Test Equipment Anonymous (TEA) group therapy thread

[BU508A]

I just used for the first time a

Code: [Select]

lambda *args, ... : 
in Python. It works but I do not fully understand why, was a copy&paste try from the web... 

Because Python is a copy & paste programming language ... 

[tggzzz]

I just used for the first time a

Code: [Select]

lambda *args, ... : 
in Python. It works but I do not fully understand why, was a copy&paste try from the web... 

Because Python is a copy & paste programming language ... 

... provided the copied source is indented to the same extent as the destination.

I hate languages where the amount of whitespace is semantically important. It is too easy to introduce subtle problems, and a prettyprinter cannot - by design - help.

Ditto type of whitespace, e.g. tab vs space in makefiles 

[BU508A]

I just used for the first time a

Code: [Select]

lambda *args, ... : 
in Python. It works but I do not fully understand why, was a copy&paste try from the web... 

Because Python is a copy & paste programming language ... 

... provided the copied source is indented to the same extent as the destination.

I hate languages where the amount of whitespace is semantically important. It is too easy to introduce subtle problems, and a prettyprinter cannot - by design - help.

Ditto type of whitespace, e.g. tab vs space in makefiles 

So, therefore you are not a fan of this language?   

[tggzzz]

I just used for the first time a

Code: [Select]

lambda *args, ... : 
in Python. It works but I do not fully understand why, was a copy&paste try from the web... 

Because Python is a copy & paste programming language ... 

... provided the copied source is indented to the same extent as the destination.

I hate languages where the amount of whitespace is semantically important. It is too easy to introduce subtle problems, and a prettyprinter cannot - by design - help.

Ditto type of whitespace, e.g. tab vs space in makefiles 

So, therefore you are not a fan of this language?   

There are some people I would actively encourage to use that languages. Others wouldn't need encouragement

[Specmaster]

<snipity snip>



Okay... but did you confirm with a meter that hot and neutral were in fact wired correctly; not neutral to the switch and hot/neutral swapped at the pin header on the PCB?     This is clearly marked on mine, as you can see in the pic above.

Also, the power cord on mine is properly grommeted, as you can also see above; they just plastered the hot snot on it because these particular grommets are for a 1/8" thick panel, so tend to shift a wee bit on this 1mm thick painted sheetmetal. it looks like they did the same on the cord for your handset, quite likely for the same reason.


@bd139 - Sure, but I'm reasonably certain even a certified bastard like you wouldn't use yellow w/green stripe for any power conductor. 

mnem
Electrons may be very very small... but when they gang up on you, they always win.

Of course, I checked that the switch was indeed in the "hot" wire and also that the other mains cables were also correct polarity wise, what else did you expect a pro to do  I noticed that yours had a fuse fitted, something mine doesn't have though and I may have to retrofit one                                                                                                         

[bd139]

@bd139 - Sure, but I'm reasonably certain even a certified bastard like you wouldn't use yellow w/green stripe for any power conductor. 

No comment 

[Saskia]

after a little rant on Saturday I received an email from Media Markt that they will take back flight simulator for a refund. Seems that they contacted microsoft about it and conveyed my sincere displeasure.

[dl6lr]

After discovering how well & truly fooked this thing was, I've gone back & rewired with a new cord in North American color code. Handset GND restored to original direct to Earth GND configuration after seeing inside of handset and noting close proximity of heater element to metal shell.

[nitpick]
You still have a quirk inside your wiring: It is not allowed to (re-)use a mechanical connection to act as an electrical ground bonding. So you have to use a separate ground connection to the case instead of the mounting bolt of the board. Yes, the chinese forgot about this as well...
[/nitpick]

Bernd

[med6753]

Remember when I said no more TEA until after Christmas? And I also stated I was specifically looking for a Type 515A? Well, forget all that. I lied.  A Type 503 landed on my radar so I tossed out a bid. I won. Should have it next week. Seller sez in the header of the listing for parts or not working but in his detail states it's fully functional. We'll see.

The Type 503 is the same size and form factor as a Type 515 but has lower B/W and differential inputs.

This is not the actual unit. Just a stock pix.

 

[BU508A]

There is a 515A in the US...



And a 515A here in Germany ...

[mansaxel]

And in Yoorp, most plugs of the "19mm between pin centres" family are non-polarized; the exceptions being Switzerland, France and Denmark. Which means that every appliance is a death-trap, right?

Alternatively, one can build appliances so that it does not matter which is which. 

