Product areas:
Low Power (battery)
Consumer
Medical
Industrial
Military
Data Acquisition
Machine Controls
Navigation Equipment
Communications
Automotive Test Equipment
Disk/Tape Drives

Computer Solutions Employees: 4-9
AVR experts: 1-3 George Jerome
george@ecoology..
9565 Vassar Ave, Chatsworth, CA 91311
Tel: +1 (818) 407-1235
Fax: +1 (818) 998-2665
Flexible solutions to control problems utilizing in-circuit programmable Atmel AVR microprocessors for industrial, aviation, medical, and commercial applications. Sensor inputs, analog inputs, digital interface, inter-device communications, high-level language programming, as well as assembly coding for tight, fast program execution. Experience with UL, FAA, and FCC regulatory agencies. More than 35 years of hands-on design experience. Design and development of new products, fault-finding and correction of existing products, and function enhancement of otherwise obsolete devices. Capabilities include hardware design, software development, packaging, PCB design, and prototype assembly. In-house machine shop. Experienced in Industrial controls, aviation related systems, medical, telephone, energy conservation, inspection, HVAC controls, environmental systems, machine tools, and manufacturing machines.
Digital Systems Associates, Inc. Employees: 4-9
AVR experts: 4-9 David Switzer
dkswitzer@dsanet..
11401 La Vereda Dr.
Suite 200
Santa Ana, CA 92705-7405
Tel: +1 (714) 838-2495
Fax: +1 (714) 838-2497
DSAI has a 20-year track record providing embedded systems development and consulting services to commercial, industrial, and governmental clients. Building on a core team of senior personnel with demonstrated capabilities, DSAI is able to provide system design consulting services as well as hardware, firmware and software contract development services in a variety of application areas including:
Real-time embedded systems
Monitoring and control
Peripheral device and controller firmware (disk, tape, data communications, networking)
Device drivers
Instrumentation and test equipment
Data communications
Protocol stacks
Windows API and .NET, MS-DOS and Embedded Linux test and application programs

Gordon Minns & Associates Employees: 1-3
AVR experts: 1-3 Gordon Minns, Ph.D.
gminns@minns..
7631 E. Greenway Rd. Scottsdale, AZ 85260
Tel: +1 (480) 215-1340
Fax: +1 (480) 991-2393
Turn-Key Product Design Solutions in Medical/Dental, Industrial, and Consumer Electronics.

Full range of product development services:
Analog, sensor, digital circuit design
AVR and other microprocessor software in C and assembly language
Industrial Design using 3D software, Tooling and Packaging
FDA, CE, UL , FCC and other regulatory agency approvals
Sub-systems and enhancements for new and existing products
Experience in:
Medical/Dental products, including life support systems, Automated test fixtures
Digital Audio/Video, Sensors and Data Logging, Ethernet-based remote control and monitoring
Industrial, machine tool, and HVAC controllers

Gottlieb Inventions, Inc. Joseph Gottlieb
ginvent@pacbell.net
1305 Simpson Wy.
Suite G
Escondido, CA 92029
Tel:+1 (760) 743-2006
Fax:+1 (760) 743-2006
Gottlieb Inventions, Inc. is a product manufacturer as well as design consultant. We have expertise in analog, digital, RF, PCB, and control system design. From quick, low cost designs to complex integrated systems, we run the full range of capabilities. We handle software, hardware, and pcb design for atmel AVR microcontrollers.
JTZ Engineering Employees: 1-3
AVR experts: 1-3 John T. Zigrang
jtz@jtzeng..2462 W. 230th St.
Torrance, CA 90501
Tel: +1 (310) 534-8559
Fax: +1 (310) 534-1084
Even though we are located in Southern California, JTZ works with companies all over the world. Established in 1985, JTZ Engineering, Inc. is a full time design company actively involved in consumer and industrial product development specializing in the Security Industry, Printer Controllers, Test Environment Support and Control Subsystems. We have been working successfully with AVR controllers since 1999.

