Sunday fun

On this lovely Sunday I will be taking a trip to the seaside with the family which will be fun once I get back I will get back in the shed and do some more I hope to get somethings sorted maybe just clean up and do some Breadboarding. I'm working on some tool related things so hopefully they will be up tomorrow or Tuesday .

also there will be an update on the python in the coming week and a few other things over the next week.

Dobby

Photoresistor

A photoresistor (or light-dependent resistor, LDR, or photoconductivecell) is a light-controlled variable resistor. The resistance of a photoresistor decreases with increasing incident light intensity; in other words, it exhibits photoconductivity. A photoresistor can be applied in light-sensitive detector circuits, and light- and dark-activated switching circuits.
A photoresistor is made of a high resistance semiconductor. In the dark, a photoresistor can have a resistance as high as several megohms (MΩ), while in the light, a photoresistor can have a resistance as low as a few hundred ohms. If incident light on a photoresistor exceeds a certain frequency, photons absorbed by the semiconductor give bound electrons enough energy to jump into the conduction band. The resulting free electrons (and their hole partners) conduct electricity, thereby lowering resistance. The resistance range and sensitivity of a photoresistor can substantially differ among dissimilar devices. Moreover, unique photoresistors may react substantially differently to photons within certain wavelength bands.
A photoelectric device can be either intrinsic or extrinsic. An intrinsic semiconductor has its own charge carriers and is not an efficient semiconductor, for example, silicon. In intrinsic devices the only available electrons are in the valence band, and hence the photon must have enough energy to excite the electron across the entire bandgap. Extrinsic devices have impurities, also called dopants, added whose ground state energy is closer to the conduction band; since the electrons do not have as far to jump, lower energy photons (that is, longer wavelengths and lower frequencies) are sufficient to trigger the device. If a sample of silicon has some of its atoms replaced by phosphorus atoms (impurities), there will be extra electrons available for conduction. This is an example of an extrinsic semiconductor.

Photoresistors come in many types. Inexpensive cadmium sulphide cells can be found in many consumer items such as camera light meters, clock radios, alarm devices (as the detector for a light beam), nightlights, outdoor clocks, solar street lamps and solar road studs, etc.
Photoresistors can be placed in streetlights to control when the light is on. Ambient light falling on the photoresistor causes the streetlight to turn off. Thus energy is saved by ensuring the light is only on during hours of darkness.
They are also used in some dynamic compressors together with a small incandescent or neon lamp, or light-emitting diode to control gain reduction. A common usage of this application can be found in many guitar amplifiers that incorporate an on board tremolo effect, as the oscillating light patterns control the level of signal running through the amp circuit.
The use of CdS and CdSe photoresistors is severely restricted in Europe due to the RoHS ban on cadmium.
Lead sulphide (PbS) and indium antimonide (InSb) LDRs (light-dependent resistors) are used for the mid-infrared spectral region. Ge:Cu photoconductors are among the best far-infrared detectors available, and are used for infrared astronomy and infrared spectroscopy.
CH₃NH₃(Mn:Pb)I₃ a magnetic photoresistor developed in 2016

Quick update after a busy day

To day has been really busy and fun I've got a lot done I received a lot of great items in the post and made a start on the fume remover it was only the back plate but it was a start.

In other news I will starting to help out a local museum next Saturday which I'm really looking forward too.

Dobby 

Weekend Project

My main weekend project will be to build an Airfix Jaguar E-TYPE model then add some leds to give it working lights.

the leds will only be a small change but I think it will be a good one also I need to decide what colour to paint it I have been thinking Red , Black or Blue but I am open to suggestions

in other I got two ULN2803APG chips in the post today and I will be playing with them over the weekend .

