Test Equipment Anonymous (TEA) group therapy thread

[med6753]

Smaller 12V fan.   

    BWAHAHAHAHA!

I recognize that fan... I usedta have somewhere around a gross of the fucking things; Dell used 'em in everything desktop for almost 10 years. Have you actually test run the thing in situ...? I ask because I know these are thermally controlled... and once they feel the the heat, they ramp up pretty aggressively. The turbo noise can be quite impressive.

mnem

Yes, that's one of two of the same type of fan you sent me with a bunch of assorted parts a few years ago. I forgot I had it. I haven't installed it yet. Will be getting the separate PSU sorted out with the current fan first.   

[med6753]

You should also see if adding the fan causes the time base to drift and the like. The 7904 was clearly designed to be cooled by convection. The 7904A has a factory fan though.

I did initially have the fan tied into the scope's PSU and the scope circuits did not like it one bit. A bunch of weird issues. And yes, the 7904 is designed to run on convection cooling only but some areas do get very warm. If the fans help to keep the temperatures down then I'm all for it.

Think back to the Type 310A project. That scope was also supposedly designed to run without a fan. The top of the cabinet got so hot that you could potentially burn yourself on it. Tek came out with that under scope fan mount and with it installed the entire unit remained cool.

[McBryce]

Smaller 12V fan.   

    BWAHAHAHAHA!

I recognize that fan... I usedta have somewhere around a gross of the fucking things; Dell used 'em in everything desktop for almost 10 years. Have you actually test run the thing in situ...? I ask because I know these are thermally controlled... and once they feel the the heat, they ramp up pretty aggressively. The turbo noise can be quite impressive.

mnem

Yup, back when you could buy a PC fan that wasn't covered in RGB LED's, turning your PC into a bloody disco.

McBryce.

[BU508A]

Yup, back when you could buy a PC fan that wasn't covered in RGB LED's, turning your PC into a bloody disco.

People have the illusion, that their computer is running faster then.     

[ch_scr]

Yup, back when you could buy a PC fan that wasn't covered in RGB LED's, turning your PC into a bloody disco.

People have the illusion, that their computer is running faster then.     

Some sure do. The others just have to buy them because it's the only ones easily available...
And then they uses these sales figures to tell that people really want them, a lot
*Statistics show if this trend continues, by 2035 the whole of Monaco will be buried under unsold RGB fans completely*

[Saskia]

there are plenty non led fans out there. Send you one ?

[tggzzz]

Sort of TEA related for a change, failed Sprague 109D wet tant  capacitor, rectifier diode is shorted too and the acid that escaped from tant ate the track underneath. 

Had that in my first Tek 1502. Fortunately the PCBs are simple double-sided PCBs, so easily repairable.

[Cerebus]

*Statistics show if this trend continues, by 2035 the whole of Monaco will be buried under unsold RGB fans completely*

Would anybody, other than the actual residents of Monaco, even notice, at least not until it was time for the annual Formula 1 Grand Prix?

[McBryce]

there are plenty non led fans out there. Send you one ?

I was just being sarcastic. However, when I recently ordered a Build to order PC, I had to specify that I didn't want fans with LED's rather than the other way around.

*Statistics show if this trend continues, by 2035 the whole of Monaco will be buried under unsold RGB fans completely*

Would anybody, other than the actual residents of Monaco, even notice, at least not until it was time for the annual Formula 1 Grand Prix?

I would. I go there once a year on (non-F1 related) business.

McBryce.

[vk6zgo]

No, this is too important. This is affects each and every one of us.
I warned clearly that it is an OT: World Events post; you can skip over it if you don't want to read it. But zero-tolerance is just unacceptable.

No, that's not how this works. You either leave the politics off this forum or you'll get banned. Especially when it pollutes existing established threads like this one.
I've deleted your post, please don't do it again.

Aha!--that's why nothing makes sense!

[mansaxel]

*Statistics show if this trend continues, by 2035 the whole of Monaco will be buried under unsold RGB fans completely*

Would anybody, other than the actual residents of Monaco, even notice, at least not until it was time for the annual Formula 1 Grand Prix?

If you opt for the coastal route instead of the autoroute/autostrada when going from Nice to Genoa, yes, you will. I highly recommend this. Not for TE, but for the views. And the nice speed reduction one gets.

[Specmaster]

The 2 Selectest Super 50 meters have arrived, a quick glance over them so far reveals that they are model II and model III, of which the later one will more than likely be a donor for the model II as it has what appears to be a fuber meter movement and has a decent amount of corrosion in the battery dept. :palm

The other one has missing meter reversing switch, apart from that it seems to be a reasonable performer and hopefully the switch from the donor meter should fit it.

Will post photos of them naked when I get around to stripping them down for checking further.

[m k]

Thanks for the detailed explanation. Looked them up in Google Images to see what they actually look like.. then looked at my drawers / stock...

Turns out I have a lot of them ! 

50% of my 14 pin sockets are TI.
90% of my 16 pin sockets are TI.

Oh well.... 

Standard dual leaf type is not much better, it will finally push the chip out.
I've had situations where the chip has been practically not inserted.