:poke:

Well, not all of Europe has round pin plugs. Not all NA plugs are polarised either. That aside, while non polarised mains connectors do not make an appliance a death-trap, they are not as safe as a polarised one with fuse and switch in the live.
In countries were polarised plugs are standard and wires colour coded, there is no excuse for not following the standard.
While most on here know why, for visitors, the issue is that if the neutral is fused or switched, with fuse blown all the internal mains parts are live with respect to ground. Two fuses don't help because you don't know which will blow.  Any un-polarised device should have at least a double pole switch or the same applies when switched off. Note this mostly applies to items intended to be serviced, permanently sealed devices like power supplies and chargers should not have internal connections exposed.

I _did_ actually specify so as to exclude BS 1363    and the Danish, Swiss and French plugs all have an orientation, but for instance the CEE 7/7 plug (which is a French-German hybrid) can go into both a French and a German outlet and the question of which pin carries which leg is totally arbitrary. Same with C13/C14 pairs. Those might very well be fed from a Schuko plug (that's what happens in more than 90% of cases, I guess) and then polarity is a toss-up.

My expectations are;

• Device shall be safe with covers on.
• Both neutral and phase are mains-bearing live parts and are dangerous until proven different.
• If a device is less safe with the plug flipped in one direction than in the other, it is a defective device which requires repair.
• When covers are off, in essence, all bets are, too.
• Notwithstanding above, it's of course nice if one doesn't stumble on live terminals inside the box.
• Not assuming the worst case per above will see you off with a loud bang, which at times can be permanent.

[med6753]

Yea, $200 USD for the scope AND $240.64 shipping.    And I checked, that's what the seller wants for shipping. They are nucking futs. 

[mnementh]

after a little rant on Saturday I received an email from Media Markt that they will take back flight simulator for a refund. Seems that they contacted microsoft about it and conveyed my sincere displeasure.

Obviously, your reputation precedes you... or perhaps it was your established history with explosives and model rocketry.

mnem
Saskia brings a whole new meaning to the phrase "Reach out and touch someone..." 

[Ice-Tea]

Re: color coding mains. I have a simple rule: assume nothing. Measure everything.

[mnementh]

    Okay... but did you confirm with a meter that hot and neutral were in fact wired correctly; not neutral to the switch and hot/neutral swapped at the pin header on the PCB?     This is clearly marked on mine, as you can see in the pic above.

Of course, I checked that the switch was indeed in the "hot" wire and also that the other mains cables were also correct polarity wise, what else did you expect a pro to do  I noticed that yours had a fuse fitted, something mine doesn't have though and I may have to retrofit one 

Sorry... was just making sure. What with all this back/forth anal-ness over color codes for electrons that cannot see, I wasn't positive that teensy little issue hadn't gotten lost in the noise. 

Check the back where the cord plugs in; it looks like yours may be one of the ones with an embedded holder for 4mm x 20mm size fuse. That jumper on the back is usually the giveaway, even if it is hard to see from the outside with the cord plugged in.

mnem

[mnementh]

I just used for the first time a   

Code: [Select]

lambda *args, ... :     in Python. It works but I do not fully understand why, was a copy&paste try from the web... 

Because Python is a copy & paste programming language ... 

... provided the copied source is indented to the same extent as the destination.   I hate languages where the amount of whitespace is semantically important. It is too easy to introduce subtle problems, and a prettyprinter cannot - by design - help.   Ditto type of whitespace, e.g. tab vs space in makefiles     

So, therefore you are not a fan of this language?   

There are some people I would actively encourage to use that languages. Others wouldn't need encouragement

So...    for no-Kung-Fu motherfuckers like me then...? 

mnem
I am to coding as Benny Hill is to comedy: A blunt instrument best used in small doses, as infrequently as possible.

[mnementh]

@bd139 - Sure, but I'm reasonably certain even a certified bastard like you wouldn't use yellow w/green stripe for any power conductor. 

No comment 

Of course, one would not expect bd to undermine his bastard-ness with any other response.   

mnem
*a dwagon in wolf's clothing*

[mnementh]

After discovering how well & truly fooked this thing was, I've gone back & rewired with a new cord in North American color code. Handset GND restored to original direct to Earth GND configuration after seeing inside of handset and noting close proximity of heater element to metal shell.

[nitpick]   You still have a quirk inside your wiring: It is not allowed to (re-)use a mechanical connection to act as an electrical ground bonding. So you have to use a separate ground connection to the case instead of the mounting bolt of the board. Yes, the Chinese forgot about this as well...   [/nitpick]   Bernd

Yeah, I considered this myself; however, I'm a lot more worried aboot the fact that the safety GND to the handset is only a single 22ga wire.   

