1.0uf replacment capacitors?

[DAVEHALL]

Originally Posted by Station X

In many cases we're using components of similar value in order to get half the value or twice the value. That's exactly what post #1 is proposing, but we've been side tracked into a lot of what I consider to be over complicted mathematics.

But in electronics- it's not overcomplicated maths ,just the application of science (and maths,to solve the problem) .How else did the original circuit designers arrive at the set values - by what is said to be "complicated maths" .
Now ,I'm not taking P ,but to be seriously interested in the subject ,one has to get involved in how components values are arrived at -and that needs some maths .That way , an understanding of electronics and the theory starts to help .My education in electronics /radio etc, as a maintenance /faulting engineer was
1) - Learn how it works
2) Find out what it's not doing .
3) - 1-2 = what's wrong , and sometimes deciding on where in the circuit the fault lies may require some maths - usually a simple application of Ohms Law .

[Station X]

I'm not intimidated by mathematics, but for me it's sufficient just to know the basic expression for series/parallel combinations rather than being able to derive the expressions as described in post 7. That sort of thing drives newbies away in their droves.

I can derive expressions and prove formulae if need be, but I've only needed to do so in order to pass exams.

[wireful3]

I would like to add to Grahams post.

For our hobby it is not essential to be able to derive these expressions. It is enough to know that someone has done it. The expressions themselves though can be very useful, and even more if they can be manipulated a bit.

I have often found that the resistors in parallel or capacitors in series formula has been handy when I don't have the exact value component but something near but too big.. Rearranging the basic formula makes it easy to find the capacitor value to put in series to get what I need. There are now calculators on the internet that do this for me so life is getting simpler.

It is the same for resistors in series and capacitors in parallel but here the rearrangement is more obvious.

The formula also gave me an understanding of how bandspread on SW worked. It was not really relevant to restorations I have been doing but had often wondered how the very large tuning capacitor could be arranged to cover such a small frequency range as a single SW broadcast band. I have never been very keen on mathematics and have not worked on radio design or even repairing them but it gave me a simple pleasure to see that mathematics could help me understand something that had been a puzzle.

[geofy]

Without trying to drift OT I think most people are put off maths because of the poor way it is often taught in schools, if my experiences where anything to go by, I would be left foundering because I couldn't understand why a simple move was made, say like taking and expression over and it becoming a minus or a times became a divide. And I would sit though the entire lesson stuck at this point with the teacher just concentrating on the one or two 'star' pupils who did understand it.

I recently looked at a question on series and parallel resistor circuits that my sixteen year old niece in Australia had to solve. And it was poorly scribbled out and the teacher didn't explain why resistors had to be worked out like this or EVEN what a resistor was, hardly likely to foster a liking for the subject of electronics. I helped her to sort out the circuits in a better way and she got better grades during the exam she had to take afterwards because of my explanations.

But maths is in everything, the entire universe.

Geof

[AndiiT]

Originally Posted by Station X

I guess we all do what comes easiest to us

Some years ago a freind, whilst referring to baking/cooking, told me "Always stick to the method that you know works" this can also be applied to Mathematics, or indeed many other aspects of life.

I personally favour the "Product over Sum" method for components in parrallel, not being a fan of these new fangled calculator thingies , but tend to only use this when the components have differing values.

Originally Posted by Station X

In many cases we're using components of similar value in order to get half the value or twice the value. That's exactly what post #1 is proposing, but we've been side tracked into a lot of what I consider to be over complicted mathematics.

I agree about being side tracked in to over complicated maths, but nevertheless interesting to some and good for brushing up on the theory

Regards
Andrew

[thermionic]

Originally Posted by Station X

I guess we all do what comes easiest to us

Exactly! My ability of understanding maths could be likened to a goldfish swimming in a bowl of treacle.

I remember this 'product over sum' method by referring to it as the 'MAD method'

M= multiply

A= add

D= divide

...can't go wrong!

SimonT.

[DAVEHALL]

Originally Posted by Station X

I'm not intimidated by mathematics, but for me it's sufficient just to know the basic expression for series/parallel combinations rather than being able to derive the expressions as described in post 7. That sort of thing drives newbies away in their droves.

I can derive expressions and prove formulae if need be, but I've only needed to do so in order to pass exams.

Post 7 was mine - and not intended to drive anyone away - just make them look at things differently -and offer a different POV .Throughout my Professional career as a telecomms engineer , I had trainers trying to get me to look at circuits and evaluate what the meter told me - and work out ( using OHMS Law) if things were right - looking at circuit paths to see if the right currents were flowing -etc . The meter can give you a reading - maths can help you decide if it's true or false .That's when an engineer comes into his own -and something I'd like newbies to latch on to .