Recent experience includes:
Aircraft system tester
Access Control Systems for the Safe and Banking industries
Communications interfaces for data conversion and collection
Battery operated devices for multi-year operation
Fuel control subsystems
Real Time audio control system
Inspection Equipment controller
Dallas TAG devices for security applications
DC/DC converters, Step Up or Step Down
Our designs have been produced at production levels of 3000 a week, to 100 a year. Whatever the size of your project, JTZ can assist in getting your ideas to market. We also have experience with very large project and have a number of associates that can be called in if needed. At JTZ we are able to do full product development including system design, layout and packaging, with surface mount designs as a specialty. We also provide services for low volume production and management of contract manufacturing for our designs. JTZ has also set up in-house manufacturing for clients just starting in electronic products.

Project outlines and/or design requirements can be emailed to jtz@jtzeng.. for quoting. Or you can start by contacting Kaye for more information on JTZ and to set up an appointment.
Laritech, Inc. Employees: 10-30
AVR experts: 1-3 Bill Larrick
Infra Red Remote Control Extender
Circuit : Andy Collinson
Email: anc@mitedu.freeserve.co.uk

Description
This circuit is used to relay signals from an Infra Red remote control in one room to an IR controlled appliance in another room.

Forward
I have seen these devices advertised in magazines, they sell for around ￡40-￡50 and use radio to transmit between receiver and transmitter. This version costs under ￡5 to make and uses a cable connection between receiver and transmitter. For example, if you have a bedroom TV set that is wired to the video or satellite in another room, then you can change channels on the remote satellite receiver using this circuit. The idea is that you take your remote control with you, aim at the IR remote control extender which is in the same room, and this will relay the IR signal and control the remote appliance for you. The circuit is displayed below:

Parts List:
1 SFH2030 Photodiode
1 TIL38 IR emitting diode
1 5mm Red LED
2 4.7M 1/4W resistors
1 1k 1/4W resistor
1 2.2k 1/4W resistor
1 27ohm 1/2W resistor
1 BC337 transistor
1 CA3140 MOSFET opamp
The CA31340 is available in the US from Electronix Express, part number N103140.

Circuit Advantages
The advantage of this design against similar designs is that there are no adjustments to make or set-up procedures. However care should be taken to avoid ambient light reaching the photodiode. A dayligt filter type (black in colour) is recommended. Bellwire or speaker cable may be used to remotely site the IR emitting diode, since this design uses low output impedance and will not pick up noise. Some systems require coaxial cable which is expensive and bulky. The wireless variety of remote control extenders need two power supplies, here one is used and being radio are inevitably EM noise pollution. A visual indication of the unit receiving an Infra Red signal is provided by LED1. This is an ordinary coloured LED, I used orange but any colour will do. You will see LED1 flash at a rate of 4 - 40Hz when a remote control button is pressed. LED0 is an Infra Red Emitter Diode, this is remotely wired in the room with the appliance to be controlled. I used the type SFH487 which has a peak wavelength of 880nm. This is available in the UK from Maplin Electronics, order code CY88V. Most IR remote controls operate at slightly different wavelengths, between the range of 850 - 950nm. If you cannot obtain the SFH487 then any IR emitter diode that has an output in the above range should work.

About IR Remote Controls
As previously stated IR remote controls use wavelengths between 850 - 950nm. At this short wavelength, the light is invisible to the human eye, but a domestic camcorder can actually view this portion of the electromagnetic spectrum. Viewed with a camcorder, an IR LED appears to change brightness. All remote controls use an encoded series of pulses, of which there are thousands of combinations. The light output intensity varies with each remote control, remotes working at 4.5V dc generally will provide a stronger light output than a 3V dc control. Also, as the photodiode in this project has a peak light response at 850nm, it will receive a stronger signal from controls operating closer to this wavelength. The photodiode will actually respond to IR wavelengths from 400nm to 1100nm, so all remote controls should be compatible.

