Hi Mark. Given a good match, the answer is yes and absolutely. This is answered in my second post.
Nigel, this is a whole list of utter truth, exactly what I am looking for! Thank you very much for understanding.
BTW, I am not looking for a job of strict board swapping. In my opinion, that job is basic manual labor with the occasional use of a DMM. I like skills whose foundation is in understanding. All new generations get to choose what they will keep and what to throw away from the generations prior. I like the speed and efficiency of the board swap, but I also like the aspect of serviceability. I believe a product that is designed to be serviceable requires the consideration of quality.
Massachusetts is petitioning Local Gov. to enact the Right to Repair. This bill would ensure access to replacement parts and schematics from the manufacturers who sell here. I don't know the whole scope of the bill yet.
Do you know how to read schematics? If so, to what extent have you learned how to deduce how a circuit works, say, a guitar amp from looking at the schematic?
If you do happen to know how to read them and figure out a few things, it will help us to understand approximately where you are trying to start from at this point. If you don't know anything about it, that could be an honest answer too.
If you do happen to know how to read them and figure out a few things, it will help us to understand approximately where you are trying to start from at this point. If you don't know anything about it, that could be an honest answer too.
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The Valve Wizard
Although the world is now class D no harm doing a little reading. Here is the source I trust along with ex BBC Morgan Jones. MJ is the missing link. A man who see the scientific qualities of valves and uses transistors to get more from them.
Valve Amplifiers: Amazon.co.uk: Morgan Jones: 9780750656948: Books
Soil science is good. My dad did that and also electronics. He seems to talk almost as if they were the same. I am doing the periodic tables right now, my boss wanted something that needed it. The tables have the feel of an unfinished project. Whilst there are trends I wouldn't call it completely obvious. For example why is silver only only slightly more conductive than copper and gold worse than either, the deeper you go with that the more unfinished it is. I came up with a concept of the conductivity per unit mass, non seem interested in that. When asked that way copper is the better one and aluminium better still, aluminium is hard to analyse, some saw it as a metaloid. My guess is my dad planted those seeds when talking soil chemistry. I remember at age 4 him using a litmus test for our soil. Even then I knew my dad was not Mr Average. Apart from science he never spoke. He taughts me thermionic valves when I was 4. It wasn't difficult. He is 87 now and still has his head in a book.
My sucess came when my mother saw an advert for a place I had always liked. Work was hard to come by. I was asked at the interview was I good at repairs. I really didn't know, but obviously said the right things. As soon as I entered the place it was Heaven on Earth. My boss's real idea of a repair was sending it to whoever made it. In short time I didn't do that. Even though a bit less artistic than some I always tried to make things look as good as new when repaired. That ability has gone now, now I am just happy to fix it. One thing I learnt was to phone the peole who make it and say " before I send it to you what should I check ". I remember my pride when I was told we were unique in how little that came back. My boss would have been happy if I had been just able to process the repairs. Apparently he didn't like the fact I knew more than him. He was a design engineer for Smiths when clocks and things in aircraft. He had this illussion that being an engineer with a keen interest in electronics made him a PHD.
After I had repaired many things I started to ask why one sounded good and another not. I am still asking this. I do find like the periodic tables that is not a complete science. Do you know I really know this stuff and no one at DIY Audio is really interested. Gradually I learnt why should they. It's their discovery and let them do it. If asked what I would say make it as simple as you can and still have a remarkable specification. Your power supplies will matter. Like the Periodic Tables that isn't a complete science. The reason being people never measure things carefully enough if they do at all. Their Soil Science lets them down.
It's all luck really and you have to have a lot of self belief.
Although the world is now class D no harm doing a little reading. Here is the source I trust along with ex BBC Morgan Jones. MJ is the missing link. A man who see the scientific qualities of valves and uses transistors to get more from them.
Valve Amplifiers: Amazon.co.uk: Morgan Jones: 9780750656948: Books
Soil science is good. My dad did that and also electronics. He seems to talk almost as if they were the same. I am doing the periodic tables right now, my boss wanted something that needed it. The tables have the feel of an unfinished project. Whilst there are trends I wouldn't call it completely obvious. For example why is silver only only slightly more conductive than copper and gold worse than either, the deeper you go with that the more unfinished it is. I came up with a concept of the conductivity per unit mass, non seem interested in that. When asked that way copper is the better one and aluminium better still, aluminium is hard to analyse, some saw it as a metaloid. My guess is my dad planted those seeds when talking soil chemistry. I remember at age 4 him using a litmus test for our soil. Even then I knew my dad was not Mr Average. Apart from science he never spoke. He taughts me thermionic valves when I was 4. It wasn't difficult. He is 87 now and still has his head in a book.
