NPARC - EchoLink SysOp Mode

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New Providence Amateur Radio Club
The Radio Club of the Watchung Hills Area

EchoLink SysOp Mode

by KC2RLM

	The Equipment
	SysOp Program Settings

The information on this page might be helpful to anyone who plans to make their station an internet-to-radio link -- what EchoLink calls SysOp Mode. When in SysOp mode, anything received from an EchoLink internet station is transmitted on your radio; likewise, any transmissions heard by your radio will be relayed on the internet stream to a connected EchoLink station.

Before running in SysOp mode, run EchoLink in the default "Single User" mode for a while, so that you gain a basic familiarity with EchoLink. When you're ready to try SysOp mode, first read the EchoLink Help including:

	Getting Started: Modes
	Getting Started: Interfacing
	Configuration: Sysop Settings
	Troubleshooting: Sound Card Adjustments

The Equipment

For SysOp mode you'll need the following:

An internet connection that can run the entire time you plan to operate as a link. Even a dial-up connection should work, although this may not be fast enough to support EchoLink's optional "conference" mode (see EchoLink Help for info about "Conferencing", i.e. multiple station connect to you).

A two meter base station radio, ideally with high power of at least 35-50 watts. The better the antenna location and the higher the power, the better the signal and the wider the area of coverage. (Actually you could hook up a radio on any band!)

A computer running Windows 95 or higher

The EchoLink program -- the same version is used for both single user and sys op modes.

A 16 or 32 bit computer sound card. Most recent vintage computers (last 6 years) come with such cards and most cards should work with EchoLink. The earliest 8 bit cards may not.

A sound card interface to connect the radio to EchoLink via the computer's sound card. An example would be the RASCAL sound card interface, a kit we built at NPARC club meetings in 2002. You can also build your own interface (see http://www.qsl.net/soundcardpacket/cablestart.htm for advice) or use a commercial interface, such as West Mountain's RigBlaster or Nomic; or MFJ's model 1275.

The radio end of the interface plugs into the radio's microphone jack or, if the radio has one, the data jack. (In some radios, the receive audio must be obtained from the radio's speaker jack.)

The computer end of the interface will have 3 cables:

	The cable from the radio's audio output (RX) plugs into the computer sound card's Line In jack.
	The cable to the radio's audio input (TX) plugs into the computer sound card's Speaker jack.
	The cable to the radio's PTT (Push To Transmit) plugs into the computer's COM / serial port. (EchoLink triggers radio transmissions by putting voltage on a COM port pin, thereby activating the PTT circuit in the radio.)

Monitoring your station: If you run a radio-to-internet link station, you're obligated to monitor you radio's transmission. That can be a problem. If your only radio is doing the transmitting, then you can't hear what it's transmitting. You could of course use a second radio. For example, I use a hand held radio periodically to hear exactly what's being transmitted by the EchoLink base station (volume, audio quality, etc).

When I'm not using the HT, I do two things to help me detect transmission problems:

I listen to the internet stream on my computer speakers. In other words, I listen to what the radio should be transmitting. But listening to that can be a problem, too. Remember that the EchoLink audio is now going to the radio's TX audio pin, not to the computer speakers -- so I normally can't hear what the internet station is saying. My solution: I bought a line splitter ('Y' cable) at Radio Shack which lets me plug both my sound card interface and my computer speakers into the sound card's speaker port. (The 'Y' has a stereo input plug and two stereo output jacks.
I listen for problem reports from local users on the radio frequency: If there's a problem with my transmitted audio, other radio users usually say something. I'm fortunate that my radio's receive audio still goes to the radio's speakers even though I have a sound card interface attached. If your radio's speakers don't work when you have a sound card interface attached, try using the line splitter / 'Y' cable idea above. A splitter would let you send the radio's audio output to both the 'Line In' jack and an auxiliary speaker. (But you may need a different type of 'Y' cable -- a stereo input jack and an output jack and an output plug; or one with two output jacks plus a second cable with two plugs -- one plug going into the Y's jack and one plug going into the sound card.)

SysOp Settings

Here are some screen shots and comments describing how I've set up my link. They are not meant to tell you the "best" way to do it -- in fact, I'm still changing things as I learn more. But they may give you insights into settings for your link. I also encourage you to consult EchoLink's Help for each screen, since it will give much more thorough information about each switch setting.

1. To enter SysOp mode, use the EchoLink menu: Tools> Setup>My Station

į Click to see a larger image.

2. All the changes in this section are made from the EchoLink menu: Tools> SysOp Setup.

a. RX Control tab -these settings control how audio received from the radio will trigger internet transmissions.

I just left the defaults as is.

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b. TX Control tab - these settings specify how EchoLink will trigger a radio transmission.

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c. DTMF tab - specify DTMF codes that EchoLink will respond to if heard over the air.

You can either leave the default codes or pick your own. I found that any DTMF code with a 0 (zero) in was not heard well by EchoLink's DTMF decoder, so I changed all the codes -- and re-ordered them while I was at it. See my DTMF codes at About KC2RLM's EchoLink Station

d. Ident tab - settings determine what the EchoLink program announces on the air.

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e. Options tab - additional settings that determine what the EchoLink program puts on the air.

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f. Signals tab - further controls for "on air" announcements

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g. Web - option to allow remote control of the program over the internet.

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Using Web Remote Control - Enter the IP address of the EchoLink computer to be controlled in your browser's address window. When you connect, you will first get a screen asking you to enter the Username and Password (as specified above). If you do that successfully, you will receive the screen below with control options for:

	open and close the connection to the radio
	connect to and disconnect from stations
	transmit the station ID.

The http address in the sample screen to the left -- 127.0.0.1 -- is the universal address for "the computer I am sitting at". A remote control operator would need the actual IP address of your computer to access this screen over the internet.

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3. Now use the EchoLink menu Tools>Adjust Volume>Recording to get to the Recording volume settings window. This controls the source of transmitted audio. For SysOp mode, you want the radio (or Line In) to be the source.

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Select "Line In" (Radio RX audio) as the sound source, instead of "Mic Volume". The "Line In" volume slider can be adjusted up and down depending on the strength of the radio's RX audio. Use the audio meter at the bottom of the EchoLink screen to determine the best position for the slider. The meter should jump at least halfway on voice peaks, but should not go full-scale. If you see yellow in the bar to the right of the blue, the audio setting is too high. The red bar is the highest recorded level since the audio started.

I set the VOX threshold fairly low. If you set it too low, the radio may continue to key the internet stream forever. Too high and the internet stream will "stop-and-go" whenever someone pauses slightly, i.e. a carrier with silence. So I try to set it at that point between the audio level for no carrier and a carrier with silence.

4. Use the EchoLink menu Tools>Adjust Volume>Playback to get to the Playback audio settings window. This sets the volume of any audio to be transmitted by the radio, i.e. the internet audio feed and any program announcements. Use the "Wave" and "Volume Control" sliders in tandem. Again, use the audio meter (graphic above) to help you gauge the best volume level.

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