Test Equipment Anonymous (TEA) group therapy thread

[pcprogrammer]

True that it happens, but laws are there, only they are not well uphold.

Same as for burning your garden trimmings. Since a couple of years it is prohibited to burn them, but that does not stop the farmers, hell they are just not well informed about it. Even a young farmer who recently graduated from farming school was happily burning a load of sticks and slightly wet hay. The whole house smelled horrible for over a week. We asked him if he knew it was illegal, and his response was "no it is fine, only in the summer it is not allowed". Wrong

As I understood it, it applies to properties less than 4,000 sq metres.

I have a friend who lives in a rural village in France, who's affected by it. He asked the Maire about it, and the Maire told him to be careful and not to create a lot of smoke. He asked his cleaner, she was going to burn her rubbish at night when there was no one around. He asked his neighbours, mainly retired French professional people, they thought it was silly and were going to ignore it. No one takes any notice of it.

He waits until the pile is thoroughly dry so as to limit the smoke, and the weather conditions are right not to cause a nuisance.

Yes, thst id the problem everybody ignores it, but "La personne qui brûle des déchets verts peut avoir à payer une amende de 450 € maximum. Si vous êtes incommodé par les odeurs, vous pouvez par ailleurs engager la responsabilité de votre voisin pour nuisances olfactives." which is in English "The person who burns green waste may have to pay a fine of up to €450. If you are bothered by odors, you can also hold your neighbor liable for odor nuisance."

As of 22-03-2022 it is definitely not allowed. "Non, il est interdit brûler des déchets verts (végétaux secs ou humides) chez soi, que ce soit avec un incinérateur de jardin ou à l'air libre." which is in English "No, it is forbidden to burn green waste (dry or wet plants) at home, whether with a garden incinerator or in the open air."

This is from the government site: https://www.demarches.interieur.gouv.fr/particuliers/peut-on-bruler-dechets-verts-jardin-feuilles-branches

There seem to be some exceptions in case of plants with a disease or when there is no nearby disposal facility. Some towns have a dedicated dumping ground and there are the "déchetteries" which translates as "landfills" but are the places where they have skips to dump stuff like furniture, building waste, plastics, cardboard, etc.

In these cases one has to talk to the mayor and he can give permission. But this is exception not rule.

Can not verify if this is only for civilians and not for farmers.

[m k]

Since everyone is in a bitchy mood today with all this OT stuff let me add my 1st world issue. The spin cycle on our only washer is broke. Spins for about 30 seconds then machine shuts off. Clothes come out soaking wet. Will require two full cycles at $1.50 USD each in the dryer.

Informed the landlord. This shattering event has ruined my entire day. I may have to take up drinking to console myself.

If I recover sufficiently I will have some on topic stuff to post later.

Carry on.

 

Somehow our clothes washer didn't become any better over time.
Now new one is installed and two old ones pushed uphill and luckily up to the ramp and in to the van.
Inflating concrete would be nice, like a Higgs boson extractor, outdoors use only.

[Squarewave]

Going back onto test equipment, if I may.....some time ago, I bought a Conway Precision Masteranger 639. I got it from an auction, can't remember if I bid for it alone or if it was with a bundle. It's happy from DC to 1Ghz, so as I'm trying to justify the space for such items, I'm wondering whether to keep it or not, as I can substitute it for a spectrum analyser and a zero loss probe.

[Cerebus]

Another thing I hate is when the TPTB decide to set a 20mph limit, maybe because there is a school etc, but they never bother to erect the large 20mph sign, often relying on it being painted on the road (FFS), this cannot be seen if covered by another vehicle and when it is uncovered, you could be scanning a side road junction etc and so miss it.

If it's painted on the road and not backed up by honest-to-goodness mandatory speed limit sign at the side of the road it's not a mandatory speed limit, merely advisory. (The Traffic Signs Regulations and General Directions 2016, DfT Traffic Signs Manual Chapter 3). But it's a poor example, why wouldn't you be doing below 20 mph anyway, irrespective of the official limit, knowing that you're near a school?

[mnementh]

I'm certain all you trainspotters know this seminal film, but this is the first I remember seeing it. So either I haven't, or the brain cell that memory was written on died long ago.

mnem

[Vince]

Looks like a giant clutch mechanism / pressure plate...

[gnif]

Guys, please stay on topic here. If you want to discuss something else please create a thread for it.

Edit: More off topic posts will be removed, keep doing it and you will be restricted from participation here.

[tggzzz]

Ok, so it seems the 74AC14 has an output current of 50mA per buffer. So at 4.5V supply, we get a minimum voltage of 4.4V out, which comes to 2ohms source impedance.

