Tuesday, April 30, 2013

Infrared Radar System

Chris from PyroElectro.com has a great article about a do-it-yourself radar system build with PIC18F452. It’s a great hobby project although the schematic is very complicated. This project uses three main devices to create the personal radar system. The IR Range sensor gives output, the pic microcontroller processes it and then displays the output on the led array.

  Infrared Radar Circuit Schematic
Circuit Project: DIY Infrared Radar System
The goal of this project is to create a working ir radar system. The system will only be required to measure close proximity at an angle of 90 degrees as seen in the example above. The range of system is roughly 4-30cm, 20-150cm & 1m-5.5m depending upon which sensor you choose to use.
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Friday, April 26, 2013

Easy to Use FM Radio Receiver

The project is a user-friendly and cheap FM radio receiver which produces the desired audio signals using integrated circuit to achieve the pre-processing units. During operation, the user is allowed to change stations and interact with the receiver by integrating a keypad and an LCD for communication. There are several functions that this radio receiver can perform including adjusting the threshold when picking up stronger or weaker stations, setting up 3 favorite stations for quick tuning, scanning up/down for next strong signal station, and tuning up/down a frequency.

Hacks and Mods:Easy-To-Use FM Radio Receiver
A keypad is designed for controlling the receiver and the buttons are mapped to their corresponding functionality while the other buttons are not connected. The 4 main sub-components of the receiver include the LCD, the keypad, the favorite station storage, and the communication with receiver. Each of them is being controlled by their software components. The antenna transfers the incoming radio signal to the AR1010 FM radio receiver. To communicate with the AR1010, the I2C protocol is used since the sample code is available online. Also, the AR1010 is powered by 3V. The button presses on the keypad are scanned by the program.
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Saturday, April 13, 2013

Power On Indicator

Some sorts of electronic gear do  no longer provide any indication that they are  in fact on when they're switched on.  This situation can occur when the back-light of a show is switched off. In addition, the otherwise mandatory majors  power  indicator  is  now not  required  with  tools  that  devours  less  than  10 watts. As a outcome, you can simply forget  to modify off such gear. If you want  to grasp whether or not gear continues to be drawing power from the mains, or in case you want  to have a sign that the gear  is switched on without needing to switch the equipment, this circuit offers an answer. 

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One way to realize AC power current and  generate a reasonably consistent voltage  impartial of the load is to attach a  string of diodes wired in reverse parallel in collection with some of the AC supply  leads. Here we chosen diodes rated  at 6 A that may just handle a non-repetitive  peak current of 200 A. The top current  score is vital in connection with  switch-on  currents.  An  advantage  of  the selectedn diodes is that their voltage  drop will raise at high currents (to 1.2 V  at 6 A). This method you may roughly  estimate the energy consumption from  the brightness of the LED (at very low  power degrees). The voltage across the diodes serves as  the supply voltage for the LED driver. To  raise the sensitivity of the circuit, a  cascade circuit (voltage doubler) which incorporates C1, D7, D8 and C2 is used to double  the voltage from D1–D6. Another benefit  of this association is that each halve- waves of the AC present are used. We use  Schottky diodes in the cascade circuit to  minimise the voltage losses. 

Circuit diagram :
Power On Indicator Circuit Diagram

The LED forcer is designed to operate the LED  in blinking mode. This increases the amount  of current that could float though the LED when  it's on, so the brightness is sufficient even  with small hundreds. We selected a duty cycle of pproximately 5 2ds off and zero.5 2d  on. If we assume a current of 2 mA for excellent  brightness with a low-current LED and we can  tolerate a 1-V drop in the supply voltage, the  smoothing capacitor (C2) must have a worth of  a thousand µF. We use an astable multivibrator built around two transistors to put into effect a  high-efficiency LED flasher. It is dimensioned to minimise the pressure current of  the transistors. The average current consumption is approximately zero.5 mA with a  provide voltage of three V (2.7 mA when the  LED is on; 0.2 mA when it is off). C4 and  R4 resolve the on time of the LED (0.5  to zero.6 s, depending on the availability volt-age). The LED off time is determined by  C3 and R3 and is fairly lower than 5 seconds. The theoretical value is R × C × ln2,  however the real price ranges reasonably due to  the low provide voltage and the selectedn  component values.
 
