Test Equipment Anonymous (TEA) group therapy thread

[Zucca]

Marco Reps got a black 3458B 3458A last year from Keysight:

This causes me to lose balance while sitting

[Brumby]

My reaction at the end of that scene was one of: "Ok - now take it out of the oven.  Now."

[Peter_O]

Obviously batronix in DE is listing out Keysight.

https://www.batronix.com/versand/sales/index.html

On the regular product pages it says: "nicht mehr erhältlich" = "not available any more" at all products less those that are under "sales", which seems to be the rest stock.

[tggzzz]

As a kid, I thought we were celebrating that Fawkes had tried to blow up the Houses of Parliament, not the fact that he failed.

The official line, that we celebrate his failure, and the popular view are at variance. I have been known to mutter on recent Nov 5ths "Guido, where are you when your country needs you?".

In the mid-80s in lat October[1] you could buy a full-size cardboard cutout of Margaret Thatcher. It turned heads when people saw it sitting in the passenger seat of my Land Rover.

As we learned as kids...
Remember remenber the 5th of November
Gunpowder treason and plot
I see no reason why gunpowder treason
Should ever be forgot.

[1] Bonfire night is November 5th.

[med6753]

As a kid, I thought we were celebrating that Fawkes had tried to blow up the Houses of Parliament, not the fact that he failed.

The official line, that we celebrate his failure, and the popular view are at variance. I have been known to mutter on recent Nov 5ths "Guido, where are you when your country needs you?".

In the mid-80s in lat October[1] you could buy a full-size cardboard cutout of Margaret Thatcher. It turned heads when people saw it sitting in the passenger seat of my Land Rover.

As we learned as kids...
Remember remenber the 5th of November
Gunpowder treason and plot
I see no reason why gunpowder treason
Should ever be forgot.

[1] Bonfire night is November 5th.

Did you have a crush on the old girl and have the song "Maggie Mae" on continuous loop? 

[McBryce]

As a kid, I thought we were celebrating that Fawkes had tried to blow up the Houses of Parliament, not the fact that he failed.

The official line, that we celebrate his failure, and the popular view are at variance. I have been known to mutter on recent Nov 5ths "Guido, where are you when your country needs you?".

In the mid-80s in lat October[1] you could buy a full-size cardboard cutout of Margaret Thatcher. It turned heads when people saw it sitting in the passenger seat of my Land Rover.

As we learned as kids...
Remember remenber the 5th of November
Gunpowder treason and plot
I see no reason why gunpowder treason
Should ever be forgot.

[1] Bonfire night is November 5th.

Did you have a crush on the old girl and have the song "Maggie Mae" on continuous loop? 

I think "Maggie's Farm" would be a more fitting song.

McBryce.

[Specmaster]

As a kid, I thought we were celebrating that Fawkes had tried to blow up the Houses of Parliament, not the fact that he failed.

The official line, that we celebrate his failure, and the popular view are at variance. I have been known to mutter on recent Nov 5ths "Guido, where are you when your country needs you?".

Now more than ever IMO. 

[tggzzz]

As a kid, I thought we were celebrating that Fawkes had tried to blow up the Houses of Parliament, not the fact that he failed.

The official line, that we celebrate his failure, and the popular view are at variance. I have been known to mutter on recent Nov 5ths "Guido, where are you when your country needs you?".

In the mid-80s in lat October[1] you could buy a full-size cardboard cutout of Margaret Thatcher. It turned heads when people saw it sitting in the passenger seat of my Land Rover.

As we learned as kids...
Remember remenber the 5th of November
Gunpowder treason and plot
I see no reason why gunpowder treason
Should ever be forgot.

[1] Bonfire night is November 5th.

Did you have a crush on the old girl and have the song "Maggie Mae" on continuous loop? 

Absolutely not! I loathed her politics and believe it set the path towards the unpleasant situation we now find ourselves in.

Besides, it would have been "Maggie Mayn't"; one of her famous soundbites was "This lady's not for turning", and she handbagged the EEC saying "no, no, no".

