SignaLink SL-1 & SL-1+ Troubleshooting FAQ

This FAQ contains test procedures, troubleshooting tips and common problems for the SignaLink™ SL-1 and SL-1+ Sound Card - Radio Interface.  For non-technical questions, please see our SignaLink™ SL-1 & SL-1+ FAQ.

Troubleshooting Procedures

  1. Common Problems - Virtually ALL problems experienced with the SignaLink are addressed in this section.  Please read thoroughly before calling for assistance. 

  2. Setting Audio Levels - You MUST set your sound card audio levels or the SignaLink may not work properly.  Please follow this detailed procedure if you have not already done so!

  3. Sound Card Test - If you've gone through our troubleshooting tips and level setting procedure but are still having trouble, then follow this procedure to verify that your sound card is actually working. 


Common Problems

These are the most common problems reported to our Technical Support Staff.  If you cannot resolve your problem, or if you do not find your problem listed here, then please contact our Technical Support Staff for assistance.

  1. Radio won't transmit (SignaLink's PTT indicator is OFF).

  2. Radio won't transmit (SignaLink's PTT indicator is ON).

  3. Radio transmits, but power output is too low.

  4. Radio "flutters" between transmit and receive.

  5. My transmit signal is wide and distorted.

  6. I can't seem to receive.

  7. Why can't I receive some stations.

  8. Windows System Sounds cause my SignaLink to transmit.


Radio won't transmit (SignaLink's PTT indicator is OFF) -  It is important to remember that the SignaLink keys the radio automatically when it detects transmit audio from the sound card's Speaker/Line output jack.  If the PTT light on the SignaLink is OFF, then it is most likely because the sound card PLAYBACK volume controls are set too low, or the cabling between the SignaLink and the sound card is incorrect.  Verify/check the following:


Radio won't transmit (SignaLink's PTT indicator is ON) - If the SignaLink's PTT light comes on but the radio doesn't transmit, then you have jumpered the PTT and/or Ground pin incorrectly on JP-1.  This should not be an issue if you tested the PTT line as outlined in the jumper section.  If you find ANY jumper connected wrong then we recommend that you go through the entire jumper installation procedure again.


Radio Transmits But Power Output Is Too Low – The RF power output of your radio is determined primarily by the amount of sound card speaker audio that reaches the radio.  If your radio isn't putting out enough power, then more than likely, you just need to raise the sound card's PLAYBACK "Master" and/or "Wave" volume controls, and/or the SignaLink's  internal "TX Level" control (SL-1+ only).  However, there are other controls that also effect the power output, so we strongly suggest that you follow our Audio Level Setting Procedure if you haven't already done so.  If you have already been through this procedure, then we suggest that you repeat it, paying careful attention to the final step involving setting the transmit power level.  If you are still unable to reach the desired power level, then please contact our Technical Support Staff for assistance.


Radio "flutters" between transmit and receive - This is caused by an incorrect software volume control setting on your computer.  It happens when Receive Audio from the radio enters the sound card's mic or line input and is fed back out the sound card's speaker output.  To fix this problem, you need to open the PLAYBACK volume control panel and MUTE the "Microphone" and "Line In" volume control.  Be sure to disable the Mic/Line In control under PLAYBACK only (NOT Recording!) or you will not be able to receive!  


My transmit signal is wide or distorted - This is generally the result of over-driving your radio, but there are other causes.  Your radio's speech processor/compressor should be OFF.  Your sound card's “Bass Boost” or “Audio Expander” features should also be OFF.  Verify that your radio's "RF Power" or "Forward Power" control knob (or menu item) is set to provide maximum RF power, and then try adjusting your audio levels again using our Audio Level Setting Procedure.  If you are unable to correct the problem, then please contact our Technical Support Staff for assistance.


