Test Equipment Anonymous (TEA) group therapy thread

[Specmaster]

Unless the code has changed recently "whole house" RCD protection, or what we call GFI, is not required.

RCD protection for all supplies at the distribution board is now the norm for UK installations, either new installations or ones modified in (from memory) the last fifteen years. Either an overall RCD + breakers for individual circuits, or an RCBO (combined RCD + breaker) for individual circuits. My place has  an RCD + three breakers for lighting, an RCD + several breakers for wall outlets and a 40A cooker supply, and an RCBO for the supply to the loft (potentially an area with water related faults and I thought it a good idea to have a local supply that could trip without tripping the whole supply).

Conversely here is how my place is set up. In the breaker box: One 100 amp main and 9 circuit breakers. 7 - 15 amp breakers for general lighting/outlets and 2 - 20 amp breakers each supplying one outlet in the bedroom and one in the living room intended for window A/C units. No RCD's. The bath has one outlet which is an RCD outlet. The kitchen has 3 outlets in which one is an RCD outlet and the other two are protected by it.

While we do protect the entire dwelling, the lights and fixed appliances like immersion heaters etc are on a RCD with a sensetivity of 100mA and cookers and sockets are protected by a 30mA RCD. The former is more fire protection and the later for shock protection.

Sent from my POT-LX1 using Tapatalk

[med6753]

In South Australia a "maisonette" is a single building that has two dwellings - separate entrances - separate often separate small gardens - only a common wall or so. The common wall has to extend to or above the roof line for fire isolation.

And that's what we would call a "condo" here.

[Specmaster]

@specmaster: I might take you up on that if you're successful.

Truthfully I'd have liked to cart off the whole lot, but space (in a relatively small terraced London maisonette) tends to keep my acquisitiveness in check. I'd quite like a crack at fixing and using that DC load. Heck, i'd like all those analogue scopes but the space versus "use it will get" factor for analogue scopes mean I'm holding out until I find a nice example of something high bandwidth and relatively compact, say a Tek 2465x. I also could do with a decent 10MHz reference, but that Racal monster is just too many m³/ppb for me.

Well TBH I have no need for either the load or 10MHz ref so if I'm successful then they are yours my friend.

Sent from my POT-LX1 using Tapatalk

[bd139]

If anyone gets that advantest test set and can’t be arsed to fix it, let me know

Metal bashing today. Managed to mount a variable capacitor and reduction drive without fucking it up so far. Miracle.

[med6753]

Unless the code has changed recently "whole house" RCD protection, or what we call GFI, is not required.

RCD protection for all supplies at the distribution board is now the norm for UK installations, either new installations or ones modified in (from memory) the last fifteen years. Either an overall RCD + breakers for individual circuits, or an RCBO (combined RCD + breaker) for individual circuits. My place has  an RCD + three breakers for lighting, an RCD + several breakers for wall outlets and a 40A cooker supply, and an RCBO for the supply to the loft (potentially an area with water related faults and I thought it a good idea to have a local supply that could trip without tripping the whole supply).

Conversely here is how my place is set up. In the breaker box: One 100 amp main and 9 circuit breakers. 7 - 15 amp breakers for general lighting/outlets and 2 - 20 amp breakers each supplying one outlet in the bedroom and one in the living room intended for window A/C units. No RCD's. The bath has one outlet which is an RCD outlet. The kitchen has 3 outlets in which one is an RCD outlet and the other two are protected by it.

While we do protect the entire dwelling, the lights and fixed appliances like immersion heaters etc are on a RCD with a sensetivity of 100mA and cookers and sockets are protected by a 30mA RCD. The former is more fire protection and the later for shock protection.

Sent from my POT-LX1 using Tapatalk

Again...seems different standards. Our RCD's (GFI's) have a trip point of 4 to 5ma. Imagine applying that to the whole house and you'd have a shitload of nuisance tripping. 