[ch_scr]

For anyone along the 3DP front, some food for thought - how should this be to fit your scope / desk / workstyle?
https://www.printables.com/de/model/180580-oscilliscope-probe-organizer
I like the idea in general, only immediate flaw is it needs flat, free desk space in front of the scope to open the drawers 

[Ice-Tea]

APN62 display seems to have made a full recovery! Thanks for the tips 

[Specmaster]

Good grief, there are some dumbasses around, just seen this video from Big Clive. I think these people must fall into the category that mnementh talks about.

[Ice-Tea]

The dumbasses are the ones putting out those videos, not the ones deciding to have a go IMO.

[BU508A]

Good grief, there are some dumbasses around, just seen this video from Big Clive. I think these people must fall into the category that mnementh talks about.

One of the reasons, why I don't like Mehdi's videos very much. He is sending out the wrong message imo. ("You can get away messing with electricity.")

[Specmaster]

The dumbasses are the ones putting out those videos, not the ones deciding to have a go IMO.

Well, you could argue that both are.

[mnementh]

My reaction at the end of that scene was one of: "Ok - now take it out of the oven.  Now."

I know, right...?
And then he closes that grungy-ass door right on it...   

mnem

[Brumby]

One of the reasons, why I don't like Mehdi's videos very much. He is sending out the wrong message imo. ("You can get away messing with electricity.")

+1   

[m k]

Yeah I hope that's it.  I have just ordered x3 NOS 6AQ5 from Ebay France, so hopefully I shall receive them late next week all going well.

30 Euros shipped. 10 Euros per tube. Not cheap by my wallet standards, but not crazy expensive either, for NOS tubes I mean.

Best deal was 4 NOS ones for 18 Euros shipped, but they come from Ukraine so delivery time, or delivery at all really, is unknown. I don't want to waste 18 Euros down the drain nor wait 3 months to get them 

So hoping to get my tubes late next week then. In the meantime I will resume work on the Rochar Nixie DMM  I think

How fast are your peek hold meters, can't you expect some results from them?

I am really sorry but I don't understand what you mean ?! 
My English is not up to sniff it looks like 

Could you rephrase that please ?

Sorry, my bad.
And a wrong quote but dam, I've never realized I can click the quote header and move to quoted message.

The detailed message was for your earlier oscillator tube circuit capacitor measurement.
My thought was that your scope didn't work or the capacitor is bad.
Your earlier low voltage says that there's no short to ground but reason for later 0V has few options.

Maybe you should do a special peak detector.
My guess is that you'll see similar stuff also in the future.
Yes, I don't trust that scope is (not)triggering if I don't see it.

BTW,
I have 64x M5M41000AL-10 ZIP for P&P.
Can't see all types but it's an original set.
The catch it that they are connected and I'm not very keen to send the whole board, it's quite big and will obviously be hammered to pieces.
I'd rather cut the memory section out and send just that.
Other possibility is that I'm dropping those chips out with hot air but it's a multilayer board and I have no idea how much heat from solder side it needs.

[m k]

An ADG368, an ADG368, my kingdom for an ADG368......


So, dealing with a recalcitrant TDS754D here that apparently lost its cal constants from the EEPROMS (U1052 and U1055) on the acquisition board.
I've had luck replacing them in the past, but this time I can't read or write anything to or from them using the EEPROM/NVRAM read/write utility stuff from somewhere on the forum that I put on floppy disk (It works on another working scope so my disks are good).

I replaced the EEPROMS with brand new ones and then tried writing the cal data from another TDS754D to at least get something force-fed in there but no dice...

So taking a look at the schematic, the EEPROM write control pins are tied to a 74HC86, which receives 5v from the famous 'Write Enable' switch on the processor board, via a 15V to 12V vreg and voltage divider.
All voltages test ok, so I replaced the 74HC86 because it was easy, still no dice. hmmmm.

I have also double checked all traces for continuity, all perfect like the day it was born.