My sucess came when my mother saw an advert for a place I had always liked. Work was hard to come by. I was asked at the interview was I good at repairs. I really didn't know, but obviously said the right things. As soon as I entered the place it was Heaven on Earth. My boss's real idea of a repair was sending it to whoever made it. In short time I didn't do that. Even though a bit less artistic than some I always tried to make things look as good as new when repaired. That ability has gone now, now I am just happy to fix it. One thing I learnt was to phone the peole who make it and say " before I send it to you what should I check ". I remember my pride when I was told we were unique in how little that came back. My boss would have been happy if I had been just able to process the repairs. Apparently he didn't like the fact I knew more than him. He was a design engineer for Smiths when clocks and things in aircraft. He had this illussion that being an engineer with a keen interest in electronics made him a PHD.
After I had repaired many things I started to ask why one sounded good and another not. I am still asking this. I do find like the periodic tables that is not a complete science. Do you know I really know this stuff and no one at DIY Audio is really interested. Gradually I learnt why should they. It's their discovery and let them do it. If asked what I would say make it as simple as you can and still have a remarkable specification. Your power supplies will matter. Like the Periodic Tables that isn't a complete science. The reason being people never measure things carefully enough if they do at all. Their Soil Science lets them down.
It's all luck really and you have to have a lot of self belief.
The periodic table dates back to around 1869, a time when almost nothing was known about atoms - we didn't know about electrons, protons, or neutrons yet, never mind all the other subatomic particles. So there was very little science involved at first.
Even before that, in 1863, John Newlands grouped the elements (only 56 were known back then) by their chemical and physical characteristics. He came up with 11 groups of elements. Within each group, there were similarities in properties. This was only an observation - hardly a science. Kinda like collecting all your round beads into one basket, elliptical beads into a second, cubical beads into a third, and so on.
1n 1869, the periodic table started out as another attempt to organize beads (elements). The concept of atomic mass was already known, and Dimitri Mendeleev started to arrange the known elements in increasing order of mass. Like Newlands before him, Mendeleev found that their chemical properties tended to fall into clusters.
But because Mendeleev was arranging his elements in order of increasing atomic mass, every now and then, he could tell that there was a missing element because of the jump in atomic mass, and the way the properties of the elements changed from one group to the next.
There was still no hard science to speak of at this point - just a few useful general observations about elements. Kinda like noticing that there were small house cats, and big lions, and they had some shared properties (such as being entirely carnivorous), and then wondering if maybe there were other types of cats in sizes between house-cat and lion.
Mendeleev's guesses did lead people to find bigger and smaller cats. Missing elements were found, one by one.
Nearly 30 years later, the electron was discovered. Then, a few more years later, the proton. Then the neutron.
Fast forward some more, and starting in the 1920s, the field of quantum mechanics was developed. Schrodinger's equation was a huge breakthrough. So was the discovery of spins (subatomic particles have a property called spin.)
Finally, we had a science that could really tell you what those pesky little atoms were doing - and how and why an element would behave.
So yes, the periodic table is a crude and incomplete project, because it dates from a hundred and fifty years ago, a time at which we knew a lot less about the physics of very small things (atoms, etc). It's like a map of the earth from the 1500s - we wouldn't expect that to be very scientifically useful today, either!
But for the last seventy or so years, the science of how elements behave is no longer an unfinished project - the answers can all be calculated using quantum mechanics. The calculations are cumbersome, and scientists had to wait until fast computers arrived to deal with the bigger and more complicated atoms, but there is no missing knowledge there any more.
Today, I doubt scientists look in the periodic table for clues to new discoveries. That would be like looking at a map of the world from the 1500s in the hope of finding new continents.
