Unconditional stability is a terminus technicus with a precise, fixed meaning.
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That does not look like a voltage reference, does it?
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When I read things a DIY audio I strongly doubt most measure the things they talk about. Getting even a LM317 to work as well as it can takes lots of experiment. Often the PCB one tries to make is harder than a Dead Bug circuit.
I have a floating oscilloscope as I guess many do. At the final stage I hook it up with the real cicuit. Then the fun really starts. What idiot designed TN-C-S safety earthing? Install TT if your country allows it. The USA system is dreadful. If I lived in the USA I think I might request an extra supply and use it's 230V output ( 235 V in the older specs ). Then it becomes one of the best. It would be > 25 kVA if I am right. That should make a nice stiff supply. As far as I know the USA system in much like Norway if used that way. Both use an earth spike as close as possible to the incomming supply. The USA problem is Neutral shift. Not unknown in the UK for other reasons ( Star 3 phase ).
I have a floating oscilloscope as I guess many do. At the final stage I hook it up with the real cicuit. Then the fun really starts. What idiot designed TN-C-S safety earthing? Install TT if your country allows it. The USA system is dreadful. If I lived in the USA I think I might request an extra supply and use it's 230V output ( 235 V in the older specs ). Then it becomes one of the best. It would be > 25 kVA if I am right. That should make a nice stiff supply. As far as I know the USA system in much like Norway if used that way. Both use an earth spike as close as possible to the incomming supply. The USA problem is Neutral shift. Not unknown in the UK for other reasons ( Star 3 phase ).
Do you mean because of the earth and neutral being shared from the sub-station and causing your house earth to be bouncing around above actual earth?
Free electrical power between the incoming earth and local earth, what's not to like?
You've got that right!
When I get back to the lab will show some more experiments with the LM317 -- just don't have the graphs on this laptop.
One way in which too much capacitance can screw up an LM317 is in an attempt to knock down noise through bypassing the ADJ pin -- this results in poor transient performance. TI pointed this out in response to a Nat Semi application note many years ago. Only important for those interested in straightening pins.
No not really. The message in this thread is read the data sheet, and have good reasons for deviating from the suggested circuits. A bigger cap does NOT make everything that much better.
Oh man , there's so much wrong here everything else that follows isn't worth a debate. Just wow.
Yes N. America uses 120 V (115) and 240 V (230) split phase. Earth ground is for safety.
Stiffness is related to the load and branch circuit ratings. Many 120V branches are 20A now. If you were really concerned about high energy mains what in the world are you doing disconnecting safety grounds.
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It would be really interesting if one of y'all with access to them $5,000 analyzers would test the little $10 regulator (LM317 / LM337 +/-1.5V~37V Adjustable Dual Voltage Regulator Power Board | eBay) and report the results!
Funny you say that, It was so bad at college that we could get 6V I was told. We had clean earth in the lab when doing tests. Sadly I never asked Mac how he did it. The railway system is more like the domestic ones now, was called IT. TT also worth a thought. IT used a load resistor to limit current. Being floating it possibly was safer even though on paper it looks the opposite.
Railway systems - IET Electrical
I think a test gig is required,:
A high quality op amp fed by the PS on test.
A friend of mine, while rebuilding an old house that he had inherited,
could light a lamp between protective earth and the plaster that still was wet.
Something must have been awfully wrong there.
But the previous owner did not die from electrical shock.
For a test rig I would say a dynamic range of 136 db or better with at least 1 MHz bandwidth. Here is a very cheap device that used along with a lets say 10 MHz scope could give insights. I used the older version of the Velleman 8 bit scope ( 16 MHz dual ). It could if measuring a reasonably perfected design give enough date. Where it would loose out would be trying to show something in the noise floor against the original signal. Even that can be done if the set up is stable. The Velleman is about £25. To blow it up is 2 x KFC big buckets. I think I will buy one.
Velleman PC Oscilloscope Educational Kit EDU09
Love that story Gerhard.
Velleman PC Oscilloscope Educational Kit EDU09
Love that story Gerhard.
Back in the 60s in the dormitory of my school I had invented the electrolytic heater.
Made from a pan stollen from the dinner service, a welding electrode, this powered between ground and plumbing.
I would caution against spending on a one-channel scope.
There are used analogue scopes around for similar sums.
Stay away from KFC a while long and get a DSO203?
In an office we had some special breakers were fitted due to a very poor earth. The electricity company called SEB came in to upgrade the fuses to the modern type. Doing the best they could they could not meet the safety requirments. They got a very big drill to put in a rod. The Victorian cement was too tough. As a last attempt they said " Nige, redo the earth clamps, it might get a fraction". It was near zero ohms when I did. Someone had clamped onto paint!. Nowadays that clamping to lead pipes it not allowed.
In the same building was a water problem. The owners of the building called SEB in and said inside the problem manhole cover it said Oxford Electrical Company. It was the old Oxford DC system. It turns out SEB were responsible even though no direct link between the companies. If you look up " The Oxford System " it was a blueprint for early UK power. It is said the USA system is adapted 3 wire DC. It's hard to say if that's right. Some houses used the DC wires in what might be called TN-C usually only used in fire risk areas. The cable was lead outside with waxed cotton or paper insulator. My old house had it with 3 wires, lead red black. It was 100% perfect years after installation ( not so when rubber )and possibly 1920's. TN-C is an interesting idea. I suspect it's best of a bad idea. Unlike UK TN-C-S ( also PME ) the neutral and earth continues to the socket on the wall. Real French TT is my prefered one. I think it might continue in the UK as it can be the best idea for farm buildings and is well understood for them.
BTW. A friend who will never eat outside the house will eat KFC. His friend trained with them and said it a very careful company. There is an Urban Myth about KFC that might have caused this. Sorry to say USA our KFC is better. We don't have the dark meat option and what we do have is better. How weird. Others say the same.
I think a soundcard FFT would be better.
In the same building was a water problem. The owners of the building called SEB in and said inside the problem manhole cover it said Oxford Electrical Company. It was the old Oxford DC system. It turns out SEB were responsible even though no direct link between the companies. If you look up " The Oxford System " it was a blueprint for early UK power. It is said the USA system is adapted 3 wire DC. It's hard to say if that's right. Some houses used the DC wires in what might be called TN-C usually only used in fire risk areas. The cable was lead outside with waxed cotton or paper insulator. My old house had it with 3 wires, lead red black. It was 100% perfect years after installation ( not so when rubber )and possibly 1920's. TN-C is an interesting idea. I suspect it's best of a bad idea. Unlike UK TN-C-S ( also PME ) the neutral and earth continues to the socket on the wall. Real French TT is my prefered one. I think it might continue in the UK as it can be the best idea for farm buildings and is well understood for them.
BTW. A friend who will never eat outside the house will eat KFC. His friend trained with them and said it a very careful company. There is an Urban Myth about KFC that might have caused this. Sorry to say USA our KFC is better. We don't have the dark meat option and what we do have is better. How weird. Others say the same.
I think a soundcard FFT would be better.
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"Living at the limit"
"Living at the limit"