Sometimes, you have to make concessions to reality; for my own peace of mind, I did solder that 22ga wire to the main GND wire right at that eyelet. 

mnem
 

[mnementh]

At least in NA, there are conventions we follow because not all electrical widgets have a grounded cord; we wire everything the same way with respect to Neutral vs Line as our plugs are polarized with an extra-wide Neutral prong & slot to act as if there was an actual GND as applicable. Neutral connects to Earth GND at the same bus in the breaker box, and is supposed to remain a single unbroken conductor all the way to the load; it is never switched.

And even then the conventions are fooked!  All new ungrounded cords have polarized plugs, with one exception.  All new strings of christmas lights use non-polarized plugs, where neither prongs nor slots are extra-wide.  That appears to be no big deal, until you need a 2m extension between two strings of lights.  The polarized prong of the extension cord will not fit into the slot of the christmas lights.  I have spent an excessive amount of time searching for non-polarized extension cords, which appear to be no longer available (I have one, but have no idea how old it is).  I have spent an equal amount of time searching for polarized christmas light strings, which also appear to be no longer available (I actually have one, but have not put in the time looking for the fault in the LEDs or other part of the string).

There is another option, but is excessive consumerism.  That is to run a long extension cord in parallel with the first set of christmas lights and then use a power bar at the source.  That is totally not necessary, if the convention, as the dragon described, was actually followed.

Of course, this is discovered when the outdoor temperatures are now dropping to -10 C.

/rant

That's deliberately to keep 1D10Ts from being able to plug anything other than a string of lights into a string of lights. There are special regulations for temporary holiday lighting to prevent them being used for anything other than temporary lighting according to instructions. No plugging in of toasters, drills, dishwashers, etc... 

It also keeps those Darwin Award candidates from being able to plug 3 strings of lights into an extension cord plugged into a string of lights plugged into another string of lights, each of those with 2 or 3 strings of lights in series... outlet strips are enough of a hazard in and of themselves, as they encourage tower-o'-plugs stacking contests like this. 

Don't laugh... newspaper archives are full of tales of morons using Xmas lights as an extension cord. 

mnem
 

[tautech]

Dropped this here before...our off grid data link and data relay point serving the community connectivity needs:



From another angle



In doing so probably mentioned another site nearby that links to the lowest small dish above but provides coverage into other areas.
It's only a couple of km away:



It's been active for a year now and being over there a couple of days back was a good opportunity to grab a few pics.
It was an abandoned CB/RT relay site and as technology has moved on from when it was originally installed and cell coverage was in its infancy here, anyway a few years back the untreated timber pole blew down in a storm however the concrete tank bunker and its solar panel frame and wind turbine were still salvageable so were put to good use. 

5 GHz Point to Point data provision is what it does now with the backhaul to our main relay site that's now 11 GHz backhaul provisioned and been operating for an additional few months. Bottom dish provides the backhaul to our main site.

New pole and HW looking in the general direction of our primary site:


The wind turbine is getting on and most info on it is illegible however there is a faint 100W rating and under no load some 18V is produced therefore we've deduced it's a 12V 8A turbine and engineered around it as such.
The single 320W solar panel and it's mounting HW is new however the galv pipe frame atop the bunker was existing and therefore reutilised although a good few rusty bolts were replaced with stainless. 
At this time the single solar panel and wind turbine are managing very well and although we provisioned mounting for 2 panels I doubt if it will be used. More on this later.



A peek inside and the panel hides a pair of 12V 195AH SLA's connected in parallel for just a 12V system whose load is the external pole HW via the POE switch. A charge controller for each energy source.



This solar stuff is pretty impressive and in both installations it's the primary source of energy however what just one 320W panel can do fair blew my socks off a year ago when I remotely snapped this screenshot of the solar controller of what was then a spanking new installation. Just a second faster on the snap and it would show 20A ! 

[kleiner Rainer]

And now to something completely different.

I scored a pH/mV-meter made by Knick in Berlin about 1972/73, thanks to fellow eevblog member jogri.

After a bit of cleaning, it looks very good for its age, and it works as expected. I included a 9V block as a size reference.



Since pH sensors are extremely high impedance voltage sources, the meter has a very high input impedance. The connector is a special coaxial connector, DIN 19262, but you can use 4mm plugs: in fact, DIN 19262 is a shielded 4mm plug!

I checked the internals, and the circuit board in the center is a sort of reference, with 1V and 2V outputs. Filtering for the power supplies is with MIL-quality hermetic Tantal caps, so no need for replacement.

