Test Equipment Anonymous (TEA) group therapy thread

[med6753]

Med, are you really poking the HV innards of that scope with a 1x probe ?
The additional capacitive loading in 1x certainly could be effecting the stability of the circuitry and giving you false info.

Nope, 10X probe. I did not change the settings on the scope.

Ah OK all good then. 

So showing 1x input attenuation was just a test to see if we were being observant enough ? 

Wasn't my intention just didn't bother. If the sweep went intermittent it bounces all around so if that occurred (it didn't today) I was simply looking for a waveform that was unstable. That would have been the smoking gun. Besides...it's near impossible to put anything past you guys. 

In meantime I have disconnected the Siglent and done several power ups. That is when the fail is most likely to occur. So far, rock steady. Did that trimmer adjustment fix it? The jury is still out. I'll give it a few more days before declaring victory. 

[mnementh]

Oh dear. The weakness of my will is only to apparent.

I couldn't resist this diddy scope for £36+shipping - my second (and probably last) thing made by Sinclair/Thurlby.

Let's hope the trace still works when it arrives.   

To me, that thing smells like a junction tester looking for a place to happen. 

mnem
 

[med6753]

Oh dear. The weakness of my will is only to apparent.

I couldn't resist this diddy scope for £36+shipping - my second (and probably last) thing made by Sinclair/Thurlby.

Let's hope the trace still works when it arrives.   

To me, that thing smells like a junction tester looking for a place to happen. 

mnem
 

Non Linear Systems mini scope here. (No, not interested)

https://www.ebay.com/itm/174964350030?epid=2308371335&_trkparms=ispr%3D1&hash=item28bcb01c4e:g:gIQAAOSwZm9hV4sW&amdata=enc%3AAQAGAAACoPYe5NmHp%252B2JMhMi7yxGiTJkPrKr5t53CooMSQt2orsSDAeS9EQtjPGVfKXTxF0%252Bjko2uh0%252Bang5F2n2uels8kmqpDjdzWWJozzIk7XnZm4aMdA8qIuz55ujmUnyh%252BcB4EeblSiff6Hba%252BxCOGn4ieaaiVzT%252BJCgDgZlLJNNdKk9vbXzqkO4aubCiDThP8MYJw%252B3x2gNCqDkSww40AIigbU%252B90%252FD%252FR6j49WP%252FA0CCHo0znwooIuzRBu2fIX8Z%252F3Cy2BeurnEtQ8xz6P4kzQFo8ZyIhKLQ8XUpWIrxyPYzVqmpY52MeNYtketG1CsXsumA7JvrAFQVHbrKXJz2SoMQ0V%252F2MQGVgr%252Flf%252BYcydKSnP2PXOGruzW7bm5iLPUhjwEWJ1mZMFoI5HSWBQLv1a0mytmKd4gzHil3%252Bdk2%252FzzX%252Bd0VgBHvd%252FxeoWsXRfky3qEk9wv9Np22371%252FpHI8d51UGcSkc4RLozollV05jbLWiL3Noc%252BEhs%252BycZs0LqX0iLG6EZEV%252B6B2Q6Oo92Fu4MFsYkIPPC1gbMkEujRXM9MHEj5TFXfmFse2nmIWPqLBUZqhHNCrPxx6vFoR0dQniOJPAHdoSSEM6lWdZLUyT%252FYhNvxRPbYN9MtKVGkmsEmZUuCYJdrDQih6bS6ie6pb42YmtVMJrpsR7URhMfpkTtLjhtmSlrZjAF1sFvcjraTrmHhOw%252BXqFayWCoPCgnx0%252BaVpIQU7Wl1tznGMPKiRuon1tGIte2mcnyQXxLIoBYFG3JX0xB%252FnescD4kGD%252Fn4H%252FDxV5vkxaBaao1GfHot41DjiTkiXB%252BzKNHVQGn%252B3jlC6GtdaiQyUdgeyCBu0c%252BzfJKufMpuZDoPHLB%252FNJ602MN2Bc4K0hd3QXOipPy%252FglqFuLOY8Q%253D%253D%7Campid%3APL_CLK%7Cclp%3A2334524

[mnementh]

On Keto no carbs. No bread, no noodles, potatoes, rice, cake, candy, soft drinks, fruit juice, nothing with high fructose corn sirup, ...

Actually, when on Keto, you need to cut down on anything containing carbs and religiously observe your daily intake limits.

Today I probably got bumped out of Ketosis. Also, I am wolfishly hungry after all that runnin for the past couple of weeks.

