Advertisement
Mini GSM localizer without GPS – Circuit Schematic
Mini GSM localizer without GPS
A localizer without GPS. We remake the old device with the cheaper SimCom module SIM900. In the previous post we present the GSM section and now we can present ...
GSM/GPS Localizer with SIM908 module – Circuit Schematic
GSM/GPS Localizer with SIM908 module
The device is based on a GSM/GPRS module with included GPS. Its main function is to detect and communicate its own geographical position using, on the choice, t...
GSM localizer without GPS Schematic – Circuit Schematic
GSM localizer without GPS Schematic
The circuit our localizer is based on consists only of a quad-band GSM/GPRS module interfaced with a a microchip microcontroller which, after initializing the I...
Using DTT to create your own TV transmitter – Circuit Schematic
Using DTT to create your own TV transmitter
The TV transmitter we present today generates a stream containing four TV programs and broadcasts it on a frequency in the DTT standard. Ideal for stacking in a...
DTMF decoder using MT8870DE – Circuit Schematic
DTMF decoder using MT8870DE
The phone system use to be operated by human operator in a telephone exchange room. The caller will pick up the phone, giving instruction to the operator to con...
Bandwidth reduction of DXTV video – Circuit Schematic
Bandwidth reduction of DXTV video
DX TV enthusiasts often have to deal with relatively crowded VHF bands. In these instances, reduced TV receiver bandwidth results in greater selectivity. The ot...
Homebuilt Hellschreibers – Circuit Schematic
Homebuilt Hellschreibers
The circuitry for the tone detector, solenoid driver, and motor speed control (paper transport and spindle) is rather straightforward. A solid-state implementat...
Mobile Phone diagram – Circuit Schematic
Mobile Phone diagram
...
gated pulse descrambler – Circuit Schematic
gated pulse descrambler
This circuit consists of an amplifier and video detector with a second subcarrier detector for synch recovery purposes. A pulse-former circuit modulates the gai...
Global Positioning System GPS – Circuit Schematic
Global Positioning System GPS
The Global Positioning System (GPS) relies on more than two dozen GPS satellites orbiting the Earth. Each satellite transmits signals including a very precise c...
N1FN Key Collection – Circuit Schematic
N1FN Key Collection
A Morse key is nothing more than an electrical switch, capable of defining two states- on and off! But within that simplicity lies a lot of scope for artistry, ...
G0BSX BSX2 packet radio – Circuit Schematic
G0BSX BSX2 packet radio
Once packet radio started taking off, the limitations of my first foray into AX25 with the "BSX1" TNC became evident. It supported AX25 version 1 only and was l...
Isolated Power Supplies for Telecom Applications – Circuit Schematic
Isolated Power Supplies for Telecom Applications
Using a low-cost high-side precision current monitor to prevent excessive load currents from damaging power supplies.....
Synchronizing Multiple High-Speed Multiplexed DACs for Transmit Applications – Circuit Schematic
Synchronizing Multiple High-Speed Multiplexed DACs for Transmit Applications
This application note provides insight into how synchronize multiple multiplext high-speed DACs in transmitter applications.....
Compact DWDM laser Temperature Control with the MAX8521 – Circuit Schematic
Compact DWDM laser Temperature Control with the MAX8521
Compact thermal control solution for DWDM (Dense Wavelength Division Multiplexing) laser modules can be made using a MAX8520/21 and a single op amp.....
Fitting Extension BT Sockets – Circuit Schematic
Fitting Extension BT Sockets
Extending BT telephone sockets can result in hum appearing on the line or, if two telephone lines are taken through the same cable, cross talk from one line to ...
4 channel data telemetry system – Circuit Schematic
4 channel data telemetry system
4 channel data telemetry system, Electronic Circuits, Schematics, Hobby kits, Custom Electronics design and tutorials homepage. Tons of free working Electronic ...
Black Burst Generator – Circuit Schematic
Black Burst Generator
CMOS analog multiplexers were frequently used at the ETC for various purposes. Here I thought I would present a circuit I borrowed from a Dave Jones design, and...
Telephone Ringer – Circuit Schematic
Telephone Ringer
If you are lucky enough to have a big house, a large garden, and small children, this project just might interest you. It`s actually a telephone ringer capable ...
Telephone Line Indicator – Circuit Schematic
Telephone Line Indicator
With the aid of an (old) moving coil instrument it is very little effort to make a simple voltmeter that, at a glance, indicates the status of a telephone line....