MICRO-TRAK 300 MANUAL VER 1.4 The Micro-Trak 300 Version 1.4 is a miniature APRS (Automatic Position Reporting System) transmitter operating on the North American APRS frequency standard of 144.390 MHz. and is also available on the European standard frequency of 144.800 MHz. The transmitter is a motherboard and accepts a TinyTrak3 compatible DIP PIC. The entire assembly is only 1 X 3.3 inches, and weighs less than one ounce! The Micro- Trak 300 is a creation of VHS Products, and is distributed exclusively by Byonics. The MT-300 Version 1.4 has many significant improvements over Version 1.4, including an integral SMA antenna mounting point, and on- Board GPS and PTT status LED s. The MT-300 is extremely compact and light, due in part to the enclosed RF section. Because a shielded, premanufactured RF module is used in the kit, assembly consists of installing a few parts, simple programming, and providing power and a GPS input. No tuning or adjustments are required. Most electronic hobbyists can complete the assembly within half an hour. Because of its small size and light weight, the MT-300 Version 1.4 is ideal for portable and airborne operations. Small size not withstanding, the Micro-Trak 300 has a power output in the range of 300 mw, and is capable of operating at extremely long ranges. An on-board 5 volt regulator provides an optional 200 MA, power output for your GPS receiver. (Many applications, including the use of the device with hand-held GPS units, will not require the 5 volt output of the Micro-Track.) The entire system runs well on 9-15 volts DC, and draws only about 10 milliamps in standby, and increases to 180 milliamps during transmissions (which last approximately 1/3 of a second using MIC-E) This provides for a very efficient battery-powered package. The transmitter will typically run for about 25 hours on a nine-volt battery with 2 minute check-ins. No case or package is provided with the Micro-Trak 300, allowing the user to package the device according to their unique needs. The design philosophy called for as small, light and basic a package as possible. The programming and GPS input connection is set up to use a DB9 Male connector (The same as a standard TinyTrak 3) by simply sliding the connector over the tabs. You may choose to solder your GPS or programming cables to the board connections to minimize the weight and size of the device. The Micro-Trak can connect to a standard GPS receiver directly through the DB9 connector, but it is important to remember that computer programming and communication uses a reversed connection, meaning you will need a female to female Null modem cable, or a null modem adaptor and a gender-changer connector for programming your Micro-Trak. These cables and/or connectors are available from Byonics. The combination of the Micro-Trak 300 and the TinyTrak 3 PIC produces a hybrid that is capable of being adapted to virtually any portable APRS project. It is important to remember, that this is a transmit-only system, and may transmit coincidentally with other APRS transmitters. Complete information about TinyTrak and the Micro-Trak 300, Version 1.4, as well as configuration software may be found at: http://www.byonics.com/microtrak300.e-mail information requests about the Micro-Trak 300 can be addressed to: microtrak300@byonics.com
PARTS Printed Circuit Board TinyTrak 3 PIC Integrated circuit DPAK 5 volt surface mount voltage regulator T1 LED Red- Transmit T1 LED Green- GPS RF Module 10 MFD surface mount capacitor 10 MHZ resonator 1K Resistor (3) (Brown, Black, Red) 2K Resistor (Red, Black, Red) 3.9K Resistor (Orange, White, Red) 8.2K Resistor (Gray, Red, Red) 10K Resistor (Brown Black Orange) 18 PIN IC Socket SMA connector Assembly And Operation The Micro-Trak 300 is provided as an unassembled printed circuit board. The final assembly is left to you to accommodate your particular needs. Only a few connections must be completed.