Dobby

Ohm's law

Ohm's law states that the current through a conductor between two points is directly proportional to the voltage across the two points. Introducing the constant of proportionality, the resistance,^[one arrives at the usual mathematical equation that describes this relationship:

${\displaystyle I={\frac {V}{R}},}$

where I is the current through the conductor in units of amperes, V is the voltage measured across the conductor in units of volts, and R is the resistance of the conductor in units of ohms. More specifically, Ohm's law states that the R in this relation is constant, independent of the current.
The law was named after the German physicist Georg Ohm, who, in a treatise published in 1827, described measurements of applied voltage and current through simple electrical circuits containing various lengths of wire. He presented a slightly more complex equation than the one above (see History section below) to explain his experimental results. The above equation is the modern form of Ohm's law.
In physics, the term Ohm's law is also used to refer to various generalizations of the law originally formulated by Ohm. The simplest example of this is:

${\displaystyle \mathbf {J} =\sigma \mathbf {E} ,}$

where J is the current density at a given location in a resistive material, E is the electric field at that location, and σ (sigma) is a material-dependent parameter called the conductivity. This reformulation of Ohm's law is due to Gustav Kirchhoff.

useful link Ohms Law Calculator

V = I x R  (Voltage = Current multiplied by Resistance)

R = V / I  (Resistance = Voltage divided by Current)

 I = V / R  (Current = Voltage Divided by Resistance)

Dobby

Looking foward to the weekend

With the birthday out the way its time to look forward to another long week hopefully the parts in waiting for will turn up so I can get on with the projects I have planned out but even if they don't I have a small idea that I will do instead so at least I have to share.

In other news

I'm looking into posting one video a week possibly on a Saturday  and I am just looking for a good video editing software does anyone reading this have any suggestions ?





Dobby

Birthday update

Just a quick update today as its my birthday I will be spending time with my friends and family . I'm hoping that I can find some time to get in the shed and do some electronics stuff I have got plenty of things I want to do today bigger update tomorrow .

Dobby

Useful software Fritzing

Fritzing is a very useful program for turning your breadboard projects in schematics as I am really bad at drawing I have found it really helpful . I normally do the breadboard and then auto route the schematic .you can click here to try the software yourself .

Dobby

Rectifier diode

A diode rectifier is a semiconductor device and comes under 'active' electronic components. Its basic function is to allow the passage of electric current only in one direction and block from the other. This property also results in rectification of electric current when an AC source is used. A rectifier diode is generally recognised by its black colour and a white ring at one of its ends, something comparable to the resistor colour coding we studied in a previous article. Its size may differ with its power handling capacity. Its two ends are with two leads or terminals and hence the name diode (meaning two-legged in Greek).
A diode like all semiconductors is basically made up of pure silicon (more popular nowadays than germanium). By nature silicon is a bad conductor of electricity therefore by mixing certain impurities into it(doping), conductivity to an extent is achieved. These impurities can be positive carriers or negative carriers of charge known as p-type and n-type respectively.

In a diode the p-type and n-type silicon are fused together to form a junction called pn junction. When connected to a voltage source, this junction will restrict the flow of current from n-type to p-type and will allow the flow of current from p-type to n-type silicon, only if the voltage is more than 0.6 volts. This minimum voltage is required in any silicon semiconductor to initiate the conduction of electrons and is known as the forward-voltage. The p-type terminal of a diode is called the anode and the n-type terminal is called the cathode and is indicated by a ring or band on its body.

Shed sound system plans

Today I thought I would share the basic plans for the case for the shed sound system. Its a pretty simple cube made out of wood and held together by wood glue and screws which is then primed and painted in black it has the radio from a car in the front and  speakers on both sides of the cube with power and aerial ports on the back.

basic plan

 Other ideas I have had include mounting this into my desk or adding a subwoofer.

in other news I have began researching other projects and I have been making slow progress on the pi music box I am currently wait on parts to finish the power supply and the solder fume exactor but as soon I have the parts I will have a detail walkthrough of both projects .

Dobby

Plans for Sunday

I have a lot to do today I am planning on getting the wood to make the case for solder fume exactor as well bread boarding the circuit for it as well getting ready for the week ahead .