I can't seem to receive - There are several possible causes for this problem:


Why Can't I Receive Some Stations - No matter how good your antenna and radio are, there will always be some stations that you cannot copy (even with strong signals!). While the reason for this may be because of operator error (wrong mode or baud rate, off frequency, etc.), radio wave propagation problems can often prevent you from receiving.  Some modes are more susceptible to this than others.  For example, even though PSK31 usually works very well with weak signals, sometimes even strong PSK31 signals cannot be copied at all because of multipath and Doppler Shift propagation problems.  Other modes like HF Packet and RTTY do not work well with weak signals and are susceptible to multipath and Doppler Shift.


Windows "System Sounds" Cause The SignaLink To Transmit – Since the SignaLink is activated by sound card output, it is important that it is turned OFF when not in use.  The sounds that are generated by Windows during different system events (Startup, Shutdown, File Close, etc.) can be transmitted if they are inadvertently sent to the SignaLink.


Sound Card Test Procedure

If you are having unexplainable problems or are simply not sure if your sound card is working at all, you can use the following test procedure to verify sound card operation.  This test uses the Sound Recorder program that comes with Windows to test your sound card’s record and playback functions.  Before you begin the test, you need to verify that your computer speakers are plugged into the sound card and that all programs that use the sound card are closed.

To test the record function of the sound card, we need to have an audio source connected to the sound card's Microphone input.  We will use your radios external speaker output for this purpose.  Disconnect ALL CABLES from the SignaLink before you start this test.

Before we can record a signal, we need to adjust the radio and computer volume controls.  Please note that the volume settings used here are for test purposes only.  The controls will need to be re-adjusted later using the “Detailed Procedure To Set Audio Levels”.  For now, adjust the audio level controls as follows:

Figure 1 – Volume Control Panel

Figure 2 – Sample Properties Page

Figure 3 – Record Properties

The Volume Control panel should now show only the Recording controls.  It should look similar to the picture shown below.

Figure 4 - Record Level Controls

Now that the recording and playback controls are set to a usable level, we are ready to record and playback a test sound. 

Figure 5 – Sound Recorder Screen Shot


Sound Card Problems

While Tigertronics does NOT provide support for sound card problems, we have listed a few troubleshooting tips here to help you with some of the most common problems.  If you are unable to resolve a problem with your sound card, then you will need to contact your computer’s manufacturer or a computer repair shop for help.


Detailed Procedure To Set Audio Levels

This is a “Step-By-Step” procedure to assist those who are not already familiar with setting sound card levels using the Windows Volume Control Panel.  Before you operate your SignaLink on the air, you will need to adjust the Receive and Transmit Audio levels.  Incorrect adjustment of these levels can cause poor reception, over-modulation, or improper operation.  This procedure will show you how to adjust your sound card and radio audio levels for optimum performance.

Before you can adjust the audio levels, the SignaLink must be connected to the sound card and radio.  Both the SignaLink and the radio should be powered ON and a communications program that you have selected should already be installed on your computer.  Note that we will be using the communications program to generate the audio tones that are used to adjust the level controls, so CW programs should NOT be used unless they have a continuous "Tune" mode.  A program like DigiPan is ideal.

NOTE:  Be sure that your radio is connected to an antenna or dummy load before proceeding!  Once you have properly adjusted all controls, your transmit power level should be NO HIGHER than that recommended by the radio manufacturer for continuous duty cycle transmissions (check your radio manual!).  Do NOT transmit at a level higher than that recommended by your radio manufacturer, or you might PERMANENTLY DAMAGE YOUR RADIO! 


Follow the steps below to set your transmit audio level.

Figure 6 – Volume Control Panel

Figure 7 – Playback Properties


Follow the steps below to set your receive audio level.

In the “Show the following volume controls” window, verify that the Microphone box is checked.  When you are done, the Properties window should look similar to the one shown in Figure-8.

Figure 8 – Recording Properties

Figure 9 – Record Level Controls

The sound card's volume levels are now properly set. Any further adjustments should be made using the radio's Volume control. Click the "X" in the upper right hand corner of the Volume Control window to close it and save your settings.


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