Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 18859677 times)

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Offline Neomys Sapiens

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119675 on: May 13, 2022, 11:22:46 pm »

- S-1828 made by " SI " in 1974. Or so I understand.

Then a couple made by RCA :

- CVT.......... 418
- CXK ....... 3M


I think you got the RCA types wrong, because the '64595' appears in the same place and has the same number of places as, for example '40319' etc., which are IDENTIFIABLE RCA part numbers. That said, I have two '64115' devices from RCA (also TO-3), on which I came up empty not only from the internet, but every databook which I have in print or PDF. Nada, zero, nil, rien, gornischt. Oh yeah, one of those totally unspecific 'parts search' sites associates the number with RCA, but that could just mean than someone has tried before me.

No RCA or Harris discrete / power databook and no other semiconductor data or substitution tables list ANY 64xxx number which could beeven remotely connected to the components in question, be it mine or yours.

One information is available from unknown sources: I have a '63857' (RCA) in TO-66 size, which I have marked down as a thyristor(SCR) without further data. Hm. When I get near the big TO-3 box, I will subject all of the unclear ones to a test with the Atlas DCA-75pro. Let's see what the wondersome device says. Other conceivable types, which are frequently packaged in TO-3 are triacs, double diodes, IGBTs, and MOSFETs.

But we must keep in mind that we can't even rule out categories on which it is completely lost, as it could be a thermoswitch, or any other special thing.
Maybe it is a RCA test item, and all devices intended for dimensional/mechanical inspection are '64115' and those for hermeticity test are '64595'. In such a case, we will never find anything and there could be literally anything inside, including random devices or nothing.  :wtf:

And I have something on the SDT9308, although not much..

And you seem to have gotten ahead of me again - I had the SFC2309 erroneously listed as a 9V regulator.
Well done, grenouille électronique!
 
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119676 on: May 14, 2022, 12:50:28 am »
I hate to break it to you, but the first thing your ears do is a Fourier analysis in the cochlear, then your nerves translate that into a set of digital PCM signals and finally your brain tries to reconstruct the signal using a neural network to comprehend it. So any arguments that the whole natural signal chain is analogue fall apart.
Quite.

Add in that the whole ear-brain system is horribly non-linear in every dimension you can think of. If it wasn't, audio compression wouldn't work!

Perhaps so. But has anyone determined our hearing's sample rate?

You'll have to define what you mean by that.

For example, if you consider the long (by electronic standards) response time of the nervous system, you could conclude that (say) 100 samples per second would be sufficient to cover it.
Mmmmhmmm... but we're talking about ~15,000 cilia in the human ear, all processed in parallel. x2. And I for one have no idea what the bit depth per single cili (?) would be; certainly much more than binary.

You appear to be doing the equivalent of confusing baud rate with bit rate, or clock rate with instructions per second.

Quote
Bet it's infinitely better than any digital format. After all, billions of years of evolution.
In the same way that the human eye is better than a camera? NOT!

It is obvious that the human eye is superior to a camera at what it is intended to detect;

The human eye/brain is crap, both absolutely and relative to other independently-evolved eye variants.  Start by considering why our eyes have a blind spot. Other eyes have avoided that grossly bad engineering. Then go on to consider the remarkably small field of decent vision, i.e. the fovea centralis.

We can't perceive just how crap, since we are limited to what we can percieve. Well, that's not quite true, as shown by optical illusions. Have a look at the 148(!) examples at  https://michaelbach.de/ot/index.html Many are familiar, but some are astounding; this one is gobsmacking https://michaelbach.de/ot/mot-mib/index.html


Quote
otherwise we wouldn't have all these publicized problems with Apple's child-safe bunk identifying a digitized pic of a dog as probable child-porn. It's both the sensor and the processing that makes a working eye vs a working camera.

That, and Teslas, poor performance don't make the human eye/brain good.

Quote
The difference with a camera is how much more range it can detect and of course the fact of once again, parallel bus for the eye vs serial for a camera.

Too simplistic, but at least you are acknowledging that cameras are better in many ways.