-Gnobuddy
I hope the gentleman who asked the question won't mind what is typical of education in the round here. Element No 43 is really interesting as it looks to belong with No 93. Please tell us off as we deserve it for this. I told my boss that I see electronics as a black and white world and chemistry as colour. Then I thought about it. Electronics likes it that way. My boss wanted to know why silver is more conductive than copper. Looked at from another point of view it isn't. That is per unit mass. Aluminium is good then. I was also surprised sodium wasn't better. Per unit mass it is. Gold is less good regardless of how ones looks at it which is slightly bonkers as it meets most of the rules than look to be important. As far as I know no one says this.
Using reinforced aluminium for electrical cables not only is cheaper it also withstands wind better. There are many problems when using aluminium, electrical resistance isn't really one of them. As far as I know Aluminum was an error in a text that persisted. I shall be doing aluminium in a mechanical engineering context soon. For this I want it to be moderately impure.
I told my boss, it's not why is silver so good, it's why is copper as good as it is. Here are some factoids. If copper is 99.6% pure I would think it to be 99% as good electrically as it could be if a standard refined product ( ETP minimum grade ). If 0.04% phosphorous is the impurity it drops down to 85% conductivity as a form of bearing copper or tram electrical contact at 800 VDC typical. 99% copper brass is about the same. Thus 0.04% phosphorous is as harmfull as 1% zinc. Silver is less harmful. Silver can be 16% to do the same. Sometimes the trade off is worth it. Tellurium copper is a very nice compromise at about 93% conductivity, sulphur being similar to tellurium and can be used, it is a useful alloy.
The scientists solving the tables called things Rare Earth. They are not really earths and they are not rare. Soil science at it's best? Alchemy is wonderful and still possible. Element 43 proves this. It is seen in star spectra. I suspect the star modifies molybdenum that glances it. A normal star would not be able to make it internally as far as I know. Chalk that up to me if it ever becomes fact. It is a mystery as it can not be true. The world of chemistry allows for that. When you listen to music it also has mysteries that the science of hi fi seems not to notice.
Using reinforced aluminium for electrical cables not only is cheaper it also withstands wind better. There are many problems when using aluminium, electrical resistance isn't really one of them. As far as I know Aluminum was an error in a text that persisted. I shall be doing aluminium in a mechanical engineering context soon. For this I want it to be moderately impure.
I told my boss, it's not why is silver so good, it's why is copper as good as it is. Here are some factoids. If copper is 99.6% pure I would think it to be 99% as good electrically as it could be if a standard refined product ( ETP minimum grade ). If 0.04% phosphorous is the impurity it drops down to 85% conductivity as a form of bearing copper or tram electrical contact at 800 VDC typical. 99% copper brass is about the same. Thus 0.04% phosphorous is as harmfull as 1% zinc. Silver is less harmful. Silver can be 16% to do the same. Sometimes the trade off is worth it. Tellurium copper is a very nice compromise at about 93% conductivity, sulphur being similar to tellurium and can be used, it is a useful alloy.
The scientists solving the tables called things Rare Earth. They are not really earths and they are not rare. Soil science at it's best? Alchemy is wonderful and still possible. Element 43 proves this. It is seen in star spectra. I suspect the star modifies molybdenum that glances it. A normal star would not be able to make it internally as far as I know. Chalk that up to me if it ever becomes fact. It is a mystery as it can not be true. The world of chemistry allows for that. When you listen to music it also has mysteries that the science of hi fi seems not to notice.
This thread baffles me. OP states advanced math and electronics training but spent 100 hours tracking down 120Hz hum after replacing an interstage transformer with active components? It would have taken less time to rewind the transformer yourself, or even easier just find a suitable replacement. I don't repair guitars but someone I restore amps for had and old Kay bass guitar where the zippo pickup was dead. Good luck finding a replacement that will fit. I ordered some 43 awg magnet wire, made a winding jig in an hour and about 5 thousand turns later the thing sounded amazing. Sometimes you just got to get it done alone.
I am not judging but you can learn a lot by just reading books and asking the right questions over the interwebs. These days you don't need one mentor, you have the whole world as mentors over a wire. Start a thread on a specific topic you are having trouble with like tracking down hum, or oscillations. People will chime in with their own experiences and learn from multiple people not just one person.
A few books, some basic tools, and this forum has taught me so much over the years it's practically priceless. If I could buy everyone that helped me a beer and lunch I would but honestly there are so many nice people on here willing to help all they do it for is gratitude. Then once you learn come back and help others.
