Remote control systems are hardly new but before you write this one off as just another variation, take a look at the features panel. It's got a lot more features than other standard "run of the mill" remote control projects.
Among other things, these features include a 4-digit combination lock to prevent unauthorised use, extra long range (up to 1.5km), 16 independent channels and programmable channel functions. There are also two modes of operation: Mode 1 and Mode 2.
Two pre-built UHF modules make this unit really easy to build. The transmitter module is designated the TX434 and uses a SAW resonator to lock the transmission frequency to 433.92MHz.
This module is truly tiny, measuring just 20mm long x 8mm wide. It has a data rate of 1200pbs (maximum), a frequency tolerance of 175kHz and operates from a 3-9V DC supply. It also has seven external connections and is installed "surface-mount" style on the back of the transmitter PC board.
At the other end of the link is the complementary RX434 UHF receiver module. This is a full superheterodyne UHF receiver that measures just 44 x 15mm. It is crystal-locked to 433.92MHz, has a sensitivity of 115dBm, operates from a 5V DC supply and has eight external connections (four at either end) which are brought
out to pin headers. It is installed directly on the receiver PC board.
Both UHF modules are supplied pre-aligned, which means that you don't have to make any adjustments after assembly.
- 6 channels - see text for channel functions.
- Up to 1.5km range or further in some cases.
- 4-digit combination lock with fully reprogrammable code.
- Two modes of operation - full featured or standard toggle/momentary.
- Back up fail-safe code in case user code is lost or forgotten.
- Fail-safe code is different for each kit sold.
- Program boots up in "Locked" mode - system unusable if stolen.
- All codes, times and modes stored in EEPROM and reloaded at power on.