Diodes D1-D6 shouldn't have to be special  high-voltage diodes; the reverse volt-age is simplest a couple of volts right here due  the reverse-parallel association. This  voltage drop is negligible in comparison to  the worth of the principles voltage. The most effective  thing you must take now note of is the  maximum load. Diodes with a excessiveer  present rating need to be used above 1 kW.  In addition, the diodes may just require cool-ing at such excessive power stages.  Measurements on D1–D6 indicate that  the voltage drop throughout each diode is  approximately 0.4 V at a present of 1 mA.  Our purpose was once to have the circuit give a  affordable indication at current levels  of 1 mA and excessiveer, and we succeeded  effectively. However, it's essential to make use of a  excellent low-current LED.
 
Caution: the entire circuit is at AC power doable. Never work on the circuit with the primarys cable plugged in. The  best possible enclosure for the circuit is a small,  translucent field with the identical color as  the LED. Use reliable pressure aids for the  primarys cables getting into and leaving the  box (connected to a junction box, for  example). The LED insulation does now not  meet the necessities of any outlined insulation category, so it should be equipped such that it  can't be touched, which means that it cannot  protrude from the enclosure.
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Thursday, April 11, 2013

Antenna Tuning Unit ATU For 27 MHz CB Radios

This antenna
tuning unit (ATU) enables half-wavelength or longer wire antennas to be
matched to the 50-? antenna input of 27-MHz Citizens’ Band (CB) rigs.
The ATU is useful in those cases where a wire antenna is less obtrusive
than a roof-mounted ‘vertical’ or ground-plane. It is also great for
‘improvised’ antennas used by active CB users on camping sites and the
like because it allows a length of wire to be used as a fairly
effective antenna hung between, say, a tree branch at one side and a
tent post, at the other. Obviously, the wire ends then have to be
isolated using, for example, short lengths of nylon wire. It is even
possible to use the ATU to tune a length of barbed wire to 27 MHz. The
coil in the circuit consists of 11 turns of silver-plated copper wire
with a diameter of about 1 mm (SWG20).

The internal diameter of
the coil is 15 mm, and it is stretched to a length of about 4 cm. The
tap for the antenna cable to the CB radio is made at about 2 turns from
the cold (ground) side. Two trimmer capacitors are available for tuning
the ATU. The smaller one, C1, for fine tuning, and the larger one, C2,
for coarse tuning. The trimmers are adjusted with the aid of an
in-line SWR (standing-wave ratio) meter which most CB enthusiasts will
have, or should be able to obtain on loan. Select channel 20 on the CB
rig and set C1 and C3 to mid-travel. Press the PTT button and adjust C2
for the best (that is, lowest) SWR reading. Next, alternately adjust
C3 and C2 until you get as close as possible to a 1:1 SWR reading.

Antenna Tuning Unit (ATU) For 27-MHz CB RadiosC1
may then be tweaked for an even better value. No need to re-adjust the
ATU until another antenna is used. In case the length of the wire
antenna is exactly 5.5 metres, then C3 is set to maximum capacitance.
Although the ATU is designed for half-wavelength or longer antennas, it
may also be used for physically shorter antennas. For example, if
antenna has a physical length of only 3 metres, then the remaining 2.5
metres has to be wound on a length of PVC tubing. This creates a
so-called BLC (base-loaded coil) electrically shortened antenna. In
practice, the added coil can be made somewhat shorter than the
theoretical value, so the actual length is best determined by trial and
error. Finally, the ATU has to be built in an all-metal case to prevent
unwanted radiation. The trimmers are than accessed through small
holes. The connection to the CB radio is best made using an SO239
(‘UHF’) or BNC style socket on the ATU box and a short 50-W coax cable
with matching plugs.
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Tuesday, April 9, 2013