Assembly Begin assembly by installing the seven 1/8 watt resistors on the top side of the PC board. You will see that the values are marked on the board. (See photo) Install and solder in the 18 pin IC socket. By convention, the end of the socket with the U shaped indentation is the top, and should be installed pointing towards the RF module. Install the LED s taking care to verify orientation. (Note flat sides) You may cut the 1K resistors going to one or both LED s to conserve power if required. There are two devices mounted on the bottom surface of the board, a DPAK 5 volt regulator and a 10 MFD surface mount capacitor. The best way to install these is to use your soldering iron to tin one pad and tack the components in place. When you have the component positioned as shown in the photograph, solder the other pins down. It is very important to make sure that you solder the case connection of the DPAK 5 volt regulator to its respective pad. Capacitor polarity is critical. The thick line on the capacitor should be pointing towards the voltage regulator. There is a + marked on the board. Solder in the 3 pin, 10 MHz resonator. Orientation does not matter. Install the RF Module by bending its leads 90 degrees to the case, and inserting it into the marked position on the PC board. Solder all seven pins on the bottom of the board. You can secure the module to the PC board by soldering the case to the surface mount pad for extra stability, but be careful not to overheat the RF module. It helps to pre-tin the large surface mount square pad, and to make sure that the RF module case is clean before you try to apply solder. Connect your power input wires as shown in the photo and the PCB layout shown below. Install the TinyTrak PIC by bending its leads against a flat surface so that they are perpendicular to the IC body. Note the orientation of the chip in the socket: the end with the indented dot should be installed facing the RF module. Carefully press the chip into the socket, making sure no leads have drifted out of alignment.
Micro-Trak 300 Serial Connections 1 2 3 4 5 TOP SURFACE DB9 CONNECTIONS Pin 1 Pin 2 Pin 3 Pin 4 Pin 5 No connection Serial Data In (GPS and programming) Serial Data Out + 5 Regulated output (optional for GPS power) Ground
Auxiliary Connections Note that there are solder pads connected to pins 10,11,12,13, and 17 on the PIC. The connection on pin 12 (marked sw ) is used to switch the TT3 Configuration (refer to the TT3 manual) pin 13 (marked en on the board) is for a logic level switched power output. This may be used to control external devices using the Power Enable feature in the Byonics configuration program. The use of these pins is optional, and not required for regular operations. Refer to the TinyTrak 3 manual for further details. Operation and Programming The Micro-Trak may be connected to a computer for programming by sliding a DB-9 male serial connector over the card edge connector on the bottom edge of the board. The DB-9 connector may be permanently installed by soldering the connector to the card edge connections. Note that you will require a Null Modem and gender changer adaptor to program your Micro-Trak. Consult the TinyTrak 3 manual for instructions on using the Byonics configuration software to program the TT3 PIC on-board the Micro-Trak. Be aware that the Micro-Trak is a transmit-only device, and will transmit over other stations. It is not a good practice to send position reports too frequently, since this can jam other stations, and will use Micro-Trak battery power too quickly. 120 second checks-ins are recommended. Power Input Note the two small pads on the lower right hand corner of the PC Board. Just below the letters en you will see a small + mark. This is the DC power input line. The ground input is directly below that. Not that all four corner mounting holes are electrically connected to ground as well. Antenna Connection The printed circuit board is pre-drilled for an included SMA connector. A wire antenna or coaxial cable may be soldered to the antenna output for weight or space saving requirements. Uninstalled Components You may note that there is a SOT-3 component location on the bottom of the board. This is for an optional Microprocessor reset module that is not utilized in normal operations, and may be ignored. Thank you very much for your purchase of the Micro-Trak 300, Version 1.4. VHS and Byonics wish you many happy hours of APRS operation. You are invited to offer your comments and recommendations.
MICRO-TRAK DATA SPECIFICATIONS The MICRO-TRAK 300 is a narrow band radio transmitter for use in long range data transfer applications. Applications Tracing and asset tracking systems Packetized data transmissions Telemetry and telecommand Data loggers In-building monitoring and control DGPS systems. Weather Stations Technical Summary Transmit power: 300mW (24.7dBm) nominal Operating frequency: 144.390 MHZ, or 144.800 MHZ Supply range: 9-15 VDC Current consumption: 180mA nominal transmit Data rate: 300, 1200 Baud AFSK PCB Dimensions 1 X 3.3 Inches Weight < 1 ounce Performance specifications Absolute maximum ratings Operating temperature: -10 C to +60 C Storage temperature: -30 C to +70 C Electronic Characteristics DC supply TX Supply current RF Power Output Spurious emissions FM Deviation RF Center Frequency Modulation bandwidth @ -3dB TX select to full RF 9-15 VDC 180 ma +25.7 dbm (max) -40 dbm 3.5 khz (Peak) 144.390 /144.800 MHZ 3 KHz <5 ms