Hints and Tips in using the Tigertronics SignalinkUSB
External USB Sound Card and Interface
(FINE PRINT NOTE: This page will be a work in progress!)

Ain't it cute??

First, what is the Signalink USB?

The Signalink USB is in fact an external USB monophonic sound card and radio interface. It plugs into a USB2.0 port on a computer. It will not work properly on USB1.1 ports. It is powered from the 5 volt buss in the USB port. The unit offers front panel controls for TX and RX audio levels, as well as PTT un-key delay. There is a power switch and led, as well as a PTT led. It is an AFSK mode device. It will only do audio frequency shift keying, however will do EVERY mode that is AFSK. (See note 5 below for true CW operation.)

Going to the rear panel, there are the following jacks:

Speaker (SPKR) (1/8" jack) (input from radio speaker jack if RX audio not available in data jack)
Auxilary (AUX) (1/8" jack) (output to speaker when using Auxilary jack for RX audio)
Radio (RJ45 modular)
Monitor (MON)
(1/8" jack) (a set of headphones or computer speakers can be used to monitor TX audio)
USB (USB "B" connector)

Inside the unit, you will find a good amount of surface mount components, some two pin jumpers, and a jumper block that uses wires to set the unit up for a particular radio. When you purchase a Signalink USB, it comes with instructions, a USB cable, a hex key wrench, wire jumpers, an 1/8" mono to mono cable, and a radio cable is included (your choice).

The instruction manual details how to set up the computer for use with the unit, as well as how to set up the unit, thus I will not cover all of that here, but will give a few important pointers:

1) The Signalink USB will probably have to be plugged into a USB 2.0 port to work properly.
2) When you follow page 3 in the Signalink USB manual, "Sound Card Selection", once you have selected what you need, restart the computer. Also, each time you have configured a specific software for the Signailnk USB (MixW, MMTTY, etc), close the software and restart the computer. This lets the computer write your settings to the registry.

Now for "hints and tips".

1) For some radios, such as some Yaesu FT-450's, the TX audio may be so loud that the front panel TX control on the Signalink USB will not control it properly. It is suggested in this case to remove the "MIC" jumper inside the Signalink USB and replace it with a 100K 1/4 watt resistor (brown, black, yellow). If you multiple radios that require the same type cable, and the other rigs won't work with the resistor, my suggestion is to add the resistor to the cable and leave the wire jumper in the Signalink USB. I suppose one could leave the resistor in the Signalink USB, and add a shorting switch to the rear panel of the unit (but DON'T do it until the warranty is out!). I run the FT-450 and a FT-8800 and both work fine with the resistor. I will be trying it with an Icom IC706MKIIG in the future, and will post info on that set up later. Also, if you plan to "Y" connect the Signalink USB with a TNC to the same jack on the radio, you might want to replace the PTT jumper with a small signal diode, such as a 1N914. The band would go towards the radio.

2) You will find with some modes, such as CW and EasyPAL digital SSTV the Signalink USB will drop the PTT before completing transmission. Simply crank up the DLY knob to correct this. For my unit, I run the control at 2:00.

3) You may also find with some modes, you may need different computer audio settings. Simply pull up the Windows Volume Control for the USB Audio CODEC and adjust them. I have found with EasyPAL that the WAV slider needs to be a little higher. I also recommend running a little widget called QuickMix that will memorize your volume settings in Windows for recall later.

4) Do you want to be able to do true CW with your SignalinkUSB? Take a look at this page on the Tigertronics web site and click on the "1. How do I operate "direct keyed" CW with the SignaLink?". One thing that is not mentioned in the FAQ is that is you plan to receive using the SignalinkUSB, you also need to connect the RX audio to the unit.

5) You will need to do a calibration routine for software setup. Most of the latest software for digital has some way to do this procedure.

Need to be able to swtch between radios and not switch cables? Try a RJ45 A/B switch! You can find these for $20-$25 on eBay, and Buxcomm also carries them. I am currently working on a design which will allow me to switch between two rigs, the Signalink USB, and a TNC. See the diagram below:

To setup the Signalink USB and a TNC to the same radio port without a switch (such as for WL2K RMS operation), try this hookup:

If you are serious about Sound Card Digital, buy a Signalink USB!
See http://www.tigertronics.com for more info!