And by the way, every time you mention your dislexia, something triggers in my brain and I start hearing the old Hollies hit "He Ain't Heavy, He's My Brother".
It would probably bother some people, but with you, it just adds a bit more colour to your rainbow. Don't waste time on trivia of no consequence. Think back and try to remember any one time we didn't understand each other. I'll wager there was none.
It would probably bother some people, but with you, it just adds a bit more colour to your rainbow. Don't waste time on trivia of no consequence. Think back and try to remember any one time we didn't understand each other. I'll wager there was none.
Common as muck we Pearsons, Petrovic. I should have known. All the North Sea countries have Pearsons.
Dyslexia is a fair trade. I use that bit of the brain to do engineering. I only realized in later life other people can not picture objects in their heads the way they do words. A very fair trade as my computer tries hard to let me know when I am wrong. I thought Beetle and Beatles was good for me in the same paragraph.
Dyslexia is a fair trade. I use that bit of the brain to do engineering. I only realized in later life other people can not picture objects in their heads the way they do words. A very fair trade as my computer tries hard to let me know when I am wrong. I thought Beetle and Beatles was good for me in the same paragraph.
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That might be a little bit of Low Latent Inhibition mixed in there, too. I used to think I was crazy until I read about it.
Many of the best power supplies ever made (Lambda) are essentially a 723 and a pass device. They usually have some other magic for specific purposes but the core is still a 723. The TL431 is a great building block as well.
You can learn a lot from the Lambda manuals many of which are free on line around the web.
The supply circuit I linked doesn't use a follower. Its intentional for low noise. Using the pass device as an amplifier can get its noise lower that it would be as a follower.
I don't think starting from the junk box is a good way to solve a power supply task. Work back from what is really needed. Distributed supplies can work much better even if they are little more than cap multipliers. The isolation between stages if the stages have some power supply rejection can really improve things. I would never say supplys are not important but obsessing over nanovolt noise on a circuit with a 10K series resistor from the supply kind of wastes the efforts. Look at each stage and what it needs and work back. Maybe 8 10 cent transistors, two zeners with caps and two current diodes is all that is necessary if the the ripple isn't bad. Sometimes regulation really is not necessary, just filtering.
Biggest failing I see is not understanding the return current paths and getting the junk the regulator is supposed to remove added back in to the ground leg to the next stage.
Expanding a bit on Demian's suggestion, an approach yielding excellent results when you get it right is distributed local regulation.
The idea is to have powerful stabilizers (e.g. 317), which can easily feed the lot, as a starting point, They regulate to say +/- 30V or so. Each preamp block then has a local regulator reducing this to say +/- 24V, or whatever you need, using cap multipliers with a zener diode on their bases/gates.
The idea is to have powerful stabilizers (e.g. 317), which can easily feed the lot, as a starting point, They regulate to say +/- 30V or so. Each preamp block then has a local regulator reducing this to say +/- 24V, or whatever you need, using cap multipliers with a zener diode on their bases/gates.
There is not such thing as cap mult. with a zener diode on their bases. You have either cap multiplier(without zeners) with RC filter or series follower voltage regulator with zeners and series pass transistor which is worse than LM 317 ( more ripple and noise). It is better to use cap. multiplier here after LM-s.
My two kids are Autistic. Emeline has about 300 % better hearing as tested at the University nearby in Oxford ( something they are doing and I had no idea about the tests ). This was a liberation for me. To me Autism is an evolution which is shared by all humans. So Autism, blindness and deafness on a scale of 1 to 10 is everyone. One of the strangest Autistic traits is not understanding that the other person isn't fine tuned to a conversation because they haven't devoted their lives to study. This is because people bluff and like to keep up. I think in psychiatry it is called blue box pink box. Children up to maybe age 7 believe if they put something into a box other children or people entering a room will know exactly where it is. 50/50 chance but that is not the point. When the realization comes that secrets are possibly lying becomes second nature. Autistic people are week on this. If you like the idiots who understand is the Autistic trait. My son is now driving , a victory. I would never have thought it possible.
Living near Oxford I realize Autistic is most people here. It is odd to go to other places where the balance is different. A young Californian man I know said I would only truly be happy in California. I suspect the whole of Greece is Autistic and I love them for that. Women hide Autism better than most. Colleen certainly does. I can disarm her in seconds. The world we now live is is almost designed for Autistic people. Texting was a spare function for engineers to test the system. If texting isn't pseudo Autism I have no idea what is. Autism seems to be when you do your own thing regardless. Thin line I would say.
Having read many here and the DIY Audio forums many fit the mold. I think not having English as a first language helps as it forces people to use the other side of the brain. They get a double benefit. First the Autism dilutes and any residual is taken to be a translation error. I would say if not Autistic the very fact someone is here rather than doing something face to face is evidence of something. Myself I have something as yet unlabeled like Parkinsons. I think forcing myself to write for the first time in my life ( yes ) has been therapeutic. I now drive my car differently and I feel more fluidity. I am sure it is linked.
On interesting thing. English is a peculiar language. I seem to invert phrases as in old English especially when tired. Perhaps English is all affectation? I remember when at school the science of a piece of work 2 marks, all the other nonsense 8 marks. I notice most of the high flying kids I went to school with do very ordinary jobs. The worst of this story is I taught myself everything I know up to going to college. Then it was warp speed ahead. I would have stayed at college for ever.
How do you tell an Autistic person ? They start in mid sentence. Test your friends.
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Yes and no. Be very sure you test that concept.
In 1973 I was shown the amplified Zener. I was instantly told to forget it by the tutor as having passed into history.
Figure 2 is the Dvv Dejan idea I think?
