Test Equipment Anonymous (TEA) group therapy thread

[BU508A]

EDIT: @BU508A, the plugtop should have the fitted fuse size displayed on it. Moulded plugs also often have a window in the fuseholder that allows you to see the colour of the fuse.
This partially helps, as 13A are brown, 3A are red, but unfortunately, 1A, 2A, 5A, and 10A are all black...

Good grief, I think I edited this post half a dozen times   

What?     

Seriously? Who has designed this? A Monty Python Flying Circus workshop?   

[Cerebus]

You Brits and your ring circuits. Totally non-Kosher and would never fly here. 

Yet the statistics bear out our approach. Most recent annual statistics for UK domestic fires from malfunctions of fixed wiring 2152, USA 24,100; adjust for population difference (66,435,550 versus 329,968,629, ratio 1:4.996) gives: UK fires 2152, US adjusted 4852. Two and a quarter fires from US fixed wiring malfunctions for every one in the UK on a population adjusted basis. So, now who's kosher and who's treif?

[Cerebus]

And how do you distinguish between a cable with a 3A fuse and a 13A one? If you are going to use the wrong cable, then either it blows the fuse, or, the fuse doesn't really make sense imho.

The fuses are colour coded. You set the fuse to the rating of the cable that is on that plug, and obviously the cable should have a rating equal or higher than the connector on the other end (e.g. IEC connector). The fuses are there to protect the cable, not the equipment. The equipment should have its own appropriately rated fuse.

[bd139]

Edit: interesting. White, economy version of the MSO5000:

The white would be a welcome relief. Experience has now taught me that the black MSO5000s are hell to find a control on if it's one that has not yet become part of your 'muscle memory'.

That said, a couple of weeks with the scope and I'm liking it. The only time I'm less than fully chuffed is when using the horizontal position control (and to a lesser extent vertical position an trigger level controls), the laggardness makes you wonder whether you're turning the knob the right way. I'd quite like the features of this scope with a nice multi-tone grey HP scope appearance and instant UI response of the HP 546xxx era.

Yes the black instruments are horrible. They are only effective if they light up like a christmas tree (like my keyboard) I find. Also it's slightly depressing staring into the depths of lots of black instruments all day.

546xx series felt like an analogue. Lovely scopes. Totally agree. I used an MSO5000 at the Telonic stand and it felt like my DS1054Z. That's not end of the world but yes it would be nice if it was a bit faster

[mansaxel]

I never get used to this concept of the fuse in the plug. Is that really that helpful? 

With ring-mains it sort of becomes necessary.

[med6753]

I think your "stats" fail to take into account a few things.

First, we were the first country to electrify. Many residences have OLD wiring, including "knob and tube" wiring. Ever see that stuff? Scary.

Second, higher average currents due to fact that we stayed with 120V/60Hz.

Third, the numb nuts that decided aluminum wiring in residences would work.     

[bd139]

I think your "stats" fail to take into account a few things.

First, we were the first country to electrify. Many residences have OLD wiring, including "knob and tube" wiring. Ever see that stuff? Scary.

Second, higher average currents due to fact that we stayed with 120V/60Hz.

Third, the numb nuts that decided aluminum wiring in residences would work.     

But your plugs... national American passtime:



 

[med6753]

I think your "stats" fail to take into account a few things.

First, we were the first country to electrify. Many residences have OLD wiring, including "knob and tube" wiring. Ever see that stuff? Scary.

Second, higher average currents due to fact that we stayed with 120V/60Hz.

Third, the numb nuts that decided aluminum wiring in residences would work.     

But your plugs... national American passtime:



 

That too! 

[BU508A]

And how do you distinguish between a cable with a 3A fuse and a 13A one? If you are going to use the wrong cable, then either it blows the fuse, or, the fuse doesn't really make sense imho.

The fuses are colour coded. You set the fuse to the rating of the cable that is on that plug, and obviously the cable should have a rating equal or higher than the connector on the other end (e.g. IEC connector). The fuses are there to protect the cable, not the equipment. The equipment should have its own appropriately rated fuse.

Yes, I understand this. But what I am curious about is: how does every Tom, Dick and Harry to get on with this? Does it happen, that soembody is whacking a 10A fuse into a 1A rated cable because they are all black and/or the proper fuse wasn't available? I do not expect that anybody here in this forum will have any problems at all to handle this correctly.
But for safety reasons it should also get on with the more "average" part of the people.