I am not judging but you can learn a lot by just reading books and asking the right questions over the interwebs. These days you don't need one mentor, you have the whole world as mentors over a wire. Start a thread on a specific topic you are having trouble with like tracking down hum, or oscillations. People will chime in with their own experiences and learn from multiple people not just one person.
A few books, some basic tools, and this forum has taught me so much over the years it's practically priceless. If I could buy everyone that helped me a beer and lunch I would but honestly there are so many nice people on here willing to help all they do it for is gratitude. Then once you learn come back and help others.
I think most emotionally healthy people enjoy sharing and helping each other - we are a species that lives in herds, our ancestors would not have survived long if isolated from the family group. If nobody in the pack keeps watch at night, the hyena will eat your face off your skull in your sleep.
And if you don't find any food in your hunting today, maybe your sister or uncle or friend did - your life depends on their sharing it with you. Tomorrow you might return the favour.
So, for the most part, evolution has wired our brains to behave in ways that keep the herd together. That includes wanting to help when we can without too much cost to ourselves. Helping other people makes us feel happy (well known to psychologists and brain researchers these days.)
Of course there are also abnormal people. We all know some people who are selfish, who like to hoard their knowledge rather than share it, or worse, will try to steal your stuff (maybe even kill you first.)
That's evolution for you, it has no morality, it blindly finds every path that leads to survival. If one person out of every ten is greedy, he/she might do well for himself/herself. But if ten out of ten are greedy, all would have died during our harsh early history.
-Gnobuddy
When we share we all get more. The trick is knowing what the thing we trade is worth. Look at a nurse and a doctor. In the UK a nurse is paid below a level where they can buy a house. A doctor often has enough spare money to have a few houses. When a junior doctor often the nurse knows more. These days a nurse has a degree, our Police will soon. When a social worker I would allow some doubt over the degree they have compard with a science BSc. Not so a nurse.
On our Open University a maths transmission looked at the teachings of our state religion without the religion. That is to say what is the result of truely sharing. They found we all would be considerably richer if we took that route. Their conclussion was people get great enjoyment out of seeing themselves better than others even if everyone suffers as a result. Their main conclussion was it was obvious if given a chance. Sweden and Norway look a bit like they understand maths better. If you look at Sweden not so long ago it was a very poor country. I can only guess they took the best ideas of their neighbours and kept it very simple. Look at the great science that came from Sweden.
On our Open University a maths transmission looked at the teachings of our state religion without the religion. That is to say what is the result of truely sharing. They found we all would be considerably richer if we took that route. Their conclussion was people get great enjoyment out of seeing themselves better than others even if everyone suffers as a result. Their main conclussion was it was obvious if given a chance. Sweden and Norway look a bit like they understand maths better. If you look at Sweden not so long ago it was a very poor country. I can only guess they took the best ideas of their neighbours and kept it very simple. Look at the great science that came from Sweden.
10 minutes of excellent guidance or "focusing" can save 100hrs. That is the purpose of the post - find a guide. To clarify, I was hunting down a hum that was too loud to be acceptable for any guitar amp or Williamson/hifi, without knowing that the gears and XF's found inside the jukebox would put the amps hum to shame! That perspective was outside of my view. This was the first project that I accepted without receiving the entire chassis/component base.
Interstage XF winding is not as common as it used to be. After learning that, through prospective contacting of several XF winding companies, I decided I would build a preamp card, learn and fix the amp at the same time.
*This post is not a matter of finding a technical Tudor quite as much as it is about finding a guide, someone who has already walked this path and knows the pitfalls and opportunities. Google and Youtube are free, but they are not reasoning machines.
I stand clear and reaffirm my intentions. I will find someone who enjoys the satisfaction in steering me clear of "rabbit-holes" for the low, low price of (1) 10min phone call per week. Money management, Time management, correct analysis/solution, business strategy, these are all possible subjects as well as the discussion of anything specific to electronics. Thank You.
I am 62 now. I still fall down rabbit holes. I think like many my peak was around 43.
You could take a big risk and set up as a repair person. No fix no fee. That's how I did it. Looking back I knew nothing. I had surprisingly few failiures. OK I had the theory, in reality it was only 20% of the job. What you say when it's obvious the job is not easy is " sorry, it's not obvious, no fee ", people will like that. My rule is if I don't have a good idea of the fault in 20 minutes I should give up, if only I followed that rule, I try. The thing you must learn is leave it alone if even slightly unsure. Have the right screwdrivers and a black marker to make black screws look like new when done up. An impact driver used as screwdriver is good. The weight seems to help. Have a desoldering tool and solder wick. I use a small 15 watt iron and 25 watt one. If the job is tough I use both. A bright light is vital. Take photo's as you go. A small gas iron is useful.
