elsey.jack
New Member
Hi everyone,
I am working on a weather balloon as a research project over the summer. I need to get temperature measurements up to a height of 100 M.
I am using a 434 MHz RF transmitter and a 434 MHz RF receiver to transmit the data between the balloon and a hand-held display unit.
I am using a picaxe microcontroller in the balloon unit and another in the display unit. I am reading the temperature using a thermistor with the method discussed here.
The maximum range of the transmitter is 500 ft. The range is dependent on its supply voltage (2 to 12 V). My breadboard prototype worked perfectly when I had the transmitter powered at 5 V.
I have assembled the circuit on protoboard and am powering the transmitter with 11.2 volts from a three cell lipo battery. Now, however, the transmitter is starting to heat up the entire circuit through its connecting wires, falsely raising my temperature readings!
The data sheet (pdf) for the receiver unit recommends a 17 cm long wire for the antenna. If I improve the antenna can I get a longer range? Do you think that I could get 100 M range if the transmitter was powered with 5V?
I am working on a weather balloon as a research project over the summer. I need to get temperature measurements up to a height of 100 M.
I am using a 434 MHz RF transmitter and a 434 MHz RF receiver to transmit the data between the balloon and a hand-held display unit.
I am using a picaxe microcontroller in the balloon unit and another in the display unit. I am reading the temperature using a thermistor with the method discussed here.
The maximum range of the transmitter is 500 ft. The range is dependent on its supply voltage (2 to 12 V). My breadboard prototype worked perfectly when I had the transmitter powered at 5 V.
I have assembled the circuit on protoboard and am powering the transmitter with 11.2 volts from a three cell lipo battery. Now, however, the transmitter is starting to heat up the entire circuit through its connecting wires, falsely raising my temperature readings!
The data sheet (pdf) for the receiver unit recommends a 17 cm long wire for the antenna. If I improve the antenna can I get a longer range? Do you think that I could get 100 M range if the transmitter was powered with 5V?