To impedance match this to 50ohms, If I parallel 3 buffers (max Vcc/ground current for this chip is 150mA) followed each by a 15ohm resistor, I should get 51ohms impedance, right?

It's 50mA absolute max current! The 4.4V are for a current of 50uA. For a current of 24mA they give 3.86V at 25°C. (Use values closest to use case to calculate the resistance - in this case the 24mA I'd say)
In your example you would have to use 150 ohms (I think you meant to type that) in series to the (unrealistic) 2 ohm to get close to 50 ohm when parallel'd up.

Ah ok. So If my supply is 5.0V, then I could assume I get a volt drop of say 1.14V then?
So with a current of 24mA then I'd have a source impedance of 47.5ohms, which would call for roughly 100ohm resistors?

Well at 4.5V the drop is 0.64V which gives ~27ohms. At 5.5V the drop is 0.64V as well which gives the same 27ohm. Often you see lower output impedances at higher voltages though!
I'll take the average of the 4.5V and 5.5V impedance values to get close to a "at 5V" value. But that's probably gilding the lily and the 4.5V value is more than good enough...
So I'd say take 120ohms in series each, parallel these bad boys up and don't forget to load them with 50R [at the scope (check for maximum power of the internal termination though and use an external one if need be!)]

Here we are with the three buffers followed each by their own 120ohm resistor then all connected to a BNC, then to the scope with a HP passthrough 50ohm terminator.

Not sure that the P-P voltage is enough to be reliably used for TTL stuff?

p-p voltage is irrelevant. What matters is whether the voltages seen by the inputs meet the V_IL and V_IH min/max specification for the receiver. The receiver may or may not be a naked logic gate.

It looks OK for standard old-school 5V TTL, provided that the lower voltage is 0V and the upper voltage is 2.7V. If there is AC coupling anywhere or 1.8V TTL, then no.

[mnementh]

Guys, please stay on topic here. If you want to discuss something else please create a thread for it.

Edit: More off topic posts will be removed, keep doing it and you will be restricted from participation here.

What the hey...?

I didn't even see your post... and what was wrong with mine?

mnem
 

[Cerebus]

Yes I know about the ringing. I just want rough frequency and red/green for this phase.

It vanishes completely if you terminate with something like 1k (the 1k from memory).

[bd139]

I’m not sure if anyone noticed gnif’s post but back ok topic please…

[Cerebus]

Ok, so it seems the 74AC14 has an output current of 50mA per buffer. So at 4.5V supply, we get a minimum voltage of 4.4V out, which comes to 2ohms source impedance.

To impedance match this to 50ohms, If I parallel 3 buffers (max Vcc/ground current for this chip is 150mA) followed each by a 150ohm resistor, I should get 51ohms impedance, right?

See https://www.eevblog.com/forum/testgear/show-us-your-square-wave/msg1902941/#msg1902941

You will need to pay careful attention to PSU decoupling, including lead length inside the package (hint: pins 14+7 is just about the worst choice that could have been made)

One way around that nasty is to parallel several of the tiny surface mount single gate packages. They have much, much better inductive performance thanks to having almost no lead worth mentioning at all. In fact they're so good that you start fussing over the inductance of the resistors rather than the inductance of the IC packaging.

[pcprogrammer]

Guys, please stay on topic here. If you want to discuss something else please create a thread for it.

Edit: More off topic posts will be removed, keep doing it and you will be restricted from participation here.

What is on topic here?

This thread is all over the place with non test equipment related stuff

[BU508A]

Incoming parts today:
80 Intersil ISL95310 ISL95310WIU10Z digital controlled potentiometer (XDCP).
W=10kOhm version.

I've attached the datasheet below.

Planning, to build an LM317 based PSU and do the voltage setting with this.

If somebody is interested in some of them, drop me a PM. Asking 1 Euro per IC plus shipping (isn't that much, those things are tiny. 10-lead MSOP package).

[Squarewave]

Guys, please stay on topic here. If you want to discuss something else please create a thread for it.

Edit: More off topic posts will be removed, keep doing it and you will be restricted from participation here.

What is on topic here?

Test Equipment?

This thread is all over the place with non test equipment related stuff

I think that's his point.

[Zenith]

Guys, please stay on topic here. If you want to discuss something else please create a thread for it.

Edit: More off topic posts will be removed, keep doing it and you will be restricted from participation here.

What the hey...?

I didn't even see your post... and what was wrong with mine?

mnem
 

A shot has been fired across our bows, and we must heave to.

Anyway, this is something for the hopeless TE addict.

It's a Schlumberger/CRC 4760 sweep generator. I got it mainly working about ten years ago and then I got fed up with it. I think it took ages to track down a varicap diode. It did come with the service manual, or I wouldn't have touched it. It's from about 1971 and has Nixie tubes.