Even when I built body scanners no one taught me. It was very like other things I knew. At first I didn't have a clue. In two weeks I was getting on top of it. I learnt a little by asking. Mostly it was reading spec sheets. When I left I was asked to help solve a problem that beat the rest of them. An experimental coil was 2" out of focus. It was an asymetrical coil which was not common. The coil unlike any we made had no former at the end. I said the former is usually 2" that must be the problem, wound from the wrong point. I remember thinking how come they didn't see that. Easy, my hands got dirty and theirs didn't. It was a very noisy place, I left to save my ears. Sometimes I worked alone on a Sunday when a contract was due. It was pure bliss. Myself and the security guy where often 100+ worked. That was often using a 3000 watt Crown amplifier to test the magnetic field of the coils in X,Y,Z using a magntometer. If any metal object moved in the building I could not work. The really cute thing was the outer coils were conected in antiphase to get the field required. The test was to get the inductance lower than the primary coil showing that the phase was correct. The magnetic centre had to be correct. Imagine doing that and no one really willing to train you. Worst part was the very untidy look of the job. Coil ends were like a thick flat pencil. The enamel took ages to get off with a file. The coil ends were wire wrapped in antiphase and soldered, often it took a few attempts to get it right. It worked, I hated that. It was encased so no one saw it. The coil might be 8 foot tall and nearly always held a nasty high charge on the open coils. I seem to remember the charge was a test in itself although not how the device worked.
I watched a TV show about Cuban cars and how they fix them. That's how learning should be. It will be rare these days. My son fixes computers. What that means is he puts new cards in. Mostly that's what you will learn. A university lab might be good.
You could take a big risk and set up as a repair person. No fix no fee. That's how I did it. Looking back I knew nothing. I had surprisingly few failiures. OK I had the theory, in reality it was only 20% of the job. What you say when it's obvious the job is not easy is " sorry, it's not obvious, no fee ", people will like that. My rule is if I don't have a good idea of the fault in 20 minutes I should give up, if only I followed that rule, I try. The thing you must learn is leave it alone if even slightly unsure. Have the right screwdrivers and a black marker to make black screws look like new when done up. An impact driver used as screwdriver is good. The weight seems to help. Have a desoldering tool and solder wick. I use a small 15 watt iron and 25 watt one. If the job is tough I use both. A bright light is vital. Take photo's as you go. A small gas iron is useful.
Even when I built body scanners no one taught me. It was very like other things I knew. At first I didn't have a clue. In two weeks I was getting on top of it. I learnt a little by asking. Mostly it was reading spec sheets. When I left I was asked to help solve a problem that beat the rest of them. An experimental coil was 2" out of focus. It was an asymetrical coil which was not common. The coil unlike any we made had no former at the end. I said the former is usually 2" that must be the problem, wound from the wrong point. I remember thinking how come they didn't see that. Easy, my hands got dirty and theirs didn't. It was a very noisy place, I left to save my ears. Sometimes I worked alone on a Sunday when a contract was due. It was pure bliss. Myself and the security guy where often 100+ worked. That was often using a 3000 watt Crown amplifier to test the magnetic field of the coils in X,Y,Z using a magntometer. If any metal object moved in the building I could not work. The really cute thing was the outer coils were conected in antiphase to get the field required. The test was to get the inductance lower than the primary coil showing that the phase was correct. The magnetic centre had to be correct. Imagine doing that and no one really willing to train you. Worst part was the very untidy look of the job. Coil ends were like a thick flat pencil. The enamel took ages to get off with a file. The coil ends were wire wrapped in antiphase and soldered, often it took a few attempts to get it right. It worked, I hated that. It was encased so no one saw it. The coil might be 8 foot tall and nearly always held a nasty high charge on the open coils. I seem to remember the charge was a test in itself although not how the device worked.
I watched a TV show about Cuban cars and how they fix them. That's how learning should be. It will be rare these days. My son fixes computers. What that means is he puts new cards in. Mostly that's what you will learn. A university lab might be good.
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