Participate on the D-Star or DMR network with a radio, only with a USB Vocoder!
All digital modes in ham radio require a voice codec (coder/decoder aka vocoder (voice codec)). The purpose of a codec is the transformation of voice into a digital data stream and vice versa, from digital information to analogue voice. During this transformation much happens inside the codec than just an analog/digital conversion. The goal is to reduce the data rate as muich as possible, because this will require less bandwidth in the limited radio spectrum. This is achieved by reducing and compressing voice in various ways, on the analog and digital side. These procedures are quite elaborate and hard to develop and therefore protected by patents. The developer then pours her ideas in a hardware chip and sells this to manufacturers of radios and other devices.
Since the digital ham radio systems borrow technology from commercial systems, also the codec definitions have been adopted. Although there are free open source codecs out there (free as in free speech, not as in free beer), these free codecs are not compatible with commercial systems because they use others procedures. So we have to live in ham radio with these existing commercial codecs. Every digital radio for D-Star, DMR, P25, C4FM, NXDN etc contains such a codec chip, you buy it with the radio. Now, if you want to participate with using an actual radio, you still need such a codec chip to transform the digital data. This is exactly what the DVMEGA DVstick-30 does.
The DVMEGA DVstick-30 contains a codec by the manufacturer DVSI, the AMBE-3000©. This is a state-of-the-art codec chip, which supportes various encoding systems. The result is that you can use the DVstick-30 with suitable software with different systems like DMR or D-Star, in the furure maybe als owith other systems as software deveops.
A suitable software for use with the DVstick-30 is Blue DV by PA7LIM. This software is available for a lot of platforms like Windows, some IOS versions (Ipad, Iphone) and Linux, and with suitable hardware (OTG capable) even on Android and IOS. You further need a headset or microphne and speaker for your computer, or you use the built in mic/speaker of your notebook. PTT keying is done through a button of the software. Another software is OpenDV by DL5DI, but this requires more work like compiling the software yourself.
The benefit of such a 'radio less' application in ham radio is the possibility to stay in touch with the friends at home when you are traveling without a radio, or wehen no suitable digital repeaters are nearby. The requirements for the internat data rate are - thanks to the capable codec chip - quite low, usually an ISDN line with 64 kbps is absolutely sufficient.
- USB 2.0 Full Speed Interface
- UART baudrate 28k8 - 460k8
- Data rates adjustable from 2k0 to 9k6
- AMBE-3000 full-duplex AMBE+2™ Vocoder chip by DVSI
- Compatible with BlueDV, AMBE-Server, Dummy Repeater(Open DV) and others