Quote
For a real appraisal, you cannot separate the human eye from the visual cortex... it is a system all directly tied into the brain itself. The problems we have quantifying how it all works are similar to that of trying to gauge sound with a tape measure; the tools we have at our disposal are... ahem... less than ideal.

Indeed you can't separate them; the brain does a surprisingly good job of guessing/inventing what the eye omits.

Analogies are dangerous, and often confuse the issues.
I am not confusing baud rate with bit rate, or clock rate with instructions per second. None of the above. I'm considering 2 x ~15000 cilia in parallel, regardless of bitrate, and Ifni knows how many bits the DAC associated with each cilia is deep. Nothing more.

You say the human visual apparatus is crap; yet tests have shown that the human eye can consistently tell a human form from a dog and correctly identify both from such a distance as to represent approximately 12 pixels of information. That is astounding to me, and that is the "product of billions of years of evolution" that med was talking about.

And the way our eyes/visual cortex work is both partly caused by and partly the cause of how we grasp abstract concepts. If we hadn't evolved our eyes the way we have for tool-using and manual dexterity, we literally would not think the way we do.

Trying to separate the optical sensor from what it is optimized for is folly.

mnem
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« Last Edit: May 14, 2022, 01:00:39 am by mnementh »
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Offline mansaxel

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119677 on: May 14, 2022, 04:20:21 am »
that fritz repeater is a piece of shit not even worth the 50 grams. I'll try to return it.
Using the second fritz box as a repeater works like a charm.

I've used in several installations AVM repeaters, including the 3000.
No problems at all, they just simply work. Installation can be a little tricky
but once they are appearing in the mesh, everything is fine.
it trashed my config a couple of times, grabbed mesh master role and completely fucked up my previously working mesh config plus Internet connectivity forcing me into crawlspaces to physically rewire and reset stuff.
I fucking hate it. my life is too short to fart around with this  Hope Reichelt takes it back.

The pros who build wireless have ceased to be amazed by the amount of wire required by wire"less".

Hence, repeater nets, meshes, et al., are at best hacks. There is no substitute for actual wired access points in any of this.  Just accept that and build out. (when time comes)

Offline Saskia

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119678 on: May 14, 2022, 04:50:02 am »
yes, absolutely. the fritz box is wired as a DHCP client to the other Fritzbox and gets the WLAN data via lan. The repeater did not like a cable connection, last it's lan bridge data and assumed mesh master.
it seems that I can work with that master sla cc e config for now.
 

Offline mansaxel

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119679 on: May 14, 2022, 04:54:06 am »
No discord for me tonight. Out with the wife.

Offline Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119680 on: May 14, 2022, 07:18:59 am »

- S-1828 made by " SI " in 1974. Or so I understand.

Then a couple made by RCA :

- CVT.......... 418
- CXK ....... 3M


I think you got the RCA types wrong, because the '64595' appears in the same place and has the same number of places as, for example '40319' etc., which are IDENTIFIABLE RCA part numbers. That said, I have two '64115' devices from RCA (also TO-3), on which I came up empty not only from the internet, but every databook which I have in print or PDF. Nada, zero, nil, rien, gornischt. Oh yeah, one of those totally unspecific 'parts search' sites associates the number with RCA, but that could just mean than someone has tried before me.

No RCA or Harris discrete / power databook and no other semiconductor data or substitution tables list ANY 64xxx number which could beeven remotely connected to the components in question, be it mine or yours.

Hmm, in agreement with Factory then !  OK looks hopeless... I think I will put all the un-indentifiable parts I stumble upon, in a box.. then decide later what to do with them...  I guess I could use them when I am angry or bored... I could just pick a part in that box and saw it open to see the die, and play with it on the bench with high current and voltages until the magic smoke escapes. Seeing the die literally melt, before my eyes...

Quote from: Neomys Sapiens
And you seem to have gotten ahead of me again - I had the SFC2309 erroneously listed as a 9V regulator.

