You could use an external device as others have suggested. I don't generally recommend the SignaLink USB due to the low frequency noise problem, however many hams either ignore it or are not aware of it. Further, after some considerable denial on the part of Tigertronics, they may have corrected this in later versions, but I can not yet confirm that.
On the other hand, I do recommend the SignaLink USB for the simplest possible portable unit such as might be used for public service/emergency communications and you don't want to be concerned about COM ports or USB to COM adapters. Just plug in the USB to the computer and plug in a rig specific cable and you can operate. My personal lowest cost solution is to use an add on 24 bit sound card that connects to a hard keying PTT optoisolator interface. If you are handy at simple kit building, I can heartily recommend the Unified Microsystems SCI-6 Interface at only $25 plus about $5.50 US S&H. I have almost all ICOM equipment, so I also use the West Mountain RigTalk USB to CI-V interface for an elegant way to provide the rig control interface connection. In order to do this you will need two COM ports or two USB to COM adapters, but it gives you the flexibility of being able to key the rig even from software that does not provide rig PTT keying via rig control. As mentioned elsewhere, the ARRL had tested several sound cards, however as I recall they found that for digital modes, of the ones they tested, all worked equally well. (They did not test the SignaLink USB, however). They did find that a very high quality card is needed if you are using it for interfacing with DSP systems such as Flex Radio. 73, Rick, KV9U lsumners wrote: > I am looking at upgrading my Dell on board sound card. Any suggestions for > digital radio? > > > > ------------------------------------ > > Announce your digital presence via our Interactive Sked Pages at > http://www.obriensweb.com/sked > > Recommended digital mode software: Winwarbler, FLDIGI, DM780, or Multipsk > Logging Software: DXKeeper or Ham Radio Deluxe. > > > > Yahoo! Groups Links > > > > ------------------------------------------------------------------------ > > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 8.5.339 / Virus Database: 270.12.76/2183 - Release Date: 06/17/09 > 05:53:00 > >