I've been putting the squeeze on the last couple weeks before I take a day off for my son's birthday party. Targeting 15 grams/1500kcal; have dipped up to 1700 a couple times but generally managing withoot too much misery.

We'll see if I can keep that pace after la fête d'anniversaire...

Today, definitely burned some calories... boi and I spent a solid 8 hours today doing yard chores. I hurt in places I didn't know I had to hurt in.

mnem
...but I know I'm not gonna have any trouble getting to sleep tonight.

[mnementh]

Med, are you really poking the HV innards of that scope with a 1x probe ?
The additional capacitive loading in 1x certainly could be effecting the stability of the circuitry and giving you false info.

Nope, 10X probe. I did not change the settings on the scope.

Ah OK all good then. 

So showing 1x input attenuation was just a test to see if we were being observant enough ? 

Wasn't my intention just didn't bother. If the sweep went intermittent it bounces all around so if that occurred (it didn't today) I was simply looking for a waveform that was unstable. That would have been the smoking gun. Besides...it's near impossible to put anything past you guys. 

In meantime I have disconnected the Siglent and done several power ups. That is when the fail is most likely to occur. So far, rock steady. Did that trimmer adjustment fix it? The jury is still out. I'll give it a few more days before declaring victory.

Ummm... dumb question. Have you tried with a different, purely analog scope...? Spikes like that are prime candidates for digital artifacting. If it's a repeating signal, no reason not to double check yourself with analog.

mnem
 

[tautech]

Med, are you really poking the HV innards of that scope with a 1x probe ?
The additional capacitive loading in 1x certainly could be effecting the stability of the circuitry and giving you false info.

Nope, 10X probe. I did not change the settings on the scope.

Ah OK all good then. 

So showing 1x input attenuation was just a test to see if we were being observant enough ? 

Wasn't my intention just didn't bother. If the sweep went intermittent it bounces all around so if that occurred (it didn't today) I was simply looking for a waveform that was unstable. That would have been the smoking gun. Besides...it's near impossible to put anything past you guys. 

In meantime I have disconnected the Siglent and done several power ups. That is when the fail is most likely to occur. So far, rock steady. Did that trimmer adjustment fix it? The jury is still out. I'll give it a few more days before declaring victory.

Ummm... dumb question. Have you tried with a different, purely analog scope...? Spikes like that are prime candidates for digital artifacting. If it's a repeating signal, no reason not to double check yourself with analog.

mnem
 

Yeah but overshoots are less likely using a probe vs a BNC connection.
I'm be more worried about the signal amplitude not saturating part of the circuit and the presence of the negative going spike doing crazy things. Looking at the waveform examples it just shouldn't be there. 

[med6753]

Med, are you really poking the HV innards of that scope with a 1x probe ?
The additional capacitive loading in 1x certainly could be effecting the stability of the circuitry and giving you false info.

Nope, 10X probe. I did not change the settings on the scope.

Ah OK all good then. 

So showing 1x input attenuation was just a test to see if we were being observant enough ? 

Wasn't my intention just didn't bother. If the sweep went intermittent it bounces all around so if that occurred (it didn't today) I was simply looking for a waveform that was unstable. That would have been the smoking gun. Besides...it's near impossible to put anything past you guys. 

In meantime I have disconnected the Siglent and done several power ups. That is when the fail is most likely to occur. So far, rock steady. Did that trimmer adjustment fix it? The jury is still out. I'll give it a few more days before declaring victory.

Ummm... dumb question. Have you tried with a different, purely analog scope...? Spikes like that are prime candidates for digital artifacting. If it's a repeating signal, no reason not to double check yourself with analog.

mnem
 

Yeah but overshoots are less likely using a probe vs a BNC connection.
I'm be more worried about the signal amplitude not saturating part of the circuit and the presence of the negative going spike doing crazy things. Looking at the waveform examples it just shouldn't be there. 

The Siglent was telling the truth.

[mnementh]

Well, now you know.  I wasn't trying to cast aspersions on Tautech's progeny; I just thought it would be wise to make sure.

mnem
 

[cyclin_al]

Aww jeez... I picked the bones of last night's roast chicken for my lunch, and went to the loo afterwards. Come back and find that my son, trying to be helpful, had already taken the carcass and container from my desk and processed them into garbage and compost.

Unfortunately, I hadn't weighed the carcass, so have no idea how much I actually ate. Aside from that it was less than 380 grams, the before weight.

mnem
And I can't even get mad, because he was being helpful...