Other things on the list today is to track down another power supply to use with shed music system as I have been using a car battery and its now getting flat and I also need to buy a new hot glue gun as mine (10 years old ) has stopped working and I cant trace a heating element for less than the price of a new one .

Dobby

Happy days

Today has been a great day I have managed to sort a power supply for the solder fume extractor so I can now move ahead with that very soon I also looked a new work area which I think will improve my work also I have found a lcd panel to use in a retro pi arcade cabinet and I have ordered the driver board for it so I will start working on that as soon possible.

Dobby

buying components

there are two main places that I buy my components from they are eBay and Maplins .

I find eBay most use full for getting items from China and for picking up cheap components .

Maplins I use for when I need parts and components quickly mainly for when I'm repairing items for people who need there electronics back within a few hours.

I have been looking into ordering from a few other sites like component-shop , bitsbox and banggood.com all of which look promising .

I will most like place orders with all of the websites around payday and will report on my experience

Dobby

555 Timer

The 555 timer IC is an integrated circuit (chip) used in a variety of timer, pulse generation, and oscillator applications. The 555 can be used to provide time delays, as an oscillator, and as a flip-flop element. Derivatives provide two or four timing circuits in one package.
Introduced in 1972  by Signetics, the 555 is still in widespread use due to its low price, ease of use, and stability. It is now made by many companies in the original bipolar and in low-power CMOS. As of 2003^[update], it was estimated that 1 billion units were manufactured every year. The 555 is the most popular integrated circuit ever manufactured.

Pins

Pinout diagram

The connection of the pins for a DIP package is as follows:

Pin	Name	Purpose
1	GND	Ground reference voltage, low level (0 V)
2	TRIG	The OUT pin goes high and a timing interval starts when this input falls below 1/2 of CTRL voltage (which is typically 1/3 VCC, CTRL being 2/3 VCC by default if CTRL is left open). More simply we can say that OUT will be high as long as the trigger is kept at low voltage. Output of the timer totally depends upon the amplitude of the external trigger voltage applied to this pin.
3	OUT	This output is driven to approximately 1.7 V below +VCC, or to GND.
4	RESET	A timing interval may be reset by driving this input to GND, but the timing does not begin again until RESET rises above approximately 0.7 volts. Overrides TRIG which overrides THR.
5	CTRL	Provides "control" access to the internal voltage divider (by default, 2/3 VCC).
6	THR	The timing (OUT high) interval ends when the voltage at THR ("threshold") is greater than that at CTRL (2/3 VCC if CTRL is open).
7	DIS	Open collector output which may discharge a capacitor between intervals. In phase with output.
8	VCC	Positive supply voltage, which is usually between 3 and 15 V depending on the variation.

Pin 5 is also sometimes called the CONTROL VOLTAGE pin. By applying a voltage to the CONTROL VOLTAGE input one can alter the timing characteristics of the device. In most applications, the CONTROL VOLTAGE input is not used. It is usual to connect a 10 nF capacitor between pin 5 and 0 V to prevent interference. The CONTROL VOLTAGE input can be used to build an astable multivibrator with a frequency-modulated output.

Shed music sytem

After stripping my old car down today I came up with the idea to wire the old radio in it to some old speakers and make an a shed sound system its not the prettiest thing at the moment and I need to find some better speakers and tidy up the wiring but it works and it will soon be sorted ,

I also have been looking for a new I still haven't found anything in my price range sadly.

I picked up the switch for power supply today it a light up switch so I may change the plans I put up yesterday by removing the led from them .


Dobby

Solder fume extractor plans

I have finished the rough planning for a solder fume extractor it will feature two fans and a ventilation pipe leading out side to remove all traces of the fumes.

I am planning to make a wooden box as the main body of the unit with a carbon filter between the fans to help with fume removal.

a full parts list and detailed instructions  will me posted on here with pictures of every step.


here is the layout design

 Dobby

Learning Python update

After the long weekend I managed to get further into teaching myself Python I now have a much better understanding of how it works and I am continuing to improve hopefully I will soon have my own work to show.