Simple circuits reduce regulator noise floor | EDN
I am looking at LM723. Shame it can not do 1.5 A like LM317. LM 723 allows it's internal device like a zener to be filtered. Residual goes from 20 uV to 2.5 uV. Shame the one inside LM317 couldn't be " zener or band gap filtered " . Problems with zerers is tolerance and temperature effects. Often that isn't a problem. I use them in capacitance multipliers to define safe maximum.
Does anyone know the noise level of LM723 with NPN pass transistor. I want - 144 dB reference 12V. LM723 gets close. I am thinking of banking 15 together with 10 x 1 R combining resistors. I might by statistical noise cancelling gain more than the 1R looses.
I should have said. My friend needs a single 1 amp 12V of very low noise to replace a switch-mode. I have this very cheap train controller with LM 317 inside. I am tempted to start him on that. It was £7 as they were being upgraded in the store to SMPS! I bought two and it was such a good thing to do. For some reason they go to 24 V.
I got a little bee buzzing in my head saying 24 bit = -144.5 dB ( 24 x 20 x 0.30103 ). I know reality says this isn't important. Still would like to try. Tom Evans friend said they were getting that low. He said - 180 dB then corrected himself. That's the TAG test gear they can borrow.
I got a little bee buzzing in my head saying 24 bit = -144.5 dB ( 24 x 20 x 0.30103 ). I know reality says this isn't important. Still would like to try. Tom Evans friend said they were getting that low. He said - 180 dB then corrected himself. That's the TAG test gear they can borrow.
Very interesting use to do that in my youth ( Start thing in mid sentence ) . Have come to realize people are very slow to grasp concepts and you must start slowly and take them thru by the hand . I do tend to relate to other better when they share my knowledge base even thou they reach much different conclusions then I do about things. Texting does more than test autism in reinforces behavior that is anti-social without the clarity of vision I have found being effected by autism . It is the dumb and dumber version of social autism from my view.
I think Autism might be very common. It might just describe rather focused people. Trust me, women may have it more than men. Those cute things they do covered up by multitasking ability. Colleen always starts mid sentence. She always treats me as dumb that I am not up to speed. I challenged her recently and she knew she did it. She just giggled. She was intrigued and never once said impossible. When I first went out with her I said she was a changeling. She is also the most outwardly balanced and level person I know of. It's a front.
Mid sentence seems to be something that was in picture or story mode. It then seems important to say it.
I asked a friend if he learned from things he had written? He said all the time, sometimes what was said grew 9 fold in telling. I can not claim that. Strangest thing is when I write I am also one who reads it. I learn from what I just wrote. It's like baking a cake. In my case often half baked as I want to have someone put it back in the oven.
Mid sentence seems to be something that was in picture or story mode. It then seems important to say it.
I asked a friend if he learned from things he had written? He said all the time, sometimes what was said grew 9 fold in telling. I can not claim that. Strangest thing is when I write I am also one who reads it. I learn from what I just wrote. It's like baking a cake. In my case often half baked as I want to have someone put it back in the oven.
As Nigel pointed out, do look at the second schematic. That is the same as a cap multiplier, but with an added zener diode (ot two in series) to very precise voltages out.
You can also add yet another capacitor after the regulator, in which case you have what Technics called a "virtual battery". So, I typically use two 2,200 uF caps in parallel before the regulator, and a third 2,200 uF cap immediately after the regulator, in parallel with 220 nF.
The beauty of thet configuration is that the first 2,200 uF caps can be of regular quality, but the one after the regulator must be of better quality because this is the one which can affect the sound. "Better quality" means something like F & T, Siemens, Nichicon, etc.
I use this as a regulator for the input stages and VAS circuits, plus the predriver, all told using about 35-40 mA of current. And believe me, you will have to dive deep to find the noise floor.
When treating me for my Pseudo Parkinson's I was on some nasty drugs. It gave me a chance to run in a lower gear. I hated it, living death. I now take nothing and have a tremor. I can solder so where is the problem. Very grateful I got the chance to be the other person for nearly a year. The doctor thinks I might be lucky and this is how I will stay.
Anyone who is intelligent and motivated will show Autistic traits ( my observation ). Many school teachers do. I wonder sometimes if they have the worst job. So many things blocking them from the simple part of the job. Have you noticed many teachers never finish a sentence? I suspect it is because they are always expecting to be corrected ( PC ) and have lost contact with the reality of their childhood due to psychobabble. One was on the radio last night. 95% nonsense said until she said " I teach the values of Aristotle as it excludes no one". I could relate to that. If she had said only that it would have been excellent. Mostly she sounded like someone in full retreat, disguised hostility and incoherent. I am one to talk, I don't mold the minds of children so perhaps do no harm?
Anyone who is intelligent and motivated will show Autistic traits ( my observation ). Many school teachers do. I wonder sometimes if they have the worst job. So many things blocking them from the simple part of the job. Have you noticed many teachers never finish a sentence? I suspect it is because they are always expecting to be corrected ( PC ) and have lost contact with the reality of their childhood due to psychobabble. One was on the radio last night. 95% nonsense said until she said " I teach the values of Aristotle as it excludes no one". I could relate to that. If she had said only that it would have been excellent. Mostly she sounded like someone in full retreat, disguised hostility and incoherent. I am one to talk, I don't mold the minds of children so perhaps do no harm?
Mr Pearson, we'll have to start adressing you as 'you old gait'.
My experience is that most people do not Start, but End at half a sentence.
For some reason, when people have to write it down, they're able to be coherent.
I think the greatest gift one should give ones children is to think for one self and speak what they think when only they know that the listener is worthy. From personal experience tell some one their wrong and you being right is no way to move thru social interaction .
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