I'm a novice tinkerer in electronics.
its a hobby that takes alot of google'n and patience getting nowhere sometimes,but a lot of satisfaction when you build a board that works well and can be used and not just create more crap to put in the top drawer.
For instance in building a infra red security cam that's the size of a 50p coin excluding the power supply.
At school I started with building Sinclair radios and selling them to class mates until the teacher got wise to why there were so many hearing aids. This was back in mid 1960's when the new MAT transistor was used by Sinclair before he got into making computers.
AVO Multi-minor was may main test tool and as I got a little older girls became my new hobby.
I returned in around mid 1970's when the firm I worked for go new electronic traffic lights which I was taught to repair so had a cheap supply of TTL chips I could use. Many failures made a great windscreen wiper pause controller until the engine was turned on then it went crazy.
Mid 1980's working in the Falklands again started a renewed interest with loads a amateur radios being used as walkie talkies and I did some of the minor repaired to them and got a Falklands licence (VP8BKM).
On return to UK I did a course and exam and got my UK licence (GW7MGW) and again did some minor repairs on PMR radios. My son also passed his exam and I got into packet radio building my own modem (Baycom) this continued when I moved to Hong Kong where I got another licence VR2ZEP but on return did not really have the opportunity to erect aerials so the hobby died out.
However after an accident and going to college to study IT when it came to going to University I decided I didn't like IT so did degree in Electrical and Electronic engineering.
I have renewed my interest in Amateur radio and am now an active member of RAYNET and was until this year chairman of local radio club. I don't have aerials on the side of my house all hand held stuff.
I was useless programming PIC's but good with programming PLC's I designed and built all the control for a concrete press making washing machine weights one every 25 seconds.
The amateur radio has been main source of help. There are so many playing with electronics at all stages and I would recommend trying out a few clubs. There are clubs who do not get into self build and others are way beyond my level so you may need to try a few.
The entrance has changed since my day no longer a RAE exam but stages so it's a hands on entrance not just theory as before. And Morse has gone from the exams.
I do very little building now my hobbies have moved to Photography but I will return I am sure.
Yes the old Tony Hancock days have gone. There are still some who try something special like earth moon earth bouncing signals off the moon and even seen bounced off aircraft although it took them some time to realise that was what was going on but as a cheap method of chatting around the world it is no longer an option.
Be it my camera or radio to be asked to take a photo of that to show X or to get a signal from A to B where there is no cell phone coverage is a challenge and I enjoy that.
To order my spotted dick from Birmingham (Tony Hancock) is now pointless and I think that's why packet radio has all but gone.
However most radio hams don't only talk on radio but build things and it's that bit of the hobby which means joining the right radio club will help people with electronics as a hobby. One guy in our club is into mechanical watches and built an electronic machine to assist him setting them to keep correct time without having to wait for hours to see if losing or gaining time.
Most start by building simple power supply again not really special to radio.
Swapping ideas over a pint is to me a nice way to go about it.
I must admit beer at club meetings is double edged it does make for a more amiable atmosphere but also increases the cost.
The sorry I'm driving does work however and today no one is worried if you don't drink.
However I must admit when I was studying for my RAE I was happy that I was learning more and more about electronics but once passed I felt OK now what how do I take it further.
It took over 20 years before I found myself unemployed and able to take a degree in electronic and electrical engineering.
However it was the maths that was a problem if one has ever tried to calculate the size of heat sink then one would realise the problem. We got told it was easy as we didn't have to include time.
We were told by our Russian lecturer of how hard it was when time was included and he had to work out how long a power supply would run before it failed and was told when he worked out 2 hours before it failed that was OK as only took 1/2 hour to get rocket to USA.
Odd as it may seem some on the course found calculus easy but not me however I found imaginary number easy and they did not.
As a hobby we rarely have to delve into the maths I spent many hours working out the gain on op-amps for my home work and I can't remember any of the calculations now.
About the only benefit is I understand why Pi told i to get real!
In the old days we looked at the gain with a valve and how to set up the grid bias today with op-amps it is far easier. But even the 555 timer takes some understanding without the internet I would be lost.
However so many of the components shown are not really required and I really am glad I started in the days of the MAT transistor as to start today would be rather daunting.
Im going to take your advise and look into joining a few clubs, as i find i have stages of being right into it then long areas of nothingness!!!
I just never know where to kick off?
What to learn first? Because there is so much to learn thats interesting and alot thats bloody boring also!
One aspect i love doing is fault finding boards and components, What makes things tick. Then the satisfying bit.....Fixing the electronics.
But because im a novice i get frustrated because i get conflicting results when testing component on pcb's . which costs me hours of wasted time getting wrong results, and not learning much from it either.
I suppose its hard having the discipline when im working alone. Typically im not starting from page 1, im jumping to chapter 10...if you know what i mean? So im learning the juicy bits but not touching the fundamentals.
I do see the problem. So easy to correct some ones errors without showing them where they went wrong and its knowing what one did wrong that is important.
I found the humble power supply was a good starting point. There are many ways but it's the how which is important and I started simple.
So starting with standard battery charger which has a transformer and a rectifier and making it into a power supply.
Step one is smoothing the DC with a capacitor then you want to chop off the peaks, a 7812 IC will do all that but gives 12 volt and you want 13.2 volt so adding a red LED to common leg of 7812 gives one that extra 1.2 volt and gives a supply on indicator at same time.
Slowly one progresses. The problem with a battery charger is the voltage a a little too low so come the next model which sinks excess into a bulb rather than clip it off and so slowly we progress.
So lets present a real problem. Solar panels want to charge the battery as quickly as they can when sun is shinning and one can buy a cheap controller to do that but voltage sensitive equipment does not like pulse charging or bulk charging the latter can raise the battery to 14.8 volts. Also with three stage charging the current is what latches the controller into the final stage.
So challenge using existing controller if you want how do you.
A) reduce voltage to equipment when battery voltage at 14.8
B) compensate for current draw and drop battery voltage to 13.8 once 90% charged when also drawing current for say a TV which would normally stop the charger switching from bulk to float.
I have ideas but not a real working prototype so will say nothing more until some one takes up the challenge or suggests a different one.
If we pool ideas maybe that will lead us all into improving our skills? Not after circuit diagram just idea as to how to do it with cost a major factor.
At last found my copy of Electronics Workbench so can start again. For those who have never seen it I will explain. It is a computer program that lets you simulate what a circuit will do. My memory is not what it was and trying to remember which input to use for a op-amp is hard. [GALLERY=media, 73019][/GALLERY] to be able to simulate programs like this saves a lot of time and blown components. There are different stages the picture shows using virtual components which shows general principles but you can also select actual components like a 741 op-amp and transferring to Ultiboard even allows the design of a printed circuit to take the components.
Be it a complex digital system which without Mulisim would require Karnaugh mapping which is quite complex or a simple two way lighting circuit programs of this type really make it easy.
It was an essential tool when doing my degree in electrical and electronic engineering but when my desk top failed and I moved to a lap top I could not find the disc.
If you look at my pictures in DIYnot you will find many produced in Miltisim 7 so I am sure what I have shown does work as expected. The picture shown here is the odd one out I am still experimenting as to values and design aim is to finally produce a design for a stage battery charger.
OK one can buy a switch mode battery charger using pulse charging from Lidi at less than I can buy components to build the stage battery charger but it's down to the fun of building.