I've decided to investigate it and bring it back to life if possible.

[tggzzz]

Ok, so it seems the 74AC14 has an output current of 50mA per buffer. So at 4.5V supply, we get a minimum voltage of 4.4V out, which comes to 2ohms source impedance.

To impedance match this to 50ohms, If I parallel 3 buffers (max Vcc/ground current for this chip is 150mA) followed each by a 150ohm resistor, I should get 51ohms impedance, right?

See https://www.eevblog.com/forum/testgear/show-us-your-square-wave/msg1902941/#msg1902941

You will need to pay careful attention to PSU decoupling, including lead length inside the package (hint: pins 14+7 is just about the worst choice that could have been made)

One way around that nasty is to parallel several of the tiny surface mount single gate packages. They have much, much better inductive performance thanks to having almost no lead worth mentioning at all. In fact they're so good that you start fussing over the inductance of the resistors rather than the inductance of the IC packaging.

For example the 74lvc1g14 gates I used

Alternatives approaches include those used in the 7473 and a few other devices, or some of the more exotic families: put the power pins in the middle.

[mnementh]

I’m not sure if anyone noticed gnif’s post but back on topic please…

Dammit, bd, I've been a good widdle tinkerdwagon!

I've been working hard for weeks here to generate on-topic stuff, and deliberately avoided all the talk of prepping, gun-nuttery and the collapse of civilization... I make one response to the topic folks are on about at the moment, deliberately talking only about one tiny, harmless aspect of it... and I get spanked.



I'm feeling a bit like this right now...   

mnem
*toddles off to do something to get spanked by my wife instead*

[tggzzz]

Strangely inaccurate fleabay title "J J Sullivan Resistance Box Type R603". HW Sullivan would be turning in his grave if his decade resistance boxes could be confused with "JJ Instruments" a.k.a "Jay Jay" a.k.a. "JJ Lloyd Instruments" decade resistance boxes.

https://www.ebay.co.uk/itm/334519973359

And here's one of the pictures:

[Vince]

Are you sure it's a resistance box ? Looks more like a flying saucer to me... not sure, it's kinda blurry ! 

[Cerebus]

Sorry, I must be wearing the wrong glasses becuase I can't make out any of that. 

[mnementh]

...And here's one of the pictures:   

Nessie wearing sunglasses...? 

mnem
Can't be Sasquatch... not furry enough.

[mnementh]

Strangely inaccurate fleabay title "J J Sullivan Resistance Box Type R603". HW Sullivan would be turning in his grave if his decade resistance boxes could be confused with "JJ Instruments" a.k.a "Jay Jay" a.k.a. "JJ Lloyd Instruments" decade resistance boxes.

Ummm... I take it they're like the Hyundai of lab electronics...? 

mnem

at least it's not JJ Walker Instruments... 

[AVGresponding]

The Spectrum Scope arrived yesterday. Well sort of. Pork El Farce decided to leave it at a Post Office instead of my doorstep. Well, ok. It would have been nice if they had left it at the nearest one, which is literally 2 minutes walk from my house and also a local sorting office, but apparently it made more sense to the driver to take it on a 10 minute drive to an obscure and hard to reach village Post Office, where it's just a single counter in a village shop, and with very little space for such things. What a twunt.
The lady running the place was quite relieved I came to pick it up as she'd had to put it in the shed.

The Pork El Farce driver had also done a decent job of trying to destroy the package, though fortunately the seller had done a good enough job that even though the waste of DNA delivering it had managed to thoroughly fuck the outer box, the TE survived thanks to thoughtful and careful packing.

It's a good deal bigger and heavier than I expected, no space to inspect or test it on the bench right now.



As for what counts as on-topic and off-topic here, I'll remind everyone that the title of the thread is "Test Equipment Anonymous (TEA) group therapy thread", and not "Test Equipment Discussion Only". As far as I'm concerned, anything people discuss here that helps them deal with the financial, physical, and emotional distress this addiction causes is fine, with the common sense exceptions of subjects known or likely to cause highly polarised and/or emotional conflicts, such as politics, religion, and the like.

If we want to make it TE only, then technically components, prototyping, pinball machines, and A/V electronics are all off topic. I have a simple method for dealing with "off topic"/posts I'm not interested in; I skim past them.

I believe this thread to be self-policing for the most part, my personal opinion is that Mod intervention isn't really necessary here except on the rare occasions when heads butting together goes past the few posts it should take to either solve differences or agree to not talk about them.

[mnementh]

Hear, hear! 

mnem

I'll direct your attention to the line above regarding OT posts...