Looked at your catalogue... they got something else wrong it appears ! They list the 2N3771 as 15 amps, but the actual sdatasheet for it, which I have, says it's 30A ! Not quite the same...
So looks like old catalogues are useful but should not be trusted 100% either !
 

Offline Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119681 on: May 14, 2022, 07:42:24 am »
It's usually the AF11x series (AF117 for example) from Mullard that often suffer from tin whiskers. Some EU made ones supposedly have epoxy type fill, instead of silicone jelly and the whiskers don't grow through epoxy. Of course Ge trannystors can fail in other ways.

Recommended reading if you haven't seen it, NASA report on tin whiskers in AF11x/OC17x type Ge transistors.
https://nepp.nasa.gov/whisker/anecdote/af114-transistor/2005-Brusse-tin-whiskers-AF114-transistors.pdf

Thanks, it's interesting as if offers a modern look on specific vintage parts, and has cool photographs. The other day I came across another report, also American but from a different agency can't remember which one (I failed to download it, stupid me...), maybe the FDA, but it was much older, from 1986 IIRC, so no pîctures but lots of interesting text on background, what might because the whiskers and how to prevent them.

I remember bits of it though. It said that tin whiskers were ALREADY a known problem in the freaking '30s !!!  :scared:   So hardly a new thing.
Also said that many manufacturers often confused tin whiskers with another type of whiskers that was already known, and that's much less mysterious, which grows based on the sole presence of voltage / electric filed, and humidity. Even many equipment manufacturers pretended, in good faith but misinformed, that their product was "tin whisker" proof, when it was not (and that caused a famous pace maker scandal / failure over there apparently ! ), simply because the manufacturer made his product sealed, moisture tight, hence this other type of whiskers could not grow.... but this had no relevance whatsoever to the risk of growing "our" tin whiskers.

They said that tin whiskers had been studied under lots of angles, lots of experiments have been made to try and characterize them, see what factors influenced their growth, how and how much... so they did have some knowledge of them but... they also said that on a physics, fundamental level, they didn't really understand how they could develop/form to begin with.

 

Offline Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119682 on: May 14, 2022, 08:01:03 am »


OK so I am done with the TO3 packages now.

23 of them in total. 3 that I could not identify, if people can help, you are most welcome. If not... straight to the junk bin, since an unidentified anything is as useful as a rock. Maybe I could saw them open out of curiosity...

Anyway as you can see they are :

- S-1828 made by " SI " in 1974. Or so I understand.

...snip...



Well the S-1828 gives nothing, but 1110715 cross references to NFR8117 diode on the parttarget NSN stock list website and searching for NFR8117 finds a Digital parts list here http://vtda.org/docs/computing/DEC/Handbooks/EB-21850-75_SparesKitHandbook_1982.pdf
The DEC book lists it as PIV 75, 20A in T03 package, under part# 11-10715-00 (also cross-references back to the NSN list). Does it test as a diode?


David

Thanks a lot !  :-+

Yes it does indeed register as a double diode when I shove it into the chinese tester : common cathode on the metal can. The two anodes on the two pins.
However what worries me is that the tester also displays a 5 ohm resistance between the two anodes ?!  :o
That's weird... maybe it's toast...

« Last Edit: May 14, 2022, 08:04:35 am by Vince »
 

Offline Specmaster

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119683 on: May 14, 2022, 08:11:43 am »
On the (Woodworking) Bench Tonight:



So a few days ago, I bought these two belt sanders (see here in the What'd Ya Buy? thread), figuring I'd do a Amazon vs Horror Fraught cheapies shootout; see which was the best.  ;)

Turns out... they're both the same exact fucking sander under the plastic shell. Aside from the part that's red on the Bauer, everything... motor, electronics, belt drive to gearbox, even the drive & shoe casting, etc... all exactly the effing same Chinesium bits.

