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ARD9800 DIGITAL COMMUNICATIONS MODEM FAQ Q: WHY DO I WANT DIGITAL VOICE COMMUNICATIONS? A: HF SSB is OK but it has its limitations. The ARD9800 Digital Voice System can dramatically improve your HF communications. 1. The ARD9800 provides NEAR FM QUALITY audio using SSB. 2. The digital signals may require LESS SIGNAL than analog throughput making operations possible under adverse band conditions. Q: MUST I MODIFY MY HF TRANSCEIVER? A: No! Changes to your rig are not needed. All you have to do is solder the connector to the cable for the mic input to your transceiver. A cable and 8-pin round mic connector are provided with the ARD9800. (Optionally, you may also purchase a pre-made cable for most popular transceivers.) It's basically "plug & play." The ARD9800 system uses digital tones confined to the normal voice audio spectrum. That means your transceiver should pass the digital signals as it would any normal voice communication. When you transmit normal SSB signals, your operations are the same as always. To transmit digital signals, you simply select the digital mode using a front panel switch on the ARD9800. Q: IS IT DIFFICULT TO CONNECT? A: No! If you have connected an external modem to a computer or a packet terminal node controller to a ham radio, the process is similar. There are two simple connections to your transceiver. 1. To the mic input jack of your transceiver. 2. From the "speaker out" connection of your transceiver to the "speaker in" jack of the ARD9800. That's it! 3. The only other connection is to a 12VDC power source. Q: WHAT DO I NEED TO CONNECT? A: You must build or buy a cable that matches the microphone-input pins on your transceiver. Second, you simply connect the provided cable between your transceiver's "speaker out" port and the "speaker in" port of the ARD9800. Finally, you must connect the ARD9800 to a 12 VDC power source. As optional enhancements, you can connect an external station speaker to the ARD9800, you may use the provided serial-port interface cable to connect the ARD9800 to your computer and if you have purchased the optional memory expansion module, you can transmit and receive images using the video in/out ports. Q: HOW DO I KNOW THE PROPER CONNECTIONS FOR MY RIG'S MIC INPUT? A: Most transceivers have the pinouts for their microphone connections shown in their respective operator's manuals. Sometimes they are listed under packet radio connections. You can also check your radio manufacturer's web site or other ham radio web sites. (AOR urges you to be sure the information is accurate before you proceed.) Q: HOW DO I SET MY TRANSCEIVER FOR DIGITAL OPERATIONS? A: Very few changes are needed. You should not use the "Noise Blanker" or have any "Narrow" band pass filters activated. Turn off any Digital Signal Processing (DSP) devices. Turn off the speech processor. After installing the ARD9800, be sure to check your audio output levels (the ALC meter is one method). You may need to adjust your transceiver's mic gain, and/or the output of the ARD9800 to obtain the best setting. Q: CAN I STILL USE MY EXISTING MICROPHONE AND EXTERNAL STATION SPEAKER? A: Yes. You may have to make an adapter for the pinouts of your mic to match the ARD9800's input, or resolder the pin connections on your mic's cable, but that's all. The ARD9800 comes with a mic, so you may not want to change your mic at all. The ARD9800 has a "speaker out" jack for use with an external station speaker. Note that the ARD9800 also has an internal speaker and a volume control. Q: DO I GIVE UP USING MY TRANSCEIVER FOR ANALOG COMMUNICATIONS? A: No! You retain the normal ability to use your transceiver as you have in the past. The ARD9800 adds digital communications to your abilities. In fact, the ARD9800 lets normal analog communications pass through, but automatically recognizes digital communications from another ARD9800 unit. Q: DO I HAVE TO CONSTANTLY ADJUST THE TRANSCEIVER WHILE USING THE ARD9800? A: No. The ARD9800 uses a protocol that accounts for a reasonable amount of drift during the contact. Q: SHOULD I WAIT FOR ONE OF THE MANUFACTURERS TO DEVELOP A DIGITAL SYSTEM? A: The ARD9800 system is here today! Best of all, it can be used with ANY transceiver, so you're not captive to just one manufacturer's digital platform. Q: IS IT LEGAL? A: The ARD9800 uses an open published digital protocol (G4GUO) per FCC rules. Think of the ARD9800 as a "wireless modem" similar to a Terminal Node Controller, (TNC) like a packet radio unit that's capable of RTTY, AMTOR, etc. Those units use open, published protocols as well. ARD9800 transmissions use the normal audio pass band, so they are similar in bandwidth characteristics to a normal analog SSB voice signal. Q: DOES IT WORK IN OTHER MODES? A: Yes! The ARD9800 can be used in AM or FM modes, however, FM mobile operation could be prone to "picket fencing" which might result in the loss of data. Also, repeater "key-up" time could delay the passing of the ARD9800 digital "header" causing a loss of data. As such, AOR cannot make any warranty as to the dependability of the digital mode in every given situation. (Just as any