[bd139]

Just remember that the RCD/GFI isn’t supposed to prevent you from being killed as such. It’s to break the circuit before irreversible damage is done to you. You’re dead before the RCD pops if you are unlucky either way. Only takes 4mA across the wrong bit in the right conditions. The main thing is to stop the inevitable thing that happened in Brazil a few years back. One guy dug through a buried supply line to his garage and got electrocuted. Cue his wife and kids going to his aid and all suffering the same fate.

Edit: considering taking an amble out tomorrow and visiting this. Not sure I can be arsed or not yet https://westrally.weebly.com/ ... need to get out for a day though so it’s a good excuse

[med6753]

Yep, a current as little as a few milliamps across your heart and you're dead before you even hit the floor.

[Specmaster]

Unless the code has changed recently "whole house" RCD protection, or what we call GFI, is not required.

RCD protection for all supplies at the distribution board is now the norm for UK installations, either new installations or ones modified in (from memory) the last fifteen years. Either an overall RCD + breakers for individual circuits, or an RCBO (combined RCD + breaker) for individual circuits. My place has  an RCD + three breakers for lighting, an RCD + several breakers for wall outlets and a 40A cooker supply, and an RCBO for the supply to the loft (potentially an area with water related faults and I thought it a good idea to have a local supply that could trip without tripping the whole supply).

Conversely here is how my place is set up. In the breaker box: One 100 amp main and 9 circuit breakers. 7 - 15 amp breakers for general lighting/outlets and 2 - 20 amp breakers each supplying one outlet in the bedroom and one in the living room intended for window A/C units. No RCD's. The bath has one outlet which is an RCD outlet. The kitchen has 3 outlets in which one is an RCD outlet and the other two are protected by it.

While we do protect the entire dwelling, the lights and fixed appliances like immersion heaters etc are on a RCD with a sensetivity of 100mA and cookers and sockets are protected by a 30mA RCD. The former is more fire protection and the later for shock protection.

Sent from my POT-LX1 using Tapatalk

Again...seems different standards. Our RCD's (GFI's) have a trip point of 4 to 5ma. Imagine applying that to the whole house and you'd have a shitload of nuisance tripping. 

Those kind of levels are normally used here in labs for single circuit or socket.

Sent from my POT-LX1 using Tapatalk

[Specmaster]

Yep, a current as little as a few milliamps across your heart and you're dead before you even hit the floor.

This is why your advised to do your probing with one hand behind jour back.

Sent from my POT-LX1 using Tapatalk

[Ero-Shan]

Couldn't resist an HP 6296a - in not bad shape - ended up for $ AUD 73, 60V 3A. Down-under prices are pretty high.

My one nasty connection with the national grid (230v) unfortunately gripped my hand onto the DUT and the power - only way I could let it go was to throw the whole assembly (an amp) across the room, the connection point burnt into my left thumb about 3mm, I still have the scar. I have a lot of respect for anything over 60V. Earthing, earth leakage detection, a foot operated 'dead man pedal' (ie take your foot off and the circuit de-powers) are now essential in my book.

What, you had no earth leakage detection at all? [emoji53] Well I sincerely hope that others reading this will now, like you, be getting themselves that level of protection.

Sent from my POT-LX1 using Tapatalk

When I touched 240Vac live with one hand and neutral with another it was ~1973, so domestic breakers were unknown. Fortunately the involuntary contraction of my biceps broke the circuit.

Sent from my desktop using GropeARodent.

Mine was about 1979. We were installing a common aerial for an apartment house. When I tried to measure the signal strength I held the antenna connector in one hand and grabbed the meter's with the other. After realizing what made me drop both, I had to find that in the living room of the dwelling all mains outlets had their earth terminal ("Schutzkontakt") connected to 'live' (or probably 'death') while the antenna was earthed. The elder couple living there never even noticed it.

Back then I accepted an occasional jolt with much more nonchalance than I do now.