The only real difference then is the features, aside from the fact the dust collector on the Bauer is 50% blocked due to a design flaw, and doesn't work work a fuck. The Galax Pro has adjustable front handle, a dust collector that works, and that little flip-up cast cover so you can actually do some inside curves with the thing.  :-+ :-+ :-+

So... I just took the red one back to Horror Fraught and used the refund to get a jitterbug and sanding discs.  :-DD

I've made a lot more progress than you can see here... I've finished the stripping and now working on smoothing it out again. I'm going out to work on it some more, now that the kiddles are fed. ;D

mnem
*toddles off to get his grit on*
I've come across this a few times with the so-called cheap shops like Aldi and Lidl and some of their tools. I mean they clearly are not the same as say Bosch but there are also many other brands out there that are lesser known because they don't have the massive marketing budgets. These are the ones that represent in the main reasonable quality and will if treated right last many years, and, it these makes who will badge, or body engineer their products  to become another house product for another company. We have electrical wholesalers who clearly are not manufacturers, but they do have their own range of products ranging from electrical wiring accessories right the way through to power tools etc. I used to work for one manufacturer who was asked many times if they would supply wholesalers with slightly modified products and label them differently for them, they always turned down the request however.
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Offline Robert763

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119684 on: May 14, 2022, 08:31:24 am »
[<SNIP>

Looked at your catalogue... they got something else wrong it appears ! They list the 2N3771 as 15 amps, but the actual sdatasheet for it, which I have, says it's 30A ! Not quite the same...
So looks like old catalogues are useful but should not be trusted 100% either !

Not just old ones. I recently had to tell ON Semi that the current (2020) datasheet for a MOSFET had the incorrect pinout  :palm:
 
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119685 on: May 14, 2022, 08:59:53 am »
Decided to take a jaunt out to Dunstable boot sale next Sunday and make my house move more difficult  :-DD.

Anyone else turning up?
 
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Offline Robert763

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119686 on: May 14, 2022, 09:15:09 am »
Decided to take a jaunt out to Dunstable boot sale next Sunday and make my house move more difficult  :-DD.

Anyone else turning up?

I'll be there as a buyer. Do you want me to bring the Tek 7000 scopes?  >:D 
(PM me if you do)
 
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Offline bd139

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119687 on: May 14, 2022, 09:29:19 am »
Decided to take a jaunt out to Dunstable boot sale next Sunday and make my house move more difficult  :-DD.

Anyone else turning up?

I'll be there as a buyer. Do you want me to bring the Tek 7000 scopes?  >:D 
(PM me if you do)

Tempting but will have to pass for now as I’m not sure I’m going to have anywhere to put them yet. The current situation looks like digital scope level space only  :-\. Mostly going for quick bounce opportunities and smaller parts and to shed some boredom.
 
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Offline Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119688 on: May 14, 2022, 09:50:38 am »
Just finished the recap of the Tek 180A Time Mark Generator now that I have received the yellow axial caps. Well I am still missing one last cap, the biggest one in the top right corner in the pic. 1uF. For now I am using a salvaged radial cap, does the job but if just for looks and consistency, I am going to put a yellow axial there as well. BU said he had that particular cap so I am waiting for him to excavate them from wherever they might be hiding from him. At least they are yellow so they are easy to see, should help him find them   >:D

So I put all these caps in. Then I fired up the scope so I can check again all the stages to adjust them for the new caps.

The beast still works perfectly so that's a relief right there... might be old but not yet falling apart.  :phew:

Look at that beauuutiful comb it can produce, no less than 3 different markers at the same time : 100us + 50us + 10us .... just because I (it) can ! 8)

Still needs a bit of cleaning of the front panel and inside. Bit dusty in there. Not that much but enough that I would want to give it a little clean.



« Last Edit: May 14, 2022, 10:00:54 am by Vince »
 
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Offline AVGresponding

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119689 on: May 14, 2022, 10:05:22 am »
Decided to take a jaunt out to Dunstable boot sale next Sunday and make my house move more difficult  :-DD.

Anyone else turning up?

Too far for me to go unfortunately.
nuqDaq yuch Dapol?
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Offline AVGresponding

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119690 on: May 14, 2022, 10:24:05 am »
Hmmmm... mnem..?

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Offline tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119691 on: May 14, 2022, 11:03:37 am »
Decided to take a jaunt out to Dunstable boot sale next Sunday and make my house move more difficult  :-DD.