Circuit Description
The receiver is built around a silicon photodiode, the SFH2030 available from Maplin, order code CY90X. This photodiode is very sensitive and will respond to a wide spectral range of IR frequencies. There is a small amount of infra red in direct sunlight, so make sure that the diode does not pick up direct sunlight. If this happens, LED1 will be constantly lit. There is a version of the SFH2030 that has a daylight filter built in, the SFH2030F order code CY91Y. A TIL100 will also give good results here. A photodiode produces minute pulses of current when exposed to infra red radiation. This current (around 1uA with the SFH2030 and a typical IR control used at a distance of 1 meter) is amplified by the CA3140 opamp. The opamp is configured as a current to voltage convertor, producing an output of about 4.7 volts per uA of input current. The photodiode, can be placed up to a meter or so away from the circuit. Screened cable is not IR Remote Control Lab
Module by: Casey Weltzin

Summary: Infrared signals are commonly used to transmit information between phototransmitters and photoreceivers. In this lab, a photodiode and Low Cost National Instruments USB DAQ are used to detect the presence of an infrared signal. The IR Remote Control lab is designed as a labratory or at-home experiment.

IR Remote Control Using National Instruments Low Cost Data Acquisition
Introduction
Have you ever wondered how a typical remote control works? When the user presses a button on the remote, an infrared signal is transmitted across the room and detected by a sensor called a photodetector. You will create a remote control of your own in this exercise.

In this lab, you will use a standard universal remote control to transmit an infrared signal several feet. A detection circuit will then be constructed using a specific type of photoreceiver known as a photodiode. Next, a Low Cost USB DAQ device will be used to digitize the infrared signal. Finally, this digitized signal will be analyzed using LabVIEW software to control the popular iTunes application with the help of ActiveX controls.

Pre-Lab Assignment
1) Why can’t humans see the infrared light coming out of a remote control? Look online or in a textbook to find the wavelengths of the visible light spectrum as well as the wavelengths of the infrared light spectrum.

2) Write a short summary about how the photodiode works. You should be able to find a variety of sources online; cite them in your response.

3) Search Google for “infrared photodiode datasheet」 and see what you can find. What specifications are common for photodiodes? Verify that the photodiode detection range is within the infrared spectrum.

4) To generate the infrared signal, your remote control contains an infrared LED. Find an infrared LED datasheet online. What specifications do you see? Verify that the infrared LED emission range is within the infrared spectrum.

5) Become familiar with the National Instruments USB 6008 and 6009 data acquisition devices. These datasheets are available at www.China-low-cost-PCB.org.......ni...

Theory
Infrared signals are very similar to visible light, except they occupy a section of the electromagnetic spectrum that makes them invisible to the human eye. In scientific terms, the infrared spectrum contains wavelengths ranging from approximately 1.0 mm to 0.7 um. It is convenient to use infrared signals for remote control transmission, because their reception is not strongly affected by the amount of ambient light present at the photodetector.

One common method of converting an infrared remote control signal (0.7 – 0.9 um wavelength) into an electrical signal is using an infrared photodiode. In addition, another method is using a phototransistor. For this laboratory exercise, we will focus on an infrared photodiode transducer similar to the one shown below:Infrared circuits for remote control
description
Infrared remote controls are using a 32-56 kHz modulated square wave for communication. These circuits are used to transmit a 1-4 kHz digital signal (OOK modulation) through infra light (this is the maximum attainable speed, 1000-4000 bits per sec). The transmitter oscillator runs with adjustable frequency in the 32-56kHz range, and is being turned ON/OFF with the modulating signal, a TTL voltage on the MOD input. On the receiver side a photodiode takes up the signal. The integrated circuit inside the chip is sensitive only around a specified frequency in the 32-56 kHz range. The output is the demodulated digital input (but usually inverted), just what we used to drive the transmitter. When the carrier is present, this output is usually low. When no carrier is detected, the output is usually high.

Stefan Ovidiu writes that if you'd need a low power device, replace the NE555 IC with an ICM7555 (the CMOS equivalent of 555) or use a quad NAND CD4011 to build a gated oscillator.

FAQ
Q: I need 2 IR receivers & transmitters that don't affect each other (for example a remote control for a PANASONIC TV & a SONY TV) and work separately.