Apart from that I have began brain storming a project using old pc fans to make a solder fume remover that will vent the fumes outside I should have the plans finished tonight and will post them tomorrow.

Dobby

Transistors

A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. It is composed of semiconductor material usually with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals controls the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. Today, some transistors are packaged individually, but many more are found embedded in integrated circuits.
The transistor is the fundamental building block of modern electronic devices, and is ubiquitous in modern electronic systems. Julius Edgar Lilienfeld patented a field-effect transistor in 1926 but it was not possible to actually construct a working device at that time. The first practically implemented device was a point-contact transistor invented in 1947 by American physicists John Bardeen, Walter Brattain, and William Shockley. The transistor revolutionized the field of electronics, and paved the way for smaller and cheaper radios, calculators, and computers, among other things. The transistor is on the list of IEEE milestones in electronics, and Bardeen, Brattain, and Shockley shared the 1956 Nobel Prize in Physics for their achievement.

Transistor as a switch

BJT used as an electronic switch, in grounded-emitter configuration.

Transistors are commonly used in digital circuits as electronic switches which can be either in an "on" or "off" state, both for high-power applications such as switched-mode power supplies and for low-power applications such as logic gates. Important parameters for this application include the current switched, the voltage handled, and the switching speed, characterised by the rise and fall times.
In a grounded-emitter transistor circuit, such as the light-switch circuit shown, as the base voltage rises, the emitter and collector currents rise exponentially. The collector voltage drops because of reduced resistance from collector to emitter. If the voltage difference between the collector and emitter were zero (or near zero), the collector current would be limited only by the load resistance (light bulb) and the supply voltage. This is called saturation because current is flowing from collector to emitter freely. When saturated, the switch is said to be on.
Providing sufficient base drive current is a key problem in the use of bipolar transistors as switches. The transistor provides current gain, allowing a relatively large current in the collector to be switched by a much smaller current into the base terminal. The ratio of these currents varies depending on the type of transistor, and even for a particular type, varies depending on the collector current. In the example light-switch circuit shown, the resistor is chosen to provide enough base current to ensure the transistor will be saturated.
In a switching circuit, the idea is to simulate, as near as possible, the ideal switch having the properties of open circuit when off, short circuit when on, and an instantaneous transition between the two states. Parameters are chosen such that the "off" output is limited to leakage currents too small to affect connected circuitry; the resistance of the transistor in the "on" state is too small to affect circuitry; and the transition between the two states is fast enough not to have a detrimental effect.

Transistor as an amplifier

Amplifier circuit, common-emitter configuration with a voltage-divider bias circuit.

The common-emitter amplifier is designed so that a small change in voltage (V_in) changes the small current through the base of the transistor; the transistor's current amplification combined with the properties of the circuit means that small swings in V_in produce large changes in V_out.
Various configurations of single transistor amplifier are possible, with some providing current gain, some voltage gain, and some both.
From mobile phones to televisions, vast numbers of products include amplifiers for sound reproduction, radio transmission, and signal processing. The first discrete-transistor audio amplifiers barely supplied a few hundred milliwatts, but power and audio fidelity gradually increased as better transistors became available and amplifier architecture evolved.
Modern transistor audio amplifiers of up to a few hundred watts are common and relatively inexpensive