manufacturer cannot warrant what band conditions will be at any given time.) Q: WILL OTHER HAMS USE THE ARD9800? A: The ARD9800 prototype was demonstrated for Ham audiences at Dayton, Ohio and Friedrichshafen, Germany. HAMS LOVED IT! Most asked question was, "When is it available?" Q: WILL I HAVE TO OPERATE DIFFERENTLY? A: Not really. We suggest that "CQ" calls in digital mode be kept short because a "digital header" is sent at the start of each transmission. This header allows other ARD9800 units to "lock on" to the digital transmission. Likewise, we suggest a pause of about 1 second at the beginning of each transmission to allow the header to clear. You might also consider calling "CQ Digital" in the analog SSB mode. A digital response from another AR9800 user will be automatically recognized by your unit. Q: CAN I ONLY TALK WITH ONE USER AT A TIME? A: NO! You can speak with as many similarly-equipped operators as you wish. The ARD9800 uses an FEC protocol that does not require acknowledgement. Therefore, you can communicate "one to one" or in a "round table" just as you do using SSB today. Q: MUST I SWITCH BETWEEN DIGITAL AND ANALOG COMMUNICATIONS? A: The ARD9800 automatically recognizes digital transmissions from other ARD9800 units. You can select transmitting in digital or analog modes using the front panel switch on the ARD9800. Q: WHAT DO OTHER OPERATORS (NOT EQUIPPED WITH ARD9800) HEAR? A: Analog operators will hear the header tones at the beginning of each transmission and then a "buzzing" sound as the digital transmission continues. Q: WHAT DOES THE DECODED DIGITAL TRANSMISSION SOUND LIKE? A: It's been described as "near FM" in its quality. It's quite remarkable and one of the big advantages of using the ARD9800. Q: HOW MUST I IDENTIFY MY STATION? A: Check the rules that apply in your individual country. In the USA, it is acceptable to identify in the mode you are using, in this case, digital. You may also augment your ID using Morse tones or analog SSB. Q: WHAT ELSE DOES IT DO? A: With the optional memory board, images can be easily transferred, similar to SSTV but we believe the ARD9800 sends a higher quality image. You can also send file transfers. The ARD9800 has ports for composite video input and output. That means you can easily send an image captured from a video camera or digital camera that has a normal NTSC "video out" jack. Likewise, you can display and/or save received images on a monitor or storage device that uses a normal composite NTSC video input. Q: CAN ARD9800 SIGNALS BE ENCRYPTED? A: NO! That would not be acceptable on the Amateur Radio Bands. The G4GUO protocol is an open, published format that has been adopted for digital voice communications by AOR. It is not a form of encryption and there is no ability to activate encryption in the ARD9800. AOR offers a commercial version called the ARD9900 which is intended for commercial users only on commercial bands. Encryption is a feature available on the ARD9900. Q: HOW AND WHEN CAN I PURCHASE THE ARD9800? A: The ARD9800 is now available through AOR dealers. Q: WHAT IS INCLUDED WITH THE ARD9800? A: You get: 1. ARD9800 Modem unit 2. Power cable for connection to 12 VDC 3. Speaker connection cable (from speaker out on your rig to ARD9800 rear panel) 4. Mic Input cable (from rear panel of ARD9800 to mic input jack of your rig) 5. 8 pin circular mic input connector (requires soldering for your rig's input scheme) 6. Microphone for connection to front of ARD9800 7. Computer cable (from rear of ARD9800 to serial port of your computer) 8. Operator's manual. Q: WHAT DOES IT COST? A: MSRP is $549.00 USD. Individual dealer prices may vary and are often lower than MSRP. And remember, the ARD9800 adds an entirely new mode to your existing transceiver. Q: ARE THERE ACCESSORIES I CAN PURCHASE FOR THE ARD9800? A: 1. 12VDC Power cube 2. Memory module VM9800 (needed for sending/receiving images). 3. Pre-made microphone jack input cables for most popular transceivers. Q: WHAT MAY I USE TO PROVIDE POWER TO THE ARD9800? A: AOR recommends the use of a 12 VDC regulated power supply or a 12 VDC battery. Try to avoid using "wall cube" supplies or power sources that may have "ripple." Q: WHAT OTHER TIPS CAN YOU PROVIDE? A: Use quality shielded microphone cable for the connection between the ARD9800 and your transceiver, or buy a "packet" interface cable from your transceiver's manufacturer. Also, Adonis microphone matching cables are an exact match to the pinouts of the ARD9800 to the microphone inputs of most modern transceivers. Be sure your ARD9800 is well grounded so as to avoid stray RF problems. Q: MY POWER OUTPUT METER STAYS IN THE SAME PLACE WHEN I TRANSMIT, EVEN THOUGHT I AM USING SSB. IS THAT NORMAL? A: Yes. The ARD9800 transmits using 36 PSK subcarriers. The waveform looks almost like an FM signal. As a result, you may be able to transmit and receive extremely high quality digital audio using considerably less output power than that of an analog SSB conversation. Those who have used PSK31 already know that not much power is necessary for a contact in that mode. If you are concerned about your transceiver's duty cycle, cut the power output. |