So, the I2C data comes from a 160-pin chip, ADG368. Hmmm, all my spare boards use ADG308 chips. Well, lets get the hot air gun out and swap to see... No boot. Shiet, incompatible.
Swap back and we are booting again but errors are back to square one. So I think the ADG368 chip is most likely the bad bit at this stage (or whatever is feeding the AGD368..) I'll have to scope the I2C lines to the EEPROM chips too, to see if there is activity there.

Now, about finding another ADG368......... 

Last resort, pull good EEPROMS full of cal data from a scrapped TDS754D, stick them in and hope it works, if so, call it good. 
I also want to rig something up to directly read the data from the old EEPROMs to see if they might actually still be good, maybe something is just stopping the disk utility (and hence the scope) from seeing the data.
How can I do that with the bare chips in my hand? I have a bunch of programmers and chip clips etc but I'm not up with writing and reading directly to I2C chips...

Any idea what that 12V does?
My guess is that some version of NVRAM needed it for writing.

[factory]

Good grief, there are some dumbasses around, just seen this video from Big Clive. I think these people must fall into the category that mnementh talks about.

Guessing they don't bother to read the warnings on unit, but the last rusted out one I scrapped, doesn't mentioned anything about death.  Still not found any of those modern high frequency switching transformer versions, guess copper coloured aluminium wire & steel is cheaper. 


I seem to recall someone on the radio forum mentioning a repair training instructor, that died after not discharging the HV capacitor, as Clive said never trust the built in discharge resistor.

David

[mnementh]

As a kid, I thought we were celebrating that Fawkes had tried to blow up the Houses of Parliament, not the fact that he failed.

The official line, that we celebrate his failure, and the popular view are at variance. I have been known to mutter on recent Nov 5ths "Guido, where are you when your country needs you?".

In the mid-80s in lat October[1] you could buy a full-size cardboard cutout of Margaret Thatcher. It turned heads when people saw it sitting in the passenger seat of my Land Rover.

As we learned as kids...
Remember remenber the 5th of November
Gunpowder treason and plot
I see no reason why gunpowder treason
Should ever be forgot.

[1] Bonfire night is November 5th.

Did you have a crush on the old girl and have the song "Maggie Mae" on continuous loop? 

I think "Maggie's Farm" would be a more fitting song.

McBryce.

Ahem. Politics. Y'all demanded zero-tolerance. I've complied.

At least try not to rub it in my face, please.

mnem
Just say "No, thank you."

[Ice-Tea]

The dumbasses are the ones putting out those videos, not the ones deciding to have a go IMO.

Well, you could argue that both are.

Maybe. But isn't the whole point of a tutorial/instruction video that you present yourself as someone who knows better than the target audience?

[mnementh]

The dumbasses are the ones putting out those videos, not the ones deciding to have a go IMO.

Well, you could argue that both are.

Maybe. But isn't the whole point of a tutorial/instruction video that you present yourself as someone who knows better than the target audience?

"They say it's not the volts; it's the amps that kill you."

"How many amps izz THAT...?"

"Enough to cook a fucking turkey from the inside out. It can do the same to your heart."

mnem
"Electrons may be very very tiny, but when they gang up on you, they always win." ~me

[mnementh]

   https://www.printables.com/de/model/180580-oscilliscope-probe-organizer

For anyone along the 3DP front, some food for thought - how should this be to fit your scope / desk / workstyle?

I like the idea in general, only immediate flaw is it needs flat, free desk space in front of the scope to open the drawers 

I've printed numerous add-on drawer things for my printers over the years, and always wound up taking them off. With FDM printing, they just don't run smooth, unless you print them loose enough that they flop all over the place.  Also, the drawer pulls on that one are ridiculously too small to be usable. A quick remix will fix that, of course.



Maybe I've just gotten spoiled by my Ikea MICKE, which I use as a scope cart. When nobody's looking, I do exactly that with the leads in the second drawer, and by having such a long loop reaching down, the cable stays in a nice relaxed curve, so it doesn't want to tangle up at all when I'm using it or when I lay one coiled up on top of the other in the drawer. 