[tggzzz]

I've always thought, possibly incorrectly, that a maisonette was a two story dwelling somewhere in a skyscraper. So it is more-or-less a "flat" with an internal private staircase, and the "street level" might be a "street in the sky".

That description would fit, I believe - but am more than open to correction, what our North American cousins would call a 'duplex' in a 'condo' - both terms unheard outside the continent of North America.

Maisonette is almost always used (around these parts anyway) to refer to low-rise buildings. Go beyond two dwellings in one (vertical) building and I'd start talking about a 'block of flats' or a 'flatblock' as some would have it. Maisonette might stretch to more dwellings in some of the older London houses that have been retrospectively converted into upper flats that share a street level entrance and a basement flat with it's own entrance. I think the essence of 'maisonette' is that the envelope of the building ought to fit the idea of 'house' in that locale.

I'm not sure where "there" is, but here a definition (other than "small house") is "An apartment occupying two or more floors of a larger building and often having its own entrance from outside."

Example; note the two storey repeat pattern:


Source: https://www.google.co.uk/maps/@51.4465564,-2.5909768,3a,75y,292.04h,107.67t/data=!3m7!1e1!3m5!1s9tsSLo8OQFjGWJMwVYXp1w!2e0!5s20170401T000000!7i13312!8i6656

[med6753]

Over here that would be called an "apartment complex" or if it's public housing the "projects" or worse yet "the hood"

[Kosmic]

Is it normal for the trace to be so thick (is that what you call it)? I'm an SA noob and this one being a used machine of unknown history doesn't help with knowing what to expect as normal. The cal signal looks reasonable to me.

Lowering the resolution bandwidth (sweep step size) will make the trace thinner. But at the same time it will increase sweep time (slow down the SA). So normally if you want the same reactivity you need to also reduce the span.

Then if you still have some noise you can lower video bandwidth (this is mostly a averaging at the end of the chain just before displaying the data).

Another way is to enable the averaging trace. On newer SA you overlay averaging trace on top of the signal.

Siglent explain the basic better then I do on their web site: https://www.siglenteu.com/application-note/spectrum-analyzer-basics-bandwidth/

Have fun with your new SA and congrats! 

[Kosmic]

I've always thought, possibly incorrectly, that a maisonette was a two story dwelling somewhere in a skyscraper. So it is more-or-less a "flat" with an internal private staircase, and the "street level" might be a "street in the sky".

That description would fit, I believe - but am more than open to correction, what our North American cousins would call a 'duplex' in a 'condo' - both terms unheard outside the continent of North America.

Maisonette is almost always used (around these parts anyway) to refer to low-rise buildings. Go beyond two dwellings in one (vertical) building and I'd start talking about a 'block of flats' or a 'flatblock' as some would have it. Maisonette might stretch to more dwellings in some of the older London houses that have been retrospectively converted into upper flats that share a street level entrance and a basement flat with it's own entrance. I think the essence of 'maisonette' is that the envelope of the building ought to fit the idea of 'house' in that locale.

In french "maisonette" just mean a small house, come from the word "maison" (house). Same idea as Kitchen and kitchenette in English.

[hopski]

This is all very well, but the important thing is how much test gear can you fit into it?

[Kosmic]

This is all very well, but the important thing is how much test gear can you fit into it?

Probably not much I don't recommend it 

[Kosmic]

In term of space the best move I did was to takeover the workshop & storage room in the basement and repurpose the place exclusively for TEA. The room is about 12'x20' with a 9' ceiling. On top of that I got a separate entrance for the basement so 0 problem with SWMBO 

[0culus]

I played around a bit with my new (to me) SA and bg7tbl nose (sic) source. The SA seems to be in really good condition. I was most worried about the front panel because so many Advantest SA have cracked or completely broken off edges. The seller did a great job shipping it.

Quick check of the 30 MHz, -10dBm cal signal. I don't have a short calibration cable, so there's a couple dB loss over the 1m coax.



The noise source is pretty good over the first 500 MHz.