Taking a chip out can also bring a leaf out with it.

I'm also quite sure I've seen some chips locked in with a panduit of some sort.
Possibly just an RTC with batteries.

BTW,
I've been donated a floortop, X3400 M3.
Well, at least it doesn't have wheels, and M603 is still a bit taller.

BTW2,
our house has two floors so pre-growing is not a problem.

[SeanB]

Sort of TEA related for a change, failed Sprague 109D wet tant  capacitor, rectifier diode is shorted too and the acid that escaped from tant ate the track underneath. 





David

Rubber sealed tantalum are a replace on sight item, they are guaranteed to fail after a few years, unlike the glass seal versions, which will likely last till the heat death of the universe, or the case corroding through from the outside. I replaced hundreds of them when doing avionics, even the ones fresh in from the stores would be useless and failed, unless brand new. Even Samxcon has a better life, and a much lower price.

[m k]

On the other hand, if you have a 0.75mm² lead for a 2kW heater, the flex becomes just another heating element...   

That would be stupid, so why do that? I still cringe from 13A loads on 1,5mm² because I was brought up on 10A for that cross section.

I tried to check when it has changed here in practice but no luck.
Wall side is still 10A for 1,5mm2.
Can't say how it is with extension cords.

One decades old Schuko/IEC cord had female side molded 6A/250 but male was 10-16/250.

[mnementh]

there are plenty non led fans out there. Send you one ?

I was thinking the same thing:



I never minded a little LED glow to show off a tidy build and quality components; and my preferred color DOES change from time to time.

Ghaaahhh... I remember one build in all amber and another all red... the picture in my mind now just feels like painting the whole thing with mud. 

But I've never been able to stand the blinkenlichten on fans and especially on RAM (seriously, noisy-ass addressable LEDs right on the machine's capacitive-storage memory core) , especially in unicorn blarff colors.

mnem
 

[mnementh]

BTW, I've been donated a floortop, X3400 M3. Well, at least it doesn't have wheels, and M603 is still a bit taller.

BTW2, our house has two floors so pre-growing is not a problem.

Bet you could get DOSDude1's patched-kernel build of MacOS Catalina running on it. 

http://dosdude1.com/catalina/

mnem
Like you don't have enough timesinks in your life already...

[med6753]

Meh....LED's don't bother me. No matter the color. Even the stupid constant changing color display on this little Class D amp which drives the external scanner speaker. I thought about disabling it but I just ignore it, even at night since it's on 24/7. Why they have that built into the amp is beyond me. 

Same with fans. If you own any 500 series Tek's you better get used to them anyway. But since they are large diameter fans they are low frequency and fairly low noise so much more tolerable. There is just one fan that drives me nuts. hp 5248L. That small diameter AC fan is like the sirens from hell. I suppose since it's supposed to be installed in rack it's not that bad. But out on his own on the bench is like finger nails on a chalkboard.  And as far as I know there is no low noise replacement for it.

       

[mnementh]

Yup, back when you could buy a PC fan that wasn't covered in RGB LED's, turning your PC into a bloody disco.

People have the illusion, that their computer is running faster then.     

Some sure do. The others just have to buy them because it's the only ones easily available...
And then they uses these sales figures to tell that people really want them, a lot
*Statistics show if this trend continues, by 2035 the whole of Monaco will be buried under unsold RGB fans completely*

Surely we can trust the Market Anal-ists to tell us the truth about what we want...? 

mnem
*working on perfecting my poker face*

[McBryce]

Yup, back when you could buy a PC fan that wasn't covered in RGB LED's, turning your PC into a bloody disco.

People have the illusion, that their computer is running faster then.     

Some sure do. The others just have to buy them because it's the only ones easily available...
And then they uses these sales figures to tell that people really want them, a lot
*Statistics show if this trend continues, by 2035 the whole of Monaco will be buried under unsold RGB fans completely*

Surely we can trust the Market Anal-ists to tell us the truth about what we want...? 

mnem
*working on perfecting my poker face*

And I didn't even mention the saddest part: I went for a closed-loop watercooled solution for the CPU and it turns out that the copper block (the bit mounted onto the CPU) has an integrated OLED display for absolutely no reason that I can think of?? Why??

McBryce.

[mnementh]

Just gaze into the dragon's eyes, and let the cool blue glow wash all your cares away...

mnem
 

[mnementh]

And I didn't even mention the saddest part: I went for a closed-loop watercooled solution for the CPU and it turns out that the copper block (the bit mounted onto the CPU) has an integrated OLED display for absolutely no reason that I can think of?? Why??

McBryce.

   https://www.eevblog.com/forum/general-computing/$60-all-in-one-cooler-from-amazon-how-bad-can-it-be/msg2621898/#msg2621898

But seriously... there's more than just a copper block in there. Pretty much all sealed AiO (All-in-One) CPU coolers have the pump mounted directly to the copper block; it requires BL motor drive circuitry, so what's the harm in adding a few resistors and LEDs?

I mean, yeah... OLED and Addressable LEDs are ostentatious and full of EMI/RF noise... but again... I do like a little sedate lighting to show off a tidy build.