[mansaxel]

But your plugs... national American passtime:



 

That too! 

It's an excellent example of technical debt.

[Cerebus]

But your plugs... national American passtime:

Let's not get into American but plugs, it's bad enough with your Bronies and Furrys.

[BU508A]

But your plugs... national American passtime:



 

Yummy! Burning Polyvinylchloride! Excellent stuff, gives a good taste to that poor little marshmallow. 

[bd139]

But your plugs... national American passtime:

Let's not get into American but plugs, it's bad enough with your Bronies and Furrys.

 

[tggzzz]

I think your "stats" fail to take into account a few things.

First, we were the first country to electrify.

Even if true, the time difference was insignificant..

Many residences have OLD wiring, including "knob and tube" wiring. Ever see that stuff? Scary.

Ever seen wooden insulation? Take single insulated wire and lay it in wooden channels like this:

Code: [Select]

wwwwwwwwwwwww
w e w l w n w
wwwwwwwwwwwww
where w is wood, e l n are single-insulated wires.

Even worse, ever seen lead insulation? Imagine lead-sheathed two-core cable, where the lead is the earth. Now imagine making a joint between three such cables. Shudder.

I've seen both under the floorboards of a house, neither in use

Second, higher average currents due to fact that we stayed with 120V/60Hz.

Third, the numb nuts that decided aluminum wiring in residences would work. 

We avoided those idiocies.

[Specmaster]

What sort of frequency range or ranges do you need? Added a link to a semi look at my little toy above too.

Only need HF < 30MHz.

Problem solved. TE budget dented . Scenes around here:



Decided to nab a Rigol DG822. Fine for this uncracked but it can be unofficially frigged into pretending it's a 100MHz DG992 if I need that in the future.

Plus honestly I have no signal sources which is turning into a pain in the arse at the moment.

You keep going back to a Rigol, it seems to be an ever lasting circle of life with you and Rigol locked in a love / hate relationship, you need a nice Marconi or HP unit.

[tggzzz]

I never get used to this concept of the fuse in the plug. Is that really that helpful? 

Yes it protects the lead. So if the IEC lead or inlet goes short or faults it blows the fuse rather than gives you a nice smoky cremation off the cable

And how do you distinguish between a cable with a 3A fuse and a 13A one? If you are going to use the wrong cable, then either it blows the fuse, or, the fuse doesn't really make sense imho.

When the modern standard 13A plugs and sockets were introduced:

• most leads were permanently attached to the equipment; detachable IEC leads are a modern invention
• the leads frequently used rubber insulation and were fabric covered. Perished/kinked leads were far from unknown

AFAIK, the use of fused plugs is to protect the house, not the lead, not the equipment. If the equipment or lead develops a fault, the fuse gets hot and blows before the house wiring gets hot and catches fire under the floorboards.

[bd139]

You keep going back to a Rigol, it seems to be an ever lasting circle of life with you and Rigol locked in a love / hate relationship, you need a nice Marconi or HP unit.

The Rigol units are pretty good - I honestly like 'em. I'm mostly just "renting" them by buying one when I need one and selling it when I don't as they don't depreciate a lot due to the high demand and idiots on ebay. This has an aggregate lower TCO (~£5/month) than owning a Marconi or HP unit as they are (((RF -or- function generators) -and- unreliable) -or- bloody expensive)  . Also if you do this it minimises failure risk outside warranty and your entire capital getting wiped out in one go.

Plus you get to open new shiny things regularly 

[Cerebus]

Yes, I understand this. But what I am curious about is: how does every Tom, Dick and Harry to get on with this? Does it happen, that soembody is whacking a 10A fuse into a 1A rated cable because they are all black and/or the proper fuse wasn't available? I do not expect that anybody here in this forum will have any problems at all to handle this correctly.
But for safety reasons it should also get on with the more "average" part of the people.

In practice it seems to work out OK. Cables come with the right fuse out of the box. Standard consumer advice is "always replace the fuse with one of the same value".

If the worst comes to the worst, and someone sticks a 13A fuse on a 0.50mm² 3A rated cable then, yes, it is technically risky. However, by far  the commonest fault is not a cable being run too hot, but a simple short in the cable from fraying, bending damage and so on. In the event of that kind of fault a 13A fuse is going to blow well before the cable can heat up appreciably.

