The hardware required to add video to digital voice
Hardware Setup for FreeDV plus Video
Connect the hardware as shown in the diagram below. See the "Software" page for the software required to run FreeDV plus Video.Setup for FreeDV plus Video
HF Transceiver:The bandwidth for FreeDV+ is 3.5 kHz, so make sure that your transceiver's TX and RX bandwidths can be adjusted accordingly. Another requirement is that the IMD3 must be better than -40 dB for the transmitted signal, requiring either Class-A outputs (some Yaesu transceivers) or adaptive predistortion (soon to be available with Flex Radio transceivers; or use an Apache Labs transceiver with PureSignal). WA6NUT uses PureSignal with an Apache Labs ANAN-10E SDR and an Ameritron AL-811 amplifier. See the link below for information on the ANAN-10E. For more information on adaptive predistortion, see the "PureSignal" and "Technical" pages (links at the top of this page).
In the unlikely event that your ANAN-10E PowerSDR software crashes with a "Fatal Error" message, recovery is possible following the procedure given in the "Fatal Error Recovery" link below.
ANAN-10E Link - - Fatal Error Recovery Link
Sound Card Interface: For about $100 USD you can purchase a USB sound card interface, such as the MFJ-1204 or SignaLink™ USB. An advantage of using a USB sound card interface is that it incorporates a USB sound card, so no additional sound card (see below) is required. But the VOX feature ("PTT Detector" for the MFJ-1204, "Auto-PTT™" for the SignaLink™ USB) must be bypassed for FreeDV+, because the video TX app generates a continuous TX audio waveform, regardless of PTT status. See the link below for a PDF document describing how to modify the MFJ-1204 for FreeDV+.
MFJ-1204 Mods Link
USB-to-Serial Cable: Required if the sound card interface uses a serial port for TX/RX (PTT) control, and if the PC has no serial port. The cable connects between the sound card interface and the PC or hub USB port for TX/RX (PTT) control. The author has used a Gigaware cable (Radio Shack P/N 26-949) with good results. Many amateurs report better performance with USB-to-Serial cables using the FTDI chipset (instead of the Prolific chipset).
USB Hub: A USB hub is not required if the PC has 3 or more USB ports. The author has used an Amazon Basics BOODQFGJR4 USB hub with good results.
Amplified Speakers: The author uses amplified speakers similar to Cyber Acoustics CA-2014RB speakers
Camera/Mic: The author uses a Logitech C920.
Laptop PC: When a higher-performance PC is available, the Video TX, FreeDV, and Video RX software are installed on the same PC. The author uses an HP 17z-cp200 laptop running Windows 11.
- 5 July 2013 -Back to WA6NUT home page
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