Capacitors

A capacitor is a passive two-terminal electrical component that stores electrical energy in an electric field. The effect of a capacitor is known as capacitance. While capacitance exists between any two electrical conductors of a circuit in sufficiently close proximity, a capacitor is specifically designed to provide and enhance this effect for a variety of practical applications by consideration of size, shape, and positioning of closely spaced conductors, and the intervening dielectric material. A capacitor was therefore historically first known as an electric condenser.
The physical form and construction of practical capacitors vary widely and many capacitor types are in common use. Most capacitors contain at least two electrical conductors often in the form of metallic plates or surfaces separated by a dielectric medium. A conductor may be a foil, thin film, sintered bead of metal, or an electrolyte. The nonconducting dielectric acts to increase the capacitor's charge capacity. Materials commonly used as dielectrics include glass, ceramic, plastic film, paper, mica, and oxide layers. Capacitors are widely used as parts of electrical circuits in many common electrical devices. Unlike a resistor, an ideal capacitor does not dissipate energy.
When two conductors experience a potential difference, for example, when a capacitor is attached across a battery, an electric field develops across the dielectric, causing a net positive charge to collect on one plate and net negative charge to collect on the other plate. No current actually flows through the dielectric, however, there is a flow of charge through the source circuit. If the condition is maintained sufficiently long, the current through the source circuit ceases. However, if a time-varying voltage is applied across the leads of the capacitor, the source experiences an ongoing current due to the charging and discharging cycles of the capacitor.
Capacitance is defined as the ratio of the electric charge on each conductor to the potential difference between them. The unit of capacitance in the International System of Units (SI) is the farad (F), defined as one coulomb per volt (1 C/V). Capacitance values of typical capacitors for use in general electronics range from about 1 pF (10⁻¹² F) to about 1 mF (10⁻³ F).
The capacitance of a capacitor is proportional to the surface area of the plates (conductors) and inversely related to the gap between them. In practice, the dielectric between the plates passes a small amount of leakage current. It has an electric field strength limit, known as the breakdown voltage. The conductors and leads introduce an undesired inductance and resistance.
Capacitors are widely used in electronic circuits for blocking direct current while allowing alternating current to pass. In analog filter networks, they smooth the output of power supplies. In resonant circuits they tune radios to particular frequencies. In electric power transmission systems, they stabilize voltage and power flow. The property of energy storage in capacitors was exploited as dynamic memory in early digital computers.

Back to the grind

The Easter weekend is over and its nearly time to head back to work sadly the car hasn't been saved so I will have to look for a new one but apart from that I've had a great Easter weekend although I have really got much done.

on Saturday I got another diy kit which I will be sharing in future updates also the pc I picked up the other day has now been stripped down and the parts sorted ready for the projects to come .

Hopefully this week will have better updates for you and with lots of interesting content for everyone reading this

Dobby

Resistors

handy guide I use to identify resistors values  

A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. In electronic circuits, resistors are used to reduce current flow, adjust signal levels, to divide voltages, bias active elements, and terminate transmission lines, among other uses. High-power resistors that can dissipate many watts of electrical power as heat may be used as part of motor controls, in power distribution systems, or as test loads for generators. Fixed resistors have resistances that only change slightly with temperature, time or operating voltage. Variable resistors can be used to adjust circuit elements (such as a volume control or a lamp dimmer), or as sensing devices for heat, light, humidity, force, or chemical activity.
Resistors are common elements of electrical networks and electronic circuits and are ubiquitous in electronic equipment. Practical resistors as discrete components can be composed of various compounds and forms. Resistors are also implemented within integrated circuits.
The electrical function of a resistor is specified by its resistance: common commercial resistors are manufactured over a range of more than nine orders of magnitude. The nominal value of the resistance falls within the manufacturing tolerance, indicated on the component.

hope you find this info helpful

Dobby

Happy Easter

Hope everyone has had a good Easter.

My Easter has mainly consisted of laying on my back under my Vauxhall Astra cursing it but its almost ready to drive once again but apart from that I went to pick up a pc that isn't working that plan to use in few projects .

I just about to continue researching for the pi jukebox project hopefully I will have some more info for you on that soon .

I'm thinking about putting up some longer format product reviews when I get a better camera

Dobby

Getting on top of problems

Today I will be fixing my car as the head gasket has gone and I need to get it back on the road asp so I will be getting dug in on that today which does mean my electronics projects will have to take a back seat hopefully it will only take a few hours although I haven't changed a head gasket before but I have a book and will hopefully.

Other things to sort my entertainment system as I have a mess of wires stuck behind the TV and it looks untidy and is hard to unplug anything I may even add a Kodi to it .

Now to update you on the pi jukebox I'm having trouble getting the software to work how id like and think I may need to change the code so that I can make an easier front end I will keep you updated with the progress.

