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23

No. Many types of antennas may be unsuitable for transmitting. A so-called active antenna contains an integrated low-noise amplifier (LNA) for amplifying weak signals. (This is very common for GPS antennas.) This amplifier cannot pass a signal in reverse, and could be damaged by transmit power levels appearing on its output. It is possible to have an ...


6

I will answer this question from a "technology of radio" perspective, because half of the question is very much related to the technology of radio. The other half is related to the decoding of a data stream from multiple GPS satellites, and that is beyond the scope of this site. In order to receive the data from the GPS satellites, your best bet would be to ...


5

This is standard NMEA data format. The GPS is configured to provide the following NMEA strings: GPGGA, Essential fix data, time, location, quality of fix, altitude GPGSA, Dilution of precision and active satellites GPRMC, Recommended minimum data: position, velocity, vector, time GPVTG, Velocity and vector You'll notice much of the information is ...


4

Start with a GPS receiver that outputs NMEA data. This data will be made available through a serial connection such as RS-232, USB, or Bluetooth. Pick a serial connection that you can use with your MAC. On the MAC you will need a serial terminal emulation program (not to be confused with the MAC terminal program). A program such as Serial would do the job. ...


3

When you ask if a QRP transmitter could be used to solve your problem, I presume that you mean a low-powered transmitter on HF, meaning roughly 3 – 30 MHz. That would solve the problem of limited range associated with the VHF and higher-frequency bands, but a large antenna would be necessary. The problem is that radio spectrum, especially in the HF ...


3

If you're OK with using a smart phone instead of a regular GPS, you can use: APRSdroid with a Bluetooth TNC for an Android phone PocketPacket with an audio level converter you make yourself with an iOS device.


3

I recommend eliminating the array altogether and instead put a single patch antenna inside the rocket body facing upward. The frequencies of GPS signals will freely penetrate a non-metalic body, nose cone, and parachute. Place any other electronics below the patch antenna so as to not obscure its view of the satellite constellation. A patch antenna in ...


2

It's hard to say whether your active antenna would work properly if provided with 3.3 VDC instead of 5 VDC. I doubt that any damage would be done, but I'm not the engineer that designed the antenna. You might consider adding a boost regulator (and the other parts it requires) to your circuit, which could convert 3.3 VDC to 5 VDC. Here's such a part, ...


2

This question was answered in part at Stack Overflow for an Android device. As they are getting to be quite inexpensive, I assume it will work for your needs. Here are some parts to your solution: Use an OTG cable to connect your phone to your other device. The phone needs to run a program called "ShareGPS ", which will communicate the location over USB. ...


2

Some years ago when electronics on planes were still a big deal, I remember GPS receivers, portable CD players and radio receivers being singled out as Not Allowed. This could be because radio receivers can radiate some of their LO, and this could be at an unwanted frequency and interfere with the aircraft communications or navigation. GPS receivers are no ...


1

If the watch has a GPS, it may also have bluetooth or wifi, and typically the function of the airplane mode is to turn these transmitters off.


1

I understand that the HX-1 Radio Transmitter is an APRS, but how can I receive transmissions from this system? Could I track this with a RTL-SDR dongle? Yes, an RTL-SDR dongle and Direwolf is one good way to receive APRS; there are many others. You can also rely on existing receivers passing data to the APRS-IS. Also, with the NEO-6M GPS how do I receive ...


1

If you are just transmitting GPS coordinates and at a slow rate and need a bandwidth of about 50kbps or less then have a look at LoRa technology. It is low power, low data rate and spread spectrum but it is very reliable with a range over 10km (some as far as 50km) on licence free VHF and UHF bands. It is designed for IoT uses in a noisy environment it could ...


1

On 1) let me take you through a though experiment I created, struggling with the same problem with a ring of antennas fed to make an Omni. You can back it up by calculation later. Antennas are reciprocal devices. Gain in transmit is the same as gain in receive. If you transmit into the bottom port, the corporate feed / matching network works perfectly, ...


1

The only precedent that I can think of for using the ham bands for data beacons, where the data has nothing to do with either ham radio or emergency traffic, is weather station data over APRS. In that case the data is in very short infrequent bursts, and is just being relayed to an internet gateway, rather than being broadcast for general consumption. You ...


1

The first step is to get the file into your computer, either by plugging a USB cable into the radio if that works, or by removing the microSD card from the radio, plugging it into an SD card adapter, and then putting the adapter into your computer. Then copy or move the file. But you probably were asking about how to handle the file. The manual seems ...


1

Forget Baofeng. Buy an old Kenwood THD7 for little more. I have one for 18 years and is rock solid still. It has APRS built-in and many other useful things. You can easily connect it to your PC. take a look at my website: http://www.so6agj.pl/project-gps.php If you need code or hardware instructions please write me a message. 73


1

Disclaimer: I have no experience with any of the below matters; I'm just writing an explanation of what I've heard. Neither your radio nor your GPS unit knows how to encode APRS packets. Therefore you will need to add a device which does, and will also perform the other control/interface functions. In general, a hardware device which encodes and AFSK-...


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