Of course, all the other drawers are perfect to keep all my assorted other probes, tees, adapters and terminators handy and organized too. Oh, and the roller glides are so-o-o-o silky smooth... 



IMHO, for $60 it's really the closest thing to a perfect scope cart you're gonna get, plus it frees up some bench space. I took the extra caster off the middle-front; it's there to provide extra support for the bottom drawer (intended to be a filing cabinet drawer), but for this light duty use it's unnecessary and tends to make the whole thing harder to steer.



Something like that might be tolerable for to zip-tie up under the shelf on scopes set up like this, tho... 




EDIT: Thinking about it, I actually don't believe I'd ever want to abuse my probes by storing the leads coiled up tight enough to fit in those little drawers, so no, I guess... on all counts.   

mnem
 

[med6753]

As a kid, I thought we were celebrating that Fawkes had tried to blow up the Houses of Parliament, not the fact that he failed.

The official line, that we celebrate his failure, and the popular view are at variance. I have been known to mutter on recent Nov 5ths "Guido, where are you when your country needs you?".

In the mid-80s in lat October[1] you could buy a full-size cardboard cutout of Margaret Thatcher. It turned heads when people saw it sitting in the passenger seat of my Land Rover.

As we learned as kids...
Remember remenber the 5th of November
Gunpowder treason and plot
I see no reason why gunpowder treason
Should ever be forgot.

[1] Bonfire night is November 5th.

Did you have a crush on the old girl and have the song "Maggie Mae" on continuous loop? 

I think "Maggie's Farm" would be a more fitting song.

McBryce.

Ahem. Politics. Y'all demanded zero-tolerance. I've complied.

At least try not to rub it in my face, please.

mnem
Just say "No, thank you."

Oh please. No one pissed in your wheaties this morning. Not politics, just good natured ribbing. You need more caffeine and try again. 

[TERRA Operative]

An ADG368, an ADG368, my kingdom for an ADG368......


So, dealing with a recalcitrant TDS754D here that apparently lost its cal constants from the EEPROMS (U1052 and U1055) on the acquisition board.
I've had luck replacing them in the past, but this time I can't read or write anything to or from them using the EEPROM/NVRAM read/write utility stuff from somewhere on the forum that I put on floppy disk (It works on another working scope so my disks are good).

I replaced the EEPROMS with brand new ones and then tried writing the cal data from another TDS754D to at least get something force-fed in there but no dice...

So taking a look at the schematic, the EEPROM write control pins are tied to a 74HC86, which receives 5v from the famous 'Write Enable' switch on the processor board, via a 15V to 12V vreg and voltage divider.
All voltages test ok, so I replaced the 74HC86 because it was easy, still no dice. hmmmm.

I have also double checked all traces for continuity, all perfect like the day it was born.

So, the I2C data comes from a 160-pin chip, ADG368. Hmmm, all my spare boards use ADG308 chips. Well, lets get the hot air gun out and swap to see... No boot. Shiet, incompatible.
Swap back and we are booting again but errors are back to square one. So I think the ADG368 chip is most likely the bad bit at this stage (or whatever is feeding the AGD368..) I'll have to scope the I2C lines to the EEPROM chips too, to see if there is activity there.

Now, about finding another ADG368......... 

Last resort, pull good EEPROMS full of cal data from a scrapped TDS754D, stick them in and hope it works, if so, call it good. 
I also want to rig something up to directly read the data from the old EEPROMs to see if they might actually still be good, maybe something is just stopping the disk utility (and hence the scope) from seeing the data.
How can I do that with the bare chips in my hand? I have a bunch of programmers and chip clips etc but I'm not up with writing and reading directly to I2C chips...

Any idea what that 12V does?
My guess is that some version of NVRAM needed it for writing.

The 12V is brought down to about 5V with a voltage divider to provide 5V to the Write Protect pin on the EEPROMs to put them into write protect mode.
It also goes through some other bits and pieces of logic and ends up connected to the write protect pins on the NVRAM's.