Single Chip VHF RF Preamp

Here is a high
performance RF amplifier for the entire VHF broadcast and PMR band
(100-175 MHz) which can be successfully built without any special test
equipment. The grounded-gate configuration is inherently stable without
any neutralization if appropriate PCB layout techniques are employed.
The performance of the amplifier is quite good. The noise figure is
below 2 dB and the gain is over 13 dB. The low noise figure and good
gain will help car radios or home stereo receivers pick up the
lower-power local or campus radio stations, or distant amateur VHF
stations in the 2-metres band. Due to the so-called threshold effect, FM
receivers loose signals abruptly so if your favourite station fades in
and out as you drive, this amplifier can cause a dramatic improvement.
The MAX2633 is a low-voltage, low-noise amplifier for use from VHF to
SHF frequencies.


Single-Chip VHF RF Preamp circuit schematic

Operating
from a single +2.7V to +5.5V supply, it has a virtually flat gain
response to 900 MHz. Its low noise figure and low supply current makes
it ideal for RF receive, buffer and transmit applications. The MAX2633
is biased internally and has a user-selectable supply current, which
can be adjusted by adding a single external resistor (here, R1). This
circuit draws only 3 mA current. Besides a single bias resistor, the
only external components needed for the MAX2630 family of RF amplifiers
are input and output blocking capacitors, C1 and C3, and a VCC bypass
capacitor, C2. The coupling capacitors must be large enough to
contribute negligible reactance in a 50-? system at the lowest
operating frequency. Use the following equation to calculate their
minimum value: Cc = 53000/ flow [pF]. Further information:
www.maxim-ic.com.
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Sunday, April 7, 2013

Surge Protected Cheap Transformerless Hi Watt LED Driver Circuit

Surge Protected Cheap Transformerless Hi Watt LED Driver CircuitThis circuit is just a proof of concept just to show that the good old 555 timer can still be used for a modern and quite demanding application. It is by no means an optimized circuit that can be readily used for mass production. It appears relatively big by today's standard because I used only through hole components. You may shrink it to 50 % of its original size if you use modern SMD parts. You may also be able to increase the efficiency of this circuit. Unfortunately I didnt't have time to do extensive measurements with all sorts of inductors. There may be some room for optimizations.
Surge Protected Cheap Transformerless Hi Watt LED Driver Circuit

Parts list

R1 2.2 kΩ / 0.1 W
R2 10 kΩ / 0.1 W
R3 100 kΩ / 0.1 W
R4 470 Ω / 0.1 W
R5 1 kΩ / 0.1 W
R6 2 Ω / 0.25W
C1 220 pF NPO ceramic disc capacitor
C2 10 µF / 16 V electrolytic
C3, C4 470 µF / 6.3 V, low ESR
L1 custom made transformer, see text
L2 47 µH / 2 A (TDK SLF 12575 / Fastron PIS4728 series)
D1 1N4148
D2 SB240 (SB360, MBRS240, MBRD650)
D3 BZX55C 4V7, 4.7 V Zener Diode
D4 1 W High Power LED
T1 BC 337-40 (2N2222A)
T2 BC547B (2N3904)
T3 2SK2869 (IRLR2905, IRLZ 34N)
IC1 ICM7555 (TLC555, HA17555)
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50W car audio amplifier schematic

50W car amplifier schematicsCar power amplifier uses SI1050GL IC as the main amplifier. The output power 50 Watt 8 ohm mono impedance. Up to 25 Volt DC voltage. with source voltage of this amplifier car battery has to work.




Minimum of 12 Volt battery voltage, less than a sound or audio is issued less than the maximum and less good. You can assemble  this circuit amplifier with a schema like this.
50W car amplifier system
Part List
R1 = 100K
R2 = 1R
C1 = 2.2uF
C2 = 22uF
C3 = 100uF
C4 = 0.1uF
C5 = 100uF
U1 = SI1050GL
If you want to make stereo amplifier , you must required multiply the two of components. 