The meter movement is a big Gossen Fe 1, 350uA full scale, the window size is 150x70mm. This alone would have been worth the price I paid, but as a working unit, its a steal. I intend to use it as a bridge null sensor and mv meter ( ranges +-35, 140, 350 and 1400mV FS). It also has a recorder output, so connecting it to a computer would be possible via an A/D card.

jogri asked Knick for documentation, but 50 years later they have nothing left. Anybody out there with old Knick or chem lab equipment catalogs from the seventies?

Greetings,

Rainer

[Robert763]

Yea, $200 USD for the scope AND $240.64 shipping.    And I checked, that's what the seller wants for shipping. They are nucking futs. 

And to the UK  $1,658.04 UPS Worldwide Saver 

[cyclin_al]

At least in NA, there are conventions we follow because not all electrical widgets have a grounded cord; we wire everything the same way with respect to Neutral vs Line as our plugs are polarized with an extra-wide Neutral prong & slot to act as if there was an actual GND as applicable. Neutral connects to Earth GND at the same bus in the breaker box, and is supposed to remain a single unbroken conductor all the way to the load; it is never switched.

And even then the conventions are fooked!  All new ungrounded cords have polarized plugs, with one exception.  All new strings of christmas lights use non-polarized plugs, where neither prongs nor slots are extra-wide.  That appears to be no big deal, until you need a 2m extension between two strings of lights.  The polarized prong of the extension cord will not fit into the slot of the christmas lights.  I have spent an excessive amount of time searching for non-polarized extension cords, which appear to be no longer available (I have one, but have no idea how old it is).  I have spent an equal amount of time searching for polarized christmas light strings, which also appear to be no longer available (I actually have one, but have not put in the time looking for the fault in the LEDs or other part of the string).

There is another option, but is excessive consumerism.  That is to run a long extension cord in parallel with the first set of christmas lights and then use a power bar at the source.  That is totally not necessary, if the convention, as the dragon described, was actually followed.

Of course, this is discovered when the outdoor temperatures are now dropping to -10 C.

/rant

That's deliberately to keep 1D10Ts from being able to plug anything other than a string of lights into a string of lights. There are special regulations for temporary holiday lighting to prevent them being used for anything other than temporary lighting according to instructions. No plugging in of toasters, drills, dishwashers, etc... 

It also keeps those Darwin Award candidates from being able to plug 3 strings of lights into an extension cord plugged into a string of lights plugged into another string of lights, each of those with 2 or 3 strings of lights in series... outlet strips are enough of a hazard in and of themselves, as they encourage tower-o'-plugs stacking contests like this. 

Don't laugh... newspaper archives are full of tales of morons using Xmas lights as an extension cord. 

mnem
 

However, adding a gazillion 45 strings  to the same outlet is actually encouraged.  See the box image! 
I get what you are saying; it makes sense to do something different for temporary lighting convention.
However, I wish they would stick with one convention and provide at least some options for extension cords compatible with temporary lighting.

In my case, the roof line changes in the middle of the house.  I would like to connect only 2 strings of lights, but there is 6' distance between the end of the high roof section and the end of the low roof.  That short distance is largely protected under eaves and mostly out of sight.  The ideal solution would be a 6' non-polarized extension cord.  It looks like the so-called proper solution is a 50' (36' needed but not available for purchase) extension cord with a power bar hanging out where it is exposed to the weather (too bulky to tuck it up where there is protection from weather).

The 1D10Ts are somewhat imaginative and will go to great lengths to avoid spending money or even doing it remotely safely.  Conventions are not going to stop them.
Facing a similar situation, my guess is those who live around this area will just chop the connectors off both the light strings and extension cords and twist the bare ends together.  Electrical tape would be considered optional     No, I do not have the time to join the volunteer fire department ... it would be another full time job (the local statistics are alarming).

I find it frustrating since I see an obviously safer configuration in comparison to using the proper parts that are available...

Edit: forgot to add the image

[Cerebus]

The standard solution for temporary lights and the like in the UK has always been these:



made by MK Duraplug. I don't know whether they conform with some official standard pattern (they obviously comply with official safety standards) but they are a defacto standard in the UK for outdoor mains extensions for lights, tools, mowers and the like.

[mansaxel]

The standard solution for temporary lights and the like in the UK has always been these made by MK Duraplug.

My parents somewhere have a book written 1965 by a swedish newspaper correspondent to the UK, in which he looks at pretty much everything in the expat life. One of the things he mentions is the need to gather a veritable menagerie of mains adapters if you're bound to as correspondents are to change homes now and then, since BS 1363 had not permeated as much as it has now, then.

I suppose it also is the reason this little device exists:



I cherish mine. It's such a convenient mains applicator. Do note that it does not care which is which and breaks both conductors.