Even running the cable too hot the risks aren't catastrophic. From memory, the standard ratings are for a 50ºC rise. So, a 3A cable run at 13A is going to (crudely) have a rise of 216ºC over ambient, say a final temperate of 236ºC. Not enough for spontaneous combustion in all but the most hazardous environments, but enough for the insulation to melt, the conductors touch, short and blow the fuse anyway.

So, yes, there are shortcomings in that it is possible for the wrong fuses to be used. But, it's better that they are there and offering protection in the majority of cases, than they are absent and protection falls back to the distribution board fusing which will be at least 16A.

[Specmaster]

Just replaced two sockets in my place. One of the cheap shit ones that has been in there since I moved in wasn't smelling too good.  Cracked it open and it smells awful inside. Looks like plug contacts have been arcing which is shit as all it had was an XB one and a laptop plugged into it. Have put some MK ones in instead.

Yep, MK, Crabtree or Ashley sockets are perfectly OK as they all treat the BS standards as a base platform to build upon rather than a target to reach. Arcing like that is not very conducive to successful operation of a amateur radio either, it must have been causing some reasonable interference which was not only mains borne but using the internal wiring of the house as an antenna which may interfere as well.

[Cerebus]

We avoided those idiocies.

Not entirely. There was a brief flirtation in the UK post WWII with aluminium domestic wiring. We quickly realised it was a stupid idea after the first few fires and promptly banned it.

[Specmaster]

Just replaced two sockets in my place. One of the cheap shit ones that has been in there since I moved in wasn't smelling too good.  Cracked it open and it smells awful inside. Looks like plug contacts have been arcing which is shit as all it had was an XB one and a laptop plugged into it. Have put some MK ones in instead.

Are you talking about mains connectors?    What is a "XB" and what is a "MK"?

Yes. Sockets.



XB is me being lazy. XBox

MK is manufacturer of UK electrical stuff like plugs, sockets etc. http://www.mkelectric.com/en-gb/Pages/default.aspx ... reasonable quality items. Think I paid £4 each for two of the sockets above from RS. Apparently still made here it said on the pack

They are indeed still made here in the UK and a few years ago I worked for both of their major competitors, first, Crabtree and I had the distinction of being (so I was told by MK) of being the only  employee of a competitor who was a regular and welcome visitor who actually got to go inside and all over their various factories in the UK. I was in the industrial controls section of Crabtree and MK used their controls on their production machines, hence I had access inside their factories. Then a some years later I worked for Ashley. AFAIK only MK and Crabtree are still UK made, I think as Ashley was acquired by Hager about 20 years ago, they moved production to the far east, maybe China but I'm not 100% certain.

[bd139]

Getting crazy here today

https://www.ebay.co.uk/itm/124108537988

[mnementh]

You are weak to my dork side enabling powers 

Don't get too wrapped up in your "abilities"....   (I've had a foot in that shadow since I was 8 )

*Waves hand dismissivlely*  "These are not the BM-800 studio unidirectional electret condenser microphone with pop filter and  suspension boom scissor arm kits you are looking for..." 

Windoze10 finally has USB headset integration down pat; once installed for the first time, it switches over to the USB headset (and mic) every time quickly & reliably just as if you'd plugged in a regular analog headset. It even keeps track of volume, EQ, spatializing & gain settings for each headset independent of speakers, the table mic, and other headsets.

If I plug in my headphones before I launch Discord, it will ask if I want to use the gaming headset mic or the tabletop mic which is usually plugged in but muted. I dislike the attack delay (I have a pretty low timbre to my voice, and it just won't recognize it reliably on the auto-mute) for both hot mic and muted, so I just use the default [ESC] PTT hotkey; it ONLY works as the hotkey when Discord is my foreground window/active tab. I usually use the table mic whether on speakers or headset; sound quality is clearer, especially with my voice.

You can adjust all these Discord Voice Settings, and test your mic with Discord, by clicking the little SETTINGS gearstar symbol in your user applet when it pops up after you connect to voice-chat.

mnem
 

In the interests of preventing everyone's ears from having to endure the deafening sound of my 5.1 sound system howling pickup on the mic (because of speaker positioning and size of room, I find it also most impossible to avoid) I have dropped some cash on one of these https://www.amazon.co.uk/gp/product/B06XX7SYP2/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1 which  seems to have everything sown up as far compatibility with all of my PC's. Hope that these will work OK for this Sat's session. 

