I am a little confused with D star?

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When using d star are you still transmitting in FM and AM modes? Second question with a standard dongle or other types of dongles (not a d star dongle) can you receive and transmit d star.
 

902

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When using d star are you still transmitting in FM and AM modes? Second question with a standard dongle or other types of dongles (not a d star dongle) can you receive and transmit d star.
I'll take the first part. You are transmitting in C4FM (very similar to P25, but not the same protocol or vocoding or data rate), a 4-level direct frequency shift keying transmitting data at 1.2 kbps. It occupies a 6.25 kHz channelspace and is very similar to (but still different) NXDN. It's FDMA, so it is FM, but nothing you can hear without a compatible decoder.

I don't know anything about dongles, someone else will need to field that.
 

n5ims

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Reguarding the DStar dongle, check out this FAQ for your answer(s) http://www.k6mdd.org/images/DV_Dongle_FAQ.pdf

What is it?

When a DV Dongle is connected to a PC or Mac and used with DVTool software, an amateur radio operator can connect to the international D-Star gateway network and receive/transmit just like a D-Star radio user.
Please read the answer closely however since the term "receive/transmit" may not be exactly what you're thinking when you picture it. The phrase "connect to the international D-Star gateway network" is probably the key to this answer. You don't directly use a radio with a dongle, but you talk through a D-Star Gateway's radio over the internet from your computer to actually transmit over the air. This gateway may be local so you can talk to folks nearby, but it also can be thousands of miles away.
 

VK5ZEA

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D-Star uses GMSK modulation at 4800bps. The D-Star spec allows for GMSK, QPSK and 4FSK, but only GMSK has been implemented at this stage. GMSK is an "older" modulation system, but this also means that it's a lot easier for those wishing to home-brew D-Star modems.

The DV Dongle is commonly used to allow you to talk to D-Star repeaters and reflectors from your computer (PC, Mac, Linux). It contains the AMBE vocoder that D-Star uses.

The DV Dongle also allows you to be a little adventurous and use it to transmit and receive D-Star on RF with a suitable modem (either hardware or sound card based) and a radio with a 9600 baud packet socket. You can "roll your own" D-Star radio if you so desire... maybe not as elegant as a commercial D-Star radio but it does work.

Michael.
VK5ZEA
 
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