A: Please check my codec page @ http://jap.hu/electronic/codec.html You can use the 555 transmitter and the IC receivers with them. If you don't have the expertise in PIC programming to modify the code to suit your needs, you can consider the MC145026-8 IC-s. Check the datasheets and you can build transmitters & receivers with unique ID-s, so you can match them to each other.

links
my serial port controlled IR transmitter
a serial-driven infrared transmitter
serial port receivers
UIR: universal infrared receiver for PC
another infrared receiver for serial port
How IR stuff works & details about the Philips RC-5 infrared modulation scheme Electronics circuit project and link collections in this site
Audio circuits
Computer hardware circuits
Data communication circuits
Electrical motor controlling circuits
Electronics circuit designs by Tomi Engdahl
IR remote control circuits
Light controlling electronics
Music circuits
Oscillator circuits
Power supply circuits
PC related electronics circuits
Telephone circuits
Video circuits

Electronics circuit sites
Note on using the circuits on the sites: There is no guarantee that the circuits in the following sites are entirely correct or working. Be sure you understand completely their posted information before you buy any parts. Most of the circuits seem to be good ones, but there are circuit diagrams with errors or essential information missing.

You can browse the circuits sites listed below to find lots of interresting circuits. If you are interrested in quicly browsing for a specific circuit, you can use circuit sites search engine to search for the circuits listed in those sites.

Circuit site search
This circuits sites search engine tries to index the circuits in those sites so you can search the contes of circuit sites listed below (it has most of the circuits from those sites in database, but not all of them because some sites are not automatically indexable).

Circuit site list

2304 Tech List - Many radio atenna building project documents on-line. Pages have also many radio equipment plans on-line.
4QD Electronics Circuits Reference Archive - 4QD's pages of interesting circuits with wide selection of small circuits useful as building blocks for electronic systems
Aaron's Electronic Circuits - light, laser, sound, radio, PSU, car
Alfred73 Electronics - SMT Desoldering Station, Infrared Receiver, line in use, VGA to TV, power supply
Amateurfunk- und Elektronik-Projekte - amateur radio electronics project in German
Amateur Radio Construction Projects
Amazon Electronics Free Circuits - audio, computers, controllers, testers, light effects, microcontrollers, power supplies, radio, security, timers, circuit can be also bought as complete kits from Amazon Electronics
Ampage - guitar effects and music electronics
AMZ Projects - audio effects circuits, mixer
Analog Devices Audio Circuits Application Notes
Analog Devices Application Notes Libraty - information and circuits on A/D-converters, D/A-converters, accelerometers, DSP, analof audio, digital audio, measurements, communication, motor control, signal processing, oscillators, amplifiers, RF, temperature and signal conversion
Analog Innovations S.E.D Postings & Schematics
Analog Innovations Subcircuits & PSpice Symbols
Analog Music Zone Guitar Effects Schematics - guitar effects, compressors, microphones and effects
Andrew Buckin Projects - VGA generator, SVGA generator, IDE2LPT, CPLD projects
Antenna Scope, Attenuators,RF Probe, MORE!
Applications of neon glow lamps - some applications of neon glow lamps
Aquarium Related Electronics - pH meters, thermometers
Aren's Attic: How to build your own audio equipment - loudspeakers, solid-state amplifiers and tube amplifiers
Audio Designs Guide
Audio Electronics Page - amplifiers, preamplifiers, power supplies
Batronix.. - electronic circuits, information, software and datasheets to download for electronics hobbyists, programmers for EPROMs and microcontrollers
Batronix.. Electronics Circuits and Layouts Library
Bebek Electronics Kits - tghis describes electronics kits for various applications, circuit diagram for most can be found on the kit pages, this site is in Finnish but most circuits can be understood by viewing just pictures, some circuit diagrams have text in English
Beyond Logic - PC interfacing projects
Bob Blick's Projects for Students and Hobbyists
Body Build Articles - Here are some hardwere interfacign articles published in Micro User or Acorn Computing from from March 83 to March 95.