I'm still undecided on how I feel about the "infinity mirror" effect NZXT included in this AiO I recently acquired "for the inventory"; but for $18 from the Thrift, I'm certainly not going to complain in this case. I can make a custom escutcheon just like I did on the one above and this one for my son:




mnem

[Vince]

2467B... it's all " fixed " !!! 

Can't believe it....

Meant to keep it at that for now, and just button it back up. So before doing that I cleaned the cover, pouch, front panel... because it was all sooooo filthy gooey disgusting.
Removed a sticker as well.

Now is so much better and pleasing to look at and play with, like I bought one 

In the pouch I found ... a lovely user manual in like new condition, as well as a little accordion style user guide  for the 2445/2465/2467 scopes.
AND... a cool little gizmo : a vinyl, foldable Tek blue viewing hood !    Looks so cute. Inside there is a filter to attenuate light reflection for an even better effect.
I gave it a try, works well. The filter is a real improvement as well. I now understand what this red graticule illumination is for.... always found it useless  so far... but it's mandatory when using the hood otherwise you just can't see the graticule, at all.
I shoved my camera into the hood, adjusted the ISO setting by trial and error and eventually you can get quite nice piccies of the screen ! Next to zero light reflection, good contrast... everyone should have one of these ! I am so tired of never being able to take a decent shot of my oscilloscopes when I need to post something here... problem solved then.
But my daily driver is my Fluke / Philips combiscope, so I would need to make a custom hood for this scope... I mean in digital mode it can print a screen capture of course, but in analog mode, obviously not...

So, I et the scope dry a bit, then I powered it up to make sure it survived the washing. It did.
I got then got carried away and played with it some more... and heart attack again : the time base problem arose again :  turning the TB switch on the front panel would modify the readout on the screen but the signal would remain unchanged on the screen !    Plus, this time... it happened on the MAIN time base, not the delayed one ! If the Main time base is fucked as well, scope is useless !

Then.... light bulb time...I finally put all the clues together and came to a happy end : when I looked at the front panel to see what was the frequency thje probe compensation was outputting... to my amazement it did not say "X3 or "Y"... no, it says " 5Hz to 5MHz " !     What the fuck does that mean !!! Does the CPU at power up, generate a random number to decide what frequency it's going to use today ?! 
So... I measured the frequency of the probe calibrator output, using my lovely Metrix Nixie counter. Hell I was not disappointed... the frequency of the compensation signal DOES indeed change as you rotate the Time base knob !
So when you look at the signal with the scope, the signal always looks the same because the scope automatically modifies the frequency of the compensation signal to track the sweep speed ! So overall, it does produce what I was seeing : you change the sweep speed but the freaking signal on the screen does not change ! 

So that's why I could not always reproduce the problem... it only shows when I look at the compensation signal, but of course works fine when I was later feeding the scope with Philips sign gen ! 

Now wonder I was starting to lose it...

So then since I have this nice  user manual, I rushed to see what it would say... and to my surprise it DOES NOT mention any of this, not a hint !! 
I did find mention of it though, but a couple pages further, in a totally unrelated section !  " Timing Check " !

My understanding is that the probe calibration signal is generated using the same time base that's used for the sweep circuitry. So if you want to calibrate the scope time base, instead of feeding the scope with a signal generator and looking at the screen, you can just measure with a counter, like I just did, the frequency the scope puts out on the compensation pin....

So.... in the end I have no time base problem then ?! No fucked up ASIC ?! 



Then, the other big problem, the nasty offsets on Ch1 and Ch2 on most ranges.
In the manual I stumbled upon a page about DC balance.... no adjustment / trimmer on the main board no... this freaking scope can adjust the balance/offsets on its own, like the SPC procedure on a digital Tek scope !!  Just hit the magic key combination to start the procedure, and the scope balanced both channels in a just a few seconds, reporting no error. Simple as that !
I checked all range on both channels, every single range is SPOT ON, even the sensitive 2 and 5mV  / div settings !! 

This scope is as good as new, no problems any more, a winner I am telling you !!! 

So happy I bought it, a good deal ! This scope is a keeper !! 

Obviously all of you out there with a 2465/2467 knew very well all along what my "problems" were, and were laughing in the background instead of rescuing me.

Needless to say, I hate you all deeply !!

I can't believe you let me rot that much for so long. You have no pity, not even for a fellow TEA. I am extremely disappointed.

I feel I need a 6 months TEA abstinence to rethink my membership...

[med6753]

2567B... it's all " fixed " !!! 

Can't believe it....

.......snip

See, you figured it all out and I didn't have to guide you. Plus you did something many don't. RTFM.

Yes, the calibration frequency follows the time base setting and yes, DC Balance is auto set and if working properly is dead nuts.

Welcome to 2465/67 ownership. 

You're welcome. 

[McBryce]

2467B... it's all " fixed " !!! 

Can't believe it....

Well done, you've motivated me just a little further towards tackling my 2465 re-cap. My 2465 has never had anything done to it (no repair, re-cap, RIFA, re-cal), but it works fine at the moment (famous last words).

McBryce.