Anyone else turning up?

I'll turn up, not sure whether or not I'll be selling.

Afternoon will be spent delivering heirlooms to relatives, not making the annual pilgrimage to TNMoC.
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119692 on: May 14, 2022, 11:13:38 am »
I hate to break it to you, but the first thing your ears do is a Fourier analysis in the cochlear, then your nerves translate that into a set of digital PCM signals and finally your brain tries to reconstruct the signal using a neural network to comprehend it. So any arguments that the whole natural signal chain is analogue fall apart.
Quite.

Add in that the whole ear-brain system is horribly non-linear in every dimension you can think of. If it wasn't, audio compression wouldn't work!

Perhaps so. But has anyone determined our hearing's sample rate?

You'll have to define what you mean by that.

For example, if you consider the long (by electronic standards) response time of the nervous system, you could conclude that (say) 100 samples per second would be sufficient to cover it.
Mmmmhmmm... but we're talking about ~15,000 cilia in the human ear, all processed in parallel. x2. And I for one have no idea what the bit depth per single cili (?) would be; certainly much more than binary.

You appear to be doing the equivalent of confusing baud rate with bit rate, or clock rate with instructions per second.

Quote
Bet it's infinitely better than any digital format. After all, billions of years of evolution.
In the same way that the human eye is better than a camera? NOT!

It is obvious that the human eye is superior to a camera at what it is intended to detect;

The human eye/brain is crap, both absolutely and relative to other independently-evolved eye variants.  Start by considering why our eyes have a blind spot. Other eyes have avoided that grossly bad engineering. Then go on to consider the remarkably small field of decent vision, i.e. the fovea centralis.

We can't perceive just how crap, since we are limited to what we can percieve. Well, that's not quite true, as shown by optical illusions. Have a look at the 148(!) examples at  https://michaelbach.de/ot/index.html Many are familiar, but some are astounding; this one is gobsmacking https://michaelbach.de/ot/mot-mib/index.html


Quote
otherwise we wouldn't have all these publicized problems with Apple's child-safe bunk identifying a digitized pic of a dog as probable child-porn. It's both the sensor and the processing that makes a working eye vs a working camera.

That, and Teslas, poor performance don't make the human eye/brain good.

Quote
The difference with a camera is how much more range it can detect and of course the fact of once again, parallel bus for the eye vs serial for a camera.

Too simplistic, but at least you are acknowledging that cameras are better in many ways.

Quote
For a real appraisal, you cannot separate the human eye from the visual cortex... it is a system all directly tied into the brain itself. The problems we have quantifying how it all works are similar to that of trying to gauge sound with a tape measure; the tools we have at our disposal are... ahem... less than ideal.

Indeed you can't separate them; the brain does a surprisingly good job of guessing/inventing what the eye omits.

Analogies are dangerous, and often confuse the issues.
I am not confusing baud rate with bit rate, or clock rate with instructions per second. None of the above. I'm considering 2 x ~15000 cilia in parallel, regardless of bitrate, and Ifni knows how many bits the DAC associated with each cilia is deep. Nothing more.

You say the human visual apparatus is crap; yet tests have shown that the human eye can consistently tell a human form from a dog and correctly identify both from such a distance as to represent approximately 12 pixels of information. That is astounding to me, and that is the "product of billions of years of evolution" that med was talking about.

And the way our eyes/visual cortex work is both partly caused by and partly the cause of how we grasp abstract concepts. If we hadn't evolved our eyes the way we have for tool-using and manual dexterity, we literally would not think the way we do.

Trying to separate the optical sensor from what it is optimized for is folly.

mnem
 :blah:

When someone discusses "sampling rate" in a highly parallel!system, then flips to "15000 cilia", then they are flipping between bits/baud or clock rate/IPS.

Sure, the human eye/brain distinguishes some things fairly well, but it makes many many mistakes too. The optical illusions are a good repeatable "in a nutshell" demonstration of that. Look at the second example I gave; big things randomly appear and disappear.