Loses another 5 dB on the way to 1 GHz.



And really takes a dive before it gets to 2 GHz.



Is it normal for the trace to be so thick (is that what you call it)? I'm an SA noob and this one being a used machine of unknown history doesn't help with knowing what to expect as normal. The cal signal looks reasonable to me.

Next question is how to best test out the bandwidth of the scope probes since I don't have those probe-to-bnc adapters.

Looking nice! 

As to the trace width, it's normal for wide spans. As you reduce the span, it will get smaller. My 8568B and 8566A behave the same way.

[med6753]

This is all very well, but the important thing is how much test gear can you fit into it?

Probably not much I don't recommend it 

You would be surprised. 

[mrz80]

... wait for it... yeah, you guessed it, bought ANOTHER FG501 of eBay  . No, really, I can quit any time!

Actually, I misspoke... I got an FG-501A, not another FG-501. It and the JAMMA cable showed up on my doorstep this morning.  It lights up and no smoke!  Siskel and Ebert give it

[Cerebus]

Edit: considering taking an amble out tomorrow and visiting this. Not sure I can be arsed or not yet https://westrally.weebly.com/ ... need to get out for a day though so it’s a good excuse

I could do with a day out too. If I still lived your side of the Smoke I might seriously consider going, but dragging myself across London and then on to Zomerset feels a bit too much like work rather than a relaxing 'day out'.  Shame, we could have worked out some obscure and devilish recognition symbol. A tea-bag loaded 1/4 wave antenna perhaps?

[mnementh]

The irony of that sketch is Cleese has turned into one of them...

Seriously? Have you seen him in interview recently, and seen something I haven't? Every thing I've seen from the man indicates that while he is quite active in political process, he's also pretty progressive in his views.

You Brits and your unique terms. I had to look up "maisonette". That term is unknown here, or at least I never heard of it. And guess what? I live in one! Holy shit!  The next time someone asks about where I live I'll tell them in a maisonette and watch the puzzled looks. 

For the querulous - Maisonette: a flat or apartment with its own (street level) entrance, from the French diminutive for 'house'. I'll bet your lot don't have bungalows either, or verandas.

How does a maisonette differ from a townhouse, then? Yes, we do have both... a bungalow is a small single-story unplumbed house with a finished porch on the main property with only sleeping/dressing quarters; no kitchen and until probably the last 40-50 years or so, no bathroom facilities. These have become a realty class in their own right; now referring to any small, single-story home (fully plumbed of course) which may have a finished attic living space as well.

A veranda is a finished, elevated porch on the main house with a roof of its own; so made as exterior living space that can be entirely screened off in "evil bug" seasons. A proper one will extend around at least two outer walls of a structure, those walls selected against the solar arc so that there is shade available no matter what the season or time of day.

mnem
I actually left this ↓ scene for my wife to find one morning when we first got together. 

[tggzzz]

Edit: considering taking an amble out tomorrow and visiting this. Not sure I can be arsed or not yet https://westrally.weebly.com/ ... need to get out for a day though so it’s a good excuse

I'm going because it is relatively local. I'm not expecting to find anything wonderful, but you never know.

There's the M4/A34 Newbury rally next weekend, but it is in a field not a community centre. http://www.nadars.org.uk/rally.asp

[mnementh]

Yep, a current as little as a few milliamps across your heart and you're dead before you even hit the floor.

This is why your advised to do your probing with one hand behind jour back.

Sent from my POT-LX1 using Tapatalk

"Always be a one-handed electrician." ~ Kirschy

mnem
*Sent by squeezing a hamster really hard*

[tggzzz]

The irony of that sketch is Cleese has turned into one of them...

Seriously? Have you seen him in interview recently, and seen something I haven't? Every thing I've seen from the man indicates that while he is quite active in political process, he's also pretty progressive in his views.

He lives in the Carribean, and tweets that London "is not really an English city any more"
https://www.bbc.co.uk/news/entertainment-arts-48451384