Not sure about the sound quality from those; I expect they'll be a bit like these:

A lot of cheap Chinesium Dogespeak in that ad, for sure;  about them is patented...? The dongle/analog headset form factor is how ALL gaming headphones used to be made; the big heavy wart in the middle of the wire just sucks bunge.

I have a few "minimum" criteria for any headphones I use regularly:

1) NO "bump in the wire" wart-type dingus. FOR ANY reason.   
2) MUST have oversized closed earcups big enough to go around my ears and seal against my head. All the active noise-canceling bundahoo in the world doesn't hold a candle to a nice, tightly-sealed closed earcup.
3) MUST have minimum 40mm drivers, preferably in a 2-way driver arrangement.
4) No boom mic, or one that by default folds up tight against the headband. I break those fuckers left and right because klutz with Shrek-hands.
5) Padded headband for my bald haid. Fellow eggheads will get this; normies can go... suck a egg. 



These are what I'm using now. I got them because they were only $7 at the Thrift, and by feeling in the earcup, I could tell they had 35mm drivers. I ALMOST put them back, but tried them on and decided to keep them for the price and the excellent comfort; aside from the drivers, they ticked all the other boxes on my list very nicely.

Later online research showed they were SteelSeries' budget offering; MSRP $60 and street price of $40-ish when I got them. A few pleasant surprises found after-the fact are why I kept them:

1) Still supported by the MFR 6 years after release. SteelSeries Engine software still supports the headset, so you can tweak sound profiles and lighting (the sedately colored rings on the earcups) to your heart's content. If I could be arsed, I could probably tweak the mic to make it sound as good as my Labtec table mic, but meh.

2) Remarkable comfort after hours of use, even with budget fabric cushioning. Headband tension is medium-medium high; enough that I could wiggle my fat arse around "dancing" while listening to streaming music and they didn't fall off my shaved head, but not tight enough to crush my ears.

3) Left earcup has mic MUTE toggle button that is both intuitive to use and reliable. It just works. 

4) 100% functional with default Windoze drivers. If you don't care to fuck with sound/lighting profiles, plug it in and it just works. Unplug it and your PC goes back to exactly the way it was.

Bottom line: based on my experience with this budget model from SteelSeries, I would definitely keep them at the top of my list if shopping higher-priced models. They have a much-better-than-average handle on what features folks using a headphone on a PC need, and they sell on features & quality design, not bundahoo .

mnem

[Specmaster]

Just replaced two sockets in my place. One of the cheap shit ones that has been in there since I moved in wasn't smelling too good.  Cracked it open and it smells awful inside. Looks like plug contacts have been arcing which is shit as all it had was an XB one and a laptop plugged into it. Have put some MK ones in instead.

Are you talking about mains connectors?    What is a "XB" and what is a "MK"?

"XB" - dunno.

"MK" - the commonest UK brand of reasonable quality electrical fittings. Plugs, sockets, switches, contactors, distribution boards etc. Acceptable quality but my old sparky friend swears by Crabtree - equal or better quality and better price.

Your spot on, they were better, MK used to use a 10% batch test for their quality control as they were assembled by machines, but Crabtree used hand assembly and there were about 6 or 7 women in a team assembling them and each lady did a specific part of the build and passed it onto the next lady in the process, who checked, the firsts work before doing hers and then passing it on again the next lady and so on until the completed item was built. Then it was a 100% test of the complete units for continuity, switching action, and each pin of a plug is tested on the socket to check its retention pressure and a flash test would be done and then 10% would be taken away to another test bed where the units would be subjected to load tests and terminal temperature rise tests.  If more than 1 failed, the remaining 90% had to go through the extended tests, the rejects taken out and the ones that passed were then sent to the packing stage, where they were packed with a pair of fixing screws and sealed in their own plastic bags.

So your friend was quite right, they were better quality and also, even despite all the manual labour, better priced. This was true of all Crabtree products and hence why even MK used their industrial controls and commercial circuit breakers in their own factories.

[Zucca]

Getting crazy here today

https://www.ebay.co.uk/itm/124108537988

Can't be true.