As for "grasping abstract concepts", the perceptron concept of a grandfather neuron was debunked decades ago.
« Last Edit: May 14, 2022, 11:16:13 am by tggzzz »
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline AVGresponding

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119693 on: May 14, 2022, 11:18:19 am »
Most optical illusions are synthetic; the human vision system is evolved to deal with the real natural world.
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Offline Cerebus

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119694 on: May 14, 2022, 12:59:02 pm »
As for "grasping abstract concepts", the perceptron concept of a grandfather neuron was debunked decades ago.

To be fair to people who developed the hypothesis I don't think you can say "debunked" about the perceptron hypothesis, rather say "was abandoned when the hypothesis was found to not be supported by experimental data". It's not like the originators kept trying to sell the idea years after it was past it's sell-by date; unlike people at the other end of psychology who persisted in trying to flog rubbish about dreaming about envying the size of your Mother's penis as explanation for certain mental processes for a century longer than they should have.

Furthermore there's clearly no "abstract concept" involved in some of the things the visual system does well. At no point in a ball being thrown at one unexpectedly are any abstract constructs involved, one either catches or ducks well before any abstract notion of what object has been thrown at one develops.

Most optical illusions are synthetic; the human vision system is evolved to deal with the real natural world.

Most modern, as opposed to historical, optical illusions were specifically developed to try and probe the visual perceptual system to find out how it works. Some yielded useful data about how some aspects of the visual system work, others just exposed cracks in it by finding things that it does badly.
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Offline tggzzz

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119695 on: May 14, 2022, 01:31:50 pm »
That is a good response to both my post and AVG's
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline BU508A

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119696 on: May 14, 2022, 01:37:16 pm »
Just finished the recap of the Tek 180A Time Mark Generator now that I have received the yellow axial caps. Well I am still missing one last cap, the biggest one in the top right corner in the pic. 1uF. For now I am using a salvaged radial cap, does the job but if just for looks and consistency, I am going to put a yellow axial there as well. BU said he had that particular cap so I am waiting for him to excavate them from wherever they might be hiding from him. At least they are yellow so they are easy to see, should help him find them   >:D

So I put all these caps in. Then I fired up the scope so I can check again all the stages to adjust them for the new caps.

The beast still works perfectly so that's a relief right there... might be old but not yet falling apart.  :phew:

Look at that beauuutiful comb it can produce, no less than 3 different markers at the same time : 100us + 50us + 10us .... just because I (it) can ! 8)

Still needs a bit of cleaning of the front panel and inside. Bit dusty in there. Not that much but enough that I would want to give it a little clean.

They are coming from Yorkshire and should arrive any day. I'll let you know as soon as they arrive here.

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

Offline Vince

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119697 on: May 14, 2022, 01:46:25 pm »
Oh ! Sorry BU I didn't mean to be pushy at all, I thought you ALREADY had them in stock, that you bought them XX time / weeks/ months ago, I misunderstood it seems, my bad !  :palm:

 
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Offline mnementh

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119698 on: May 14, 2022, 02:08:19 pm »
I hate to break it to you, but the first thing your ears do is a Fourier analysis in the cochlear, then your nerves translate that into a set of digital PCM signals and finally your brain tries to reconstruct the signal using a neural network to comprehend it. So any arguments that the whole natural signal chain is analogue fall apart.
Quite.

Add in that the whole ear-brain system is horribly non-linear in every dimension you can think of. If it wasn't, audio compression wouldn't work!

Perhaps so. But has anyone determined our hearing's sample rate?

You'll have to define what you mean by that.

For example, if you consider the long (by electronic standards) response time of the nervous system, you could conclude that (say) 100 samples per second would be sufficient to cover it.
Mmmmhmmm... but we're talking about ~15,000 cilia in the human ear, all processed in parallel. x2. And I for one have no idea what the bit depth per single cili (?) would be; certainly much more than binary.

You appear to be doing the equivalent of confusing baud rate with bit rate, or clock rate with instructions per second.