Opportunity to talk about becoming more green, with the 3Rs, for next time:

Reduce
- I am sure you would have done a fine job of reducing the leftovers if you had the chance to finish
ReUse
- Use that carcass with some rice (barley if you have a turkey carcass) to make a soup; it makes the loads of veggies into some of the best tasting veggies ever!
Recycle
- I recommend recycling it before certain other kinfolk go as far as using the leftovers to make headcheese ...  YMMV

Great idea, but sadly, I'm the only zoop-eater in the whole house.  I can't have it, so straight to the compost. 

mnem
         
*~mnem's infamous split-pea zoop~*

Whew, I am glad the rest of you are keeping track.  Not being in the same situation, makes those details hard to remember.  Of course, I shoulda known 

In that case:

[mansaxel]

Other TE problem here. A couple years ago, I bought a W & G optical test set used from the UK (back when the UK was a country you happily bought things from instead of laughing at its narrow-majority-inflicted problems), around 100£ for source and meter. I've been worried about its accuracy for some time, because I've gotten strange readings from measuring through lines using the source into the meter, as one does.  The symptoms were seriously low power levels recorded.

Yesterday evening I had my plan formulated, and went at it. I plugged a 10G LR transceiver with DDM (Digital Diagnostic Monitoring) into the free SFP slot on my living room switch, and took a look at the values:

Code: [Select]

STROMSCHRANK#sh interfaces te 1/0/1 transceiver detail
...
           Optical            High Alarm  High Warn  Low Warn   Low Alarm
           Transmit Power     Threshold   Threshold  Threshold  Threshold
Port       (dBm)              (dBm)       (dBm)      (dBm)      (dBm)
---------  -----------------  ----------  ---------  ---------  ---------
Te1/0/1     -1.5                 0.0        -1.0        -6.0       -7.0

           Optical            High Alarm  High Warn  Low Warn   Low Alarm
           Receive Power      Threshold   Threshold  Threshold  Threshold
Port       (dBm)              (dBm)       (dBm)      (dBm)      (dBm)
-------    -----------------  ----------  ---------  ---------  ---------
Te1/0/1    -40.0                 0.0        -1.0       -16.0      -17.0

The important part we're seeing here is that it claims to push -1,5dBm out. I connected the meter up, after having done the entire IEC-mandated inspection and cleaning procedure, and got a reading of -1,62 dBm. That is entirely acceptable; losing 0,12dB over two splices is nothing to  cry about, au contraire! It is quite reasonable.

OK, so we know it's gotta be the the source. Source then got inspected and cleaned according to the manual, which means lifting the bulkhead FC connector from the enclosure, disconnecting the internal cable connector, and inspecting and cleaning the ferrule. Am not entirely happy with the end face on the 1310nm output, there are contaminations that I can't clean off. The 1550nm output has a pristine ferrule anyway, so that's not the major problem, because I'm losing 27dB compared to what the source's supposed to put out. On both wavelengths.

I need to get hold of documents, and dare opening the unit. Cal is 4 years overdue anyway.

[tautech]

Well, now you know.  I wasn't trying to cast aspersions on Tautech's progeny; I just thought it would be wise to make sure.

mnem
 

TBH I have little time for the bottom of the barrel Siglents however they do work as expected although their feature set is minimal yet for Med's basic poking around as a sanity check they are fine.
Never marketed the DL's here but started with the CNL's and CML's which today can now only be described as very basic too whereas the little SDS1202X-E like Bd's will eat these things for breakfast !
Ya get what ya pay for ! 

[mnementh]

Oh dear. The weakness of my will is only to apparent.

I couldn't resist this diddy scope for £36+shipping - my second (and probably last) thing made by Sinclair/Thurlby.

Let's hope the trace still works when it arrives.   

To me, that thing smells like a junction tester looking for a place to happen. 

mnem
 

Non Linear Systems mini scope here. (No, not interested)   eBay auction: #174964350030

Ugggh. Did you see the heinous Vert and Time selector abortions on that thing? Only thing it really is good for is to run in X/Y mode.

But not a pig in a poke for US$170 to me in the GWN. 

Hell, I'd probably think twice aboot it for $20 at a hamfest.

mnem
 

[mnementh]

Did anybody else notice the PCBWay advert at the bottom of the page where they're offering new soldermask colors, including titty pink...?

I can think of so many, so very wrong ways to misuse that... 

mnem
two words: neopixel pasties.

[Cerebus]

Don't be silly, you can't put neopixels on a pastie, they'd be too crunchy.



Edit: Bugger! I'm hungry now.

[Zucca]

wondering how many of you here are subbed to 3Blue1Brown...



He is amazing in my eyes... and yes I love math...

[med6753]

I took one semester of calculus in 1972, worked my tail off and managed to get a B in the course, and then promptly forgot everything I learned and never looked back. 

