| Tracksoar | Byonics Micro-Trak RTG | SainSonic AP510 | BigRedBee | |
|---|---|---|---|---|
 |  |  |  |
|
| Size (without battery holder) | 2" long 3/4" wide 1/2" thick | 3.5" long 1" wide 1/2" thick (estimated) | 9" long 3.1" wide 1.1" thick | 3.3" long 1.3" wide 1/2" thick (esitmated) |
| Weight (with batteries and holder) | under 2 ounces (with battery holder and batteries) | unknown | 100 grams without case | 136 grams w/ 5x AAs |
| Open Source | Yes | No | No | No |
| Add additional sensors | Yes GPIO/I2C/SPI | No | No | |
| Sensors Included | Yes Temperature Pressure Humidity | N/A | Temperature | N/A |
| Frequencies | 144 MHz 120 - 180 mhz and 434 mhz (avilable with pin compatible transmitters) | 144 - 148 MHz | Frequency Agile (136 - 175 MHz) | Frequency Agile (144 - 148 MHz) and 434 MHz |
| Transmit Power | 300mW | 10W | 1W | 1 - 5 W |
| power source | 1.2 - 5 volts 2 X AA lithium ion batteries | 9 - 15 volts 9 volt lithium battery | rechargeable 3300 mah lithium battery | 5 x AA |
| Battery Life (at 1 minute transmit interval) | 12 hours at 32F (based on 2 AA lithium batteries) | 6 hours (estimated based on a lithium 9v battery) | 24 Hours (at 1 minute transmit interval) | 48 hours (at 1 minute transmit interval) |
| Price | $200 | $220 | $99 | $265 |
| Website | tracksoar.com | byonics.com | http://www.sainsonic.com/ | bigredbee.com |
here is an in depth review by an independent weather balloon enthusiast:
http://bear.sbszoo.com/construction/traker/Tracksoar/V1-1.htm
300MW? I’m assuming that should be mW…. Then on the other hand you have 144mhz. milli Hertz? The H should be capitalised so MHz? Get the units right if you want anyone to trust you in a technical world.
I would be wanting a 144.800MHz version… what frequencies will you be going into production with?
Yes you are correct, I have fixed the abbreviations.
I am only shipping the 144.390MHz transmitter for the initial run. I am selling an assembled version without the transmitter so international users can purchase the correct Radiometrix module for their country. I am working on a post detailing which module should be purchased for each country to make this process more straight forward.
Here are a few updates from an active flyer of AP510 and Bee:
AP510
weight 100g (3.5oz) without heavy metal case. Frequencies 136-175MHz Battery life ~24 hours (at 1min transmit). On-board data storage.
BigRedBee 2m
weight 136g (4.8oz) w/ 5x lithium AA. Battery life ~48 hours (at 1min transmit and 5x AA). On-board data storage
Thanks Paul, I’ll add this to the comparison chart.
A couple of questions:
1. What is the shortest time period for transmitting each packet? I’m looking at 20 second intervals for some short term applications in unpopulated areas. I assume it is programmable.
2. Are the sensors fixed on board or extendable to outside the module? That is, if the board is open to the elements, then the readings may not be exactly correct.
3. Relating to question 2. If the board is open to the elements, what is the lowest operating temperature? Assume the batteries are insulated.
Hi Robert, those are good questions!
1. 10 second intervals is the absolute fastest you can poll the sensors and transmit. The transmit interval is indeed programmable, it can be found in the config.h file in the firmware. If you wish to transmit that often I would adjust the APRS settings (also in config.h) to prevent overloading the APRS network.
2. The included sensors are fixed on the board, however adding new sensors is very easy using the included headers that breakout i2c / SPI / GPIO. The temperature and humidity readings will likely differ from outside your payload enclosure.
3. Lowest operating temperature is -40C, at that temperature the GPS antenna will detune and cause a loss of position data until it warms up again. Next to go is the batteries at -100C (assuming you are using 2x L91 Energizer Lithium batteries), I don’t have the resources to test below that temperature.
Please let me know if you have any further questions.
Hi, I recently bought a tracksoar.
Is it possible to turn the transmit power down through programming?
Also, how long would one L92 last?
Or you could tell me current draw @1.5v, or you could tell me power consumption in watts. Not sure what your voltage booster/regulator’s efficiency curve looks like.
From what I calculated, 2x L91s in series is 9 watt-hours, which means that the power consumption is 0.75 watt, or a staggering 250mA!?
Thanks,
Saad
Hi Saad, Unfortunately the transmit power is not adjustable through software, or hardware means.
I will have to re-test the current draw with 1x AA as I no longer have my results from my R&D. You can find the datasheet for the LTC part here: http://cds.linear.com/docs/en/datasheet/3426fa.pdf
The power draw peaks at about 1 amp during transmit but averages around 70ma during idle. There are a number of tricks that could be implemented to drop the power consumption but have not been for ease of use.
Please let me know if you have any further questions.