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Friday, April 5, 2013

Cable Tester

This cable tester allows you to quickly check audio cables for broken wires. Because of the low power supply voltage, batteries can be used which makes the circuit portable, and therefore can be used on location.

Cable Tester Circuit diagram:

Simple Cable Tester-Circuit Diagram

The design is very simple and well organ-ised: using the rotary switch, you select which conductor in the cable to test. The corresponding LED will light up as indication of the selected conductor. This is also an indication that the power supply volt-age is present. If there is a break in the cable, or a loose connection, a second LED will light up, corresponding to the selected conductor. You can also see immediately if there is an internal short circuit when other than the corresponding LEDs light up as well.

You can also test adapter and splitter cables because of the presence of the different connectors.
Two standard AA- or AAA- batteries are sufficient for the power supply. It is recommended to use good, low-current type LEDs. It is also a good idea not to use the cheapest brand of connectors, otherwise there can be doubt as to the location of the fault. Is it the cable or the connector.

Source:   http://www.ecircuitslab.com/2012/06/simple-cable-tester.html
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Wednesday, April 3, 2013

Drilling Floor Rear Light Rear Light Mounted

Basic Electrical Wiring on Basic Electrical Wiring  Edward L  Safford  Amazon Com  Books
Basic Electrical Wiring Edward L Safford Amazon Com Books.


Basic Electrical Wiring on Da Solar Car  Basic Electrical Wiring Diagram
Da Solar Car Basic Electrical Wiring Diagram.


Basic Electrical Wiring on The Motorcycle Electrical System And Components Sound And Appear Very
The Motorcycle Electrical System And Components Sound And Appear Very.


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Speaking Of 3 Wire Cable Romex 12 3 Has A Black Wire For Hot A Red.


Basic Electrical Wiring on Framed Building Or Residential Home With Basic Electrical Wiring And
Framed Building Or Residential Home With Basic Electrical Wiring And.


Basic Electrical Wiring on Big Steps In Building  Change Our Wiring To 12 Volt Dc   Treehugger
Big Steps In Building Change Our Wiring To 12 Volt Dc Treehugger.


Basic Electrical Wiring on Basic Wiring For  81 Cj7
Basic Wiring For 81 Cj7.


Basic Electrical Wiring on Electrical Wiring   Let S Talk Basic Residential Wiring
Electrical Wiring Let S Talk Basic Residential Wiring.


Basic Electrical Wiring on Basic Electrical Outlet Wiring
Basic Electrical Outlet Wiring.


Basic Electrical Wiring on Drilling Through The Floor For The Rear Light Rear Light Mounted
Drilling Through The Floor For The Rear Light Rear Light Mounted.


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Monday, April 1, 2013

Structured Wiring Connecticut

Structured Wiring on Structured Wiring
Structured Wiring.


Structured Wiring on Advanced Cabling   Security  Structured Wiring
Advanced Cabling Security Structured Wiring.


Structured Wiring on Structured Wiring Connecticut
Structured Wiring Connecticut.


Structured Wiring on Structured Wiring Boom Creates Job Opportunities
Structured Wiring Boom Creates Job Opportunities.


Structured Wiring on Structured Wiring Is Very Different Than The Older Way Of Doing
Structured Wiring Is Very Different Than The Older Way Of Doing.


Structured Wiring on Structured Wiring Connecticut
Structured Wiring Connecticut.


Structured Wiring on Lifestyle Electronics   Structured Wiring
Lifestyle Electronics Structured Wiring.


Structured Wiring on Structured Wiring Systems Installation
Structured Wiring Systems Installation.


Structured Wiring on Structured Wiring Panel1 Jpg
Structured Wiring Panel1 Jpg.


Structured Wiring on Products  Swan Structured Wiring Audio Network   Ada
Products Swan Structured Wiring Audio Network Ada.


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