[Zucca]

Did you remember if you like the professor teaching it?

IMHO 80% is not your personal taste but how they teach....

I truly believe either you are born with the teaching skill or not... no matter how much you know...

[med6753]

Did you remember if you like the professor teaching it?

IMHO 80% is not your personal taste but how they teach....

I truly believe either you are born with the teaching skill or not... no matter how much you know...

I don't remember his name but he was a no nonsense prof with no sense of humor and overall not very likeable. The one thing that got me through that course is a bunch of us students formed a study group and we met daily to discuss what we had been taught and review the homework. If it weren't for that group I certainly would have failed. Math is NOT one of my strong points. 

[0culus]

In my school career, I had some truly terrible professors (the ones that just don't care are worse than the ones that are hard to get on with) and some truly awesome ones. One of the best was one of the math professors who mainly taught really advanced stuff...he is the finest lecturer I've ever had the pleasure of sitting in on, and he was most gregarious with office hours.

[med6753]

And then we had this nutty physics professor. Professor Olanoff. A wacky Russian. Really likeable but absent minded. Like the time he drove to a park to let his dog run and then got in his car and drove home and forgot the dog.  And he would tell us these things. But his lectures were boring and he used to fill the blackboard from top and bottom with notes. One time he's bent over filling the bottom of the blackboard and we took a laser and shined it on his arse. 

And there was the time one of our crew caught him coming out of a porno theater.        One guy had the balls to ask him in class how was the movie? 

[Zucca]

Yes... there are crazy beasts in front of students at universities.

IMHO it is the academic process that drive you nuts... at least in Italy you have to be the professor slave for years in a dirty lab making no money before hoping to becoming one... it is frustrating and it damages healthy people brain sanity.

Back to math: in my first math exam course the professor was explaining the real numbers set R. He explained the concept of accumulation points.... He turned around and told us:"Remember in R, terrible things are happening".
He had steel balls, I loved him, then hated him, then loved him again.

I'm telling you I could start over the university again tomorrow, it was such a pleasure to learn all that shit.

[cyclin_al]

wondering how many of you here are subbed to 3Blue1Brown...



He is amazing in my eyes... and yes I love math...

I use math as a tool.  It helped me understand kinda sorta what he was talking about.
That was beyond a tool, but fine art, in an extremely complementary manner 

[cyclin_al]

I took one semester of calculus in 1972, worked my tail off and managed to get a B in the course, and then promptly forgot everything I learned and never looked back. 

Calculus 2 was extremely tough.

Differential equations the next year went much better... Yes, it did have something to do with the teacher, more to do with the students.
Differential equations class was in an underground engineering lecture hall.  The room was so large, that the blackboards to the sides of the lectern were angled to provide a better view.  I think there were 4 or 5 blackboards across the front of the room.  One class, a couple of classmates hid behind those side blackboards.  Others in the front row had signals by coughing, sneezing, etc.  On the appropriate signal (when the teacher was looking at another blackboard), someone would lean over the top of the blackboard and modify the line of the equation in some manner.  Once hidden again, someone in the class would ask a question, having the teacher go back to that line of the equation.
The teacher eventually got a bit exasperated and frustrated, since it went on for several occasions over a period of at least 10 minutes.  Eventually, the teacher spotted them in the act of modifying the equation. 
Everything went silent, and the teacher then said "Last time that happened, students came out of the floor".
We never figured out if that was a successful prank on the teacher, or if the teacher pranked the class by playing along... but certainly everyone paid attention in every class!

[beanflying]

Did you remember if you like the professor teaching it?

IMHO 80% is not your personal taste but how they teach....

I truly believe either you are born with the teaching skill or not... no matter how much you know...

I remember the Calculus lecturer of all my Maths stream courses. Dr Alistair Carr - top 'teacher' in spite of one of the more dry subjects.

My Probability and Sadistics Lecturer his name was  All I remember was the boring monotonal drone in two hour blocks of my life I will never get back 

[Brumby]

I took one semester of calculus in 1972, worked my tail off .....

That reminds me of my first encounter with calculus in my senior year of high school.  Boy, did I go to town!  I could wrangle all sorts of integrals and differentiation was a doddle.  Sat down to the final exam and there was ONE question on the subject that I could have answered after a few lessons.  I felt cheated!

Then I hit the wall with some charming exercises on matrices - something I had barely touched on.  Fortunately, there was question requiring a 3D geometry proof that I had never encountered before - but it all just fell together for me.  I got a good pass in the subject, but I'm still dirty about the calculus.

... and then promptly forgot everything I learned and never looked back. 

Same.