315, plus an amusing explanation of what it means: https://groups.io/g/HP-Agilent-Keysight-equipment/message/113099

Without having read the explanation   I recognize the foul language of Mordor where ever I see it ...

"Ash nazg durbatulûk, ash nazg gimbatul, ash nazg thrakatulûk, agh burzum-ishi krimpatul"

here:
One Scope to rule them all, One Scope to find them,
One Scope to bring them all and in the darkness bind them

Bear in mind it is an HPAK group. The explanation starts "It is the language of Tektronix scope hoarders, which I will not utter here.  Loosely translated, it reads, ..." where the ... is more TEA-related than your translation.

I'm a Tek Hoarder and I have no clue as to what is going on here.     Maybe I don't want to know. 

This whole exchange makes me wonder... is there some genetic tendency to loathe clicking on links in a post... or perhaps tendency towards selective blindness that one does not see them at all... which is endemic to the specific breed of geek who frequent these sorts of technically-oriented user groups?

This is by far not the first time I've seen multiple posts and exchanges speculating on the content of something... which is instantly clarified by clicking on a link provided with that thing people are speculating on...

IME, this affliction seems to strike the species of geek/nerd/born with the knack user who frequent memespaces like eevBlog with unerring accuracy.

mnem
 

Maybe I'm just too fucking busy or lazy, take your choice, to read through 75 posts to catch the meaning that really holds no interest to me and I won't get that part of my life back. 

[BU508A]

Saskia is referring to J.R.R. Tolkien - Lord of the Rings.
There is a poem and in this poem there are these lines:

One Ring to rule them all, One Ring to find them,
One Ring to bring them all, and in the darkness bind them,



Source: http://tolkiengateway.net/wiki/Ring_Verse