Finally I have ordered a digital camera to hopefully it will improve the pictures .

Dobby

good tech friday

It has been a busy day of tech and other fun things I was able to get the some more of coding for beginners in easy step book done and been bread boarding  the sound to light kit that I picked up the other day so hopefully tomorrow I will get round to soldering it up this weekend looking forward to getting even more done over done

Dobby

A quick update

It's another busy day for me with long weekend ahead which I am hoping to get a lot done to share on here sorry for the short update

Dobby

Diy sound to light kit parts

so I'm planning putting together a diy light to sound kit I got from Maplins hope I will get it done on good Friday but for today I thought  I would show all the parts that came in the kit

Board

 dimmer

electrolytic capacitor

 transistor

 mic

 red led's

 resistors

 capacitors

Dobby

project update

Just a quick  update on how things are going with the pi jukebox I now have the basic parts for the project and I am just working on how to put it all together and a good way to present it on here eg photos and maybe video

Dobby

Monday Struggles

why is Monday so far away from Friday ? yet Friday is so close to Monday ?

In my work life is mainly tech free as I work in a warehouse picking items which is about as fun as watching paint dry so I find it really hard to get motivated for my 9 to 5 anyway enough moaning about that . I've been thinking that I need to take better picutres of my projects I'm working on I've been using my IPhone to take the photos that I have put up I'm planning on getting a digtital camera improve this and hopefully make the content better for the people reading this  .

Dobby

Plans for sunday

It's Sunday the day of rest so they say I find it to my most busy getting everything ready for the week ahead so I thought Id share my plans for this lovely day.

Its a rare day here in England its not raining and the sun has well and truly got his hat on so the plan is to get out in the garden and sort out the shed so I can start working in again then get the stick welder out and teach myself how to weld as I feel that will really help with future projects I have planed like  a tech infused  go kart .

once I'm finished in the garden I will carry on teaching myself python

have a great day folks

Dobby

Breadboard tinkering

Just a quick post today as I have a load to do but here are a few pictures of breadboard projects I've been fiddling with over the last few days.

Dobby

£5 Arduino clone board review

having spent an evening using the Arduino clone that I got from Ebay .

I found it worked just as well as a more costly model .capable of doing everything you want it too  connecting  to the Arduino IDE perfectly which can be found at https://www.arduino.cc/.the only small problem I have with this board is a small bit of miss soldering see picture but apart from that its fine.

first project the blink test

What projects should I make using Arduino at the core ?



Dobby

£5 Arduino UNO like board test begins

Today I got a Arduino UNO like board from Ebay it cost £5.29  I will be testing it out over the next few days and will put a full review of the board including links to were I got it , pictures and more in the next few days depending on work and other life commitments .

Dobby

project update

so after some searching for a program to use with the pi I've chosen to use pimusicbox you can find more info about it here .

more info coming  soon

Dobby

looking to start a new project

so its Tuesday and I've decided that its time to start a new project to write about on here and possibly post on You tube .

I have been thinking that the project will be based of a raspberry pi and will most likely be some form of home entertainment system maybe a jukebox as I haven't seen many of those about .

Dobby

Learning code

I've recently started teaching myself to code and I'm really enjoying it mainly due to the book I'm using .

The book I'm using is Coding for Beginners from in easy steps and is written by Mike McGrath it mainly covers  Python programing which can be used for a number of different tasks and projects that I hope to share with you in the future.

The book is very easy to use and I'm flying  through  it at a hares pace  I can feel my skills improving every time I pick it up.

 

Here is the last thing I competed from the book

Dobby

Welcome to my first day of blogging

A little about me

Hi I'm Robert Russell from England most people who know me call me Dobby I'm currently 28 years old and I am writing this blog to share my interest and hobbies with others .

My hobbies include electronics , comics, retro gaming and other tech related projects .

I am currently learning python and will be sharing my journey on here .

I hope anyone that reads this will find future updates entertaining and informative

Dobby