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Bet it's infinitely better than any digital format. After all, billions of years of evolution.
In the same way that the human eye is better than a camera? NOT!

It is obvious that the human eye is superior to a camera at what it is intended to detect;

The human eye/brain is crap, both absolutely and relative to other independently-evolved eye variants.  Start by considering why our eyes have a blind spot. Other eyes have avoided that grossly bad engineering. Then go on to consider the remarkably small field of decent vision, i.e. the fovea centralis.

We can't perceive just how crap, since we are limited to what we can percieve. Well, that's not quite true, as shown by optical illusions. Have a look at the 148(!) examples at  https://michaelbach.de/ot/index.html Many are familiar, but some are astounding; this one is gobsmacking https://michaelbach.de/ot/mot-mib/index.html


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otherwise we wouldn't have all these publicized problems with Apple's child-safe bunk identifying a digitized pic of a dog as probable child-porn. It's both the sensor and the processing that makes a working eye vs a working camera.

That, and Teslas, poor performance don't make the human eye/brain good.

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The difference with a camera is how much more range it can detect and of course the fact of once again, parallel bus for the eye vs serial for a camera.

Too simplistic, but at least you are acknowledging that cameras are better in many ways.

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For a real appraisal, you cannot separate the human eye from the visual cortex... it is a system all directly tied into the brain itself. The problems we have quantifying how it all works are similar to that of trying to gauge sound with a tape measure; the tools we have at our disposal are... ahem... less than ideal.

Indeed you can't separate them; the brain does a surprisingly good job of guessing/inventing what the eye omits.

Analogies are dangerous, and often confuse the issues.
I am not confusing baud rate with bit rate, or clock rate with instructions per second. None of the above. I'm considering 2 x ~15000 cilia in parallel, regardless of bitrate, and Ifni knows how many bits the DAC associated with each cilia is deep. Nothing more.

You say the human visual apparatus is crap; yet tests have shown that the human eye can consistently tell a human form from a dog and correctly identify both from such a distance as to represent approximately 12 pixels of information. That is astounding to me, and that is the "product of billions of years of evolution" that med was talking about.

And the way our eyes/visual cortex work is both partly caused by and partly the cause of how we grasp abstract concepts. If we hadn't evolved our eyes the way we have for tool-using and manual dexterity, we literally would not think the way we do.

Trying to separate the optical sensor from what it is optimized for is folly.

mnem
 :blah:

When someone discusses "sampling rate" in a highly parallel!system, then flips to "15000 cilia", then they are flipping between bits/baud or clock rate/IPS.

Sure, the human eye/brain distinguishes some things fairly well, but it makes many many mistakes too. The optical illusions are a good repeatable "in a nutshell" demonstration of that. Look at the second example I gave; big things randomly appear and disappear.

As for "grasping abstract concepts", the perceptron concept of a grandfather neuron was debunked decades ago.

You are the one saying bitrate... I have always been saying it is impossible to gauge just how much information is processed by the visual and auditory senses, because the best we can estimate is very crude analogs between meatware and silicon. We literally do not have the correct tools to make even a reasonably fair comparison.

Developing those tools is actually one of the most exciting fields in modern medicine and technology... the more we learn, the more we find we still need to learn.

As for the perceptron model... that's a label that has been misapplied so many times to so many different aspects of the human brain... yet as the science of psychology refines itself generation over generation, we find more and more proof that how you live changes how you think, and a large part of what we "see" is preprocessed differently in the visual cortex based on how we live.

Just like our native language affects how we see ourselves and our place in the world and in many ways how we put concepts together, how we live affects how we see the world. Both literally and figuratively.

mnem
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Offline Ole

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Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #119699 on: May 14, 2022, 02:11:01 pm »

Ping us again .....on your Sat evening when Discord is about to kick off and one of us can flick you an invite to TEA once we know your Discord handle.
We can do this with EEVblog PM's or here in this thread.

I think it would be best if the new invite link is posted to this thread, so that others couild join as well.
Cheers
Ole
« Last Edit: May 14, 2022, 07:17:16 pm by Ole »
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