The vacuum tube is still alive and useful in some applications, as in this CW transmitter, The circuit was built in old-fashioned breadboard style on a wooden base. Old table radios are a good source of parts for this circuit. V3 is used as a ballast resistora 75- or 100- 5-W resistor could be substituted. LI is 15 turns of hookup wire on a form 2 long...
The physical circuit layout is extremely critical. Breadboarding is not recommended. ..
This is a simple, cheap device that can be connected to any serial port to control most components that have infrared remote controls. I designed and built it (on a solderless breadboard) in 1991. In 1992 I wrote a lengthy description of it for an electronics class. In 1994 I finally designed a PC board for it, using a free, X-based PC board design program called pcb, and in 1995 I etched several of the boards and made the final product...
These two projects , Wah and Fuzz, are the results of a modification to a Morley dual channel volume control pedal that one of my sons suggested I undertake as He had no use for the volume unit but thought I could modify the pedal into a Wah unit. I decided later to add a Fuzz circuit and combine the two into a single switchable unit as described further on. Not being one to re-invent the wheel, I downloaded several circuits from the Internet and after breadboarding.....
Here is a simple circuit for sequentially flashing Christmas light strings or other similar low-power lamps. The socket symbols may be single bulbs or sockets for lamp strings. The load must be capable of operating from DC since the SCRs rectify the line voltage. The circuit may be extended by repeating the pattern with the last neon lamp connecting back to the first through a capacitor. Although a quick breadboard was tested, this circuit is "experimental" and may require.....
The Lazy Adapter is composed of a 20 pin DIP socket, a 20 pin DIP header, and 6 pin ISP header, and a small phenolic circuit board to hold them all together. The green fiberglass PCB is a Dontronics DT104 SIMSTIC(This plug is in return for a favor.) I am tired of wiring up ISP sockets for every little breadboard I build, so I built this little adapter. It plugs into a 20 pin IC socket for an AVR on a breadboard. On the adapter is the 6 pin ISP header in the same.....
RF is just way too cool not to use in your designs. But if you`re a newbie like me it is difficult to successfully build solid RF transmitters and receivers. When I started out I didn`t realize that the larger breadboard I was working off of was causing a lot of the signal deviance because the metal traces on the breadboard worked like small capacitors and changed my circuit dynamics. So after much research I found the Reynolds Electronics RWS and TWS 434 RX/TX pair...
The project was originally intended as a present for my brothers dorm room, but a bad capacitor and the lack of a proper oscilloscope caused delays. It has not made it off the breadboard, and it probably will not until his next semester. The circuit contains a few basic elements, an flip-flop based oscillator, a set of delays, a flip-flop as a sensor, and the audible alarm...
This simple circuit functions as a 12 LED chaser. A single illuminated LED 'walks' left and right in a repeating sequence, similar to the effect seen on KITT, the car in the Knight Rider TV series. Fully commented source code and programmer ready HEX files are provided for the PIC 16F84A and 16F628A at the bottom of this page. The circuit has been constructed on a PCB but can easily be built on strip-board, or a solderless breadboard. This project has been put.....
This handy breadboard header for ATTiny 25/45/85 microcontroller is a new design based on the original idea from Tinkerlog. Maybe the most useful feature is that it can provide power to the vertical breadboard strips while connecting all six port pins to the horizontal strips. Other features are :6-pin ISP connector (works great with USBtinyISP programmer). easily accessible reset button. header for optional ceramic resonator. power led indicator. smoothing caps. Measuring.....
Built using a PIC16F84, about 4 hours worth of code and a few bits on a breadboard. This was the first time I've worked with PIC's so it was a learning exercise. I started with the 'Hello World' microcontroller equivalent i.e. Blinking LED, then tried the 'Knight Rider' sequencing LEDs, and then hacked this together. The code is written and assembled using the Microchip MPLAP IDE V5.70...
This circuit can be used to "sweep" an area or room and will indicate if a surveillance device is operative. The problem in making a suitable detector is to get its sensitivity just right; too much and it will respond to radio broadcasts, too little sensitivity and nothing will be heard. This project has few components, can be made on veroboard and powered from a 9 volt battery for portability. My prototype shown below, worked OK on a Eurobreadboard...
I2C are widely use for to communicate with external peripheral such as port expender, EEPROM, Real Time Clock etc. The Master Synchronous Serial Port (MSSP) module in PIC18 can be used to communicated with I2C peripheral. MSSP module can be configure to work as SPI and I2C. In this example the module will be configured as I2C to communicate with a port expender from Microchip MCP23017. The circuit below is built up on breadboard to test the MSSP function as an I2C module. ..
Continuing with the thermocouple interface concept, the next step is to amplify the TC's millivolt signal into a more readable analog voltage, on the order of 0 to 5VDC. This simple circuit fits the bill. The LM358N is a dual op-amp IC. I'm quite sure any op-amp IC would do fine, just be sure it can accept a Vcc which is compatible with your battery pack. The IC draws ~ 1.0 mA. The resistors form a feedback loop into the op-amp, with a gain described in the schematic, and.....
With a handful of inexpensive components, a little creativity, and the power of PicBasic, you can build some pretty outstanding robotics creations as Rob Arnold proves with his Ruf-Bot project. RF remote control is just way too cool not to use in your designs, but if you`re a newbie like me it`s difficult to successfully build solid RF transmitters and receivers on your own. When I started out I didn`t realize that the larger breadboard I was working off of was causing a.....
Heres a small and handy tester circuit for the DTMF IC. It can be assembled on a multipurpose PCB with an 18-pin IC base. One can also test the IC on a simple breadboard. The MT8870 is an 18-pin IC. It is used in telephones and a variety of other applications...
Operational Amplifiers
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ANSI Standards
Low Frequency Amplifiers
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