There are a few modes that sacrifice radio efficiency in exchange for simplicity, such as APRS, however APRS has much shorter transmit durations than PSK31 allowing for the frequency to be shared (I've seen operators with an active PSK31 signal for over a minute, imagine the APRS pileup if every station in range was forced to wait that long for an open carrier).
Ic 7800 remote on android software#
If you want to use digital in VHF/UHF, you need either an SSB transceiver (might be available for 2 meters?) or a digital radio (using D-STAR, TRBO, or something else) or an SDR (a software defined radio may allow the necessary types of operation). The properties of FM do not allow for use of digital modes in the same way as SSB does. You would effectively be taking up an entire FM channel but only using less than one percent of it. You couldn't use something like fldigi to receive multiple PSK31 signals in the same FM channel at once, because your FM receiver is physically incapable of receiving and demodulating more than one signal at a time. In FM, every input signal uses up the entire channel width. In SSB, the bandwidth actually occupied by the output signal is equal to the bandwith occupied by the input signal - so if your input audio shifts by 31.25Hz, your output RF shifts by 31.25Hz. That is not the same as the SSB that is used in HF transceivers for digital mode operation - it's a completely different kind of modulation. FM transmits a carrier at a single frequency that is modulated. If it isn't through the front microphone connector, it's through an accessory connector, which is available on every commercial radio I'm aware of - although perhaps only on a few amateur mobiles.īut why would you want to? SSTV and PSK31 cannot be reasonably transmitted over FM.
Ic 7800 remote on android Patch#
Sure, most radios have the ability to patch in audio. I also often use the "data" connector of my FT-7800 for recording received voice communications on a computer. IARU Region 1 (Europe) SSTV(FM/AFSK) frequency for 70 cm is currently 433.400. Some US web sites cite VHF/UHF SSTV AFSK FM calling frequencies. SSTV isn't so narrow (about 3 kHz), and there have been more or less official FM channel allocations for it. A lot of amateur FM voice communications don't have a lot of useful information content, either. Then again, it might be fun, and if you live in an area where most of 70cm is almost completely quiet and inactive (like I do), a little inefficiency on an irregular basis is not going to do harm, if you're having fun. PSK31 over FM in particular is quite strange and unusual, since PSK31 is designed to be a very narrow-bandwidth (31.25 Hz) mode for SSB transceivers, and transmitting it over FM (some 20 KHz) would be a waste of perfectly good radio spectrum and transmitter power. Most of SSTV and PSK31 activity is on HF SSB, although VHF/UHF digital chat as such should be a lot of fun. But it's not overly popular in most areas, so you might have to talk some friends to play with it. Technically, you can run SSTV or PSK31 over FM, and that "data" connector will suit that purpose perfectly. The "9600" pin audio output is taken before audio filter/amplifier stages of the radio, and has a flatter audio frequency response that is good for high speed data such as 9600 bit/s packet or AIS reception. I quoted the bit rates, since the radio documentation often cites these standard packet radio speeds, although in reality it's just audio, and the radio doesn't really care about any bit rates as such. RX audio out, "9600 bit/s" discriminator output.RX audio out, "1200 bit/s" "normal audio".
The 6-pin data connector is originally designed for attaching packet radio TNCs and other data equipment, and usually has at least the following pins:
Currently manufactured dual-band examples include Yaesu FT-7900, Kenwood TM-V71, Icom IC-208H - they all have the same 6-pin mini-DIN "data" connector using the same main pinout. Most modern VHF/UHF FM mobile rigs designed for Amateur Radio use have a "data" connector on the back.
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