Getting Started on RTTY - Page 9
Commercial Sound Card Interfaces
If you choose not to build your own audio interface cables or FSK/PTT interfaces, you can buy a commercially built sound card interface.
There are several commercial sound card interfaces available. All of them should work with MMTTY and nearly all of them come with cables to interface to your transceiver (you must specify which cable you need). However, not all of them are capable of keying FSK. If you are using AFSK, they all should work. Four manufacturers and their products are included on this page. They are the RIGblaster models by West Mountain Radio, MFJ Sound Card interfaces, the RASCAL GLX interface by Bux Comm and the SignaLink Model SL-1+ by Tigertronics. Only basic information on each model will be included here. For more specific information, refer to each manufacturer's website.
The RIGblaster
The RIGblaster may be the most popular brand of sound card interface. There are four models to choose from - Nomic, M8, Plus and Pro. All work with MMTTY.
The most basic unit is the Nomic. The next model in line is the M8. Both the Nomic and M8 do not support FSK keying or a separate stand-alone PTT output. These units are for AFSK operation only by offering an audio interface between the sound card and transceiver for both transmit and receive. PTT is connected to the radio's mic input. Gert, K5WW, did build an FSK keying circuit inside his Nomic. See http://www.qsl.net/k5ww/HTML/FSK.htm.
The Plus and Pro models fully support FSK (and CW) operation and have a separate output for PTT in addition to PTT on the MIC connection. The Plus model outputs CW and FSK on the same jack though. In order to change from CW to FSK, jumpers are changed inside in the unit. The Pro model has separate FSK and CW outputs as well as a full compliment of connections for two radios.
MFJ Sound Card Interfaces
MFJ offers two interfaces - the MFJ-1275 and MFJ-1279. Both work with MMTTY. The MFJ-1275 does not support FSK, but the MFJ-1279 does. However, like the RIGblaster Plus, FSK and CW share the same output on the MFJ-1279.
RASCAL GLX by Bux Comm
Bux Comm offers one basic unit. It comes in three flavors - Black, Beige and kit form. All three are the same interface and will work with MMTTY. The GLX supports FSK keying. Bux Comm offers a very large assortment of cables to interface to just about any transceiver made.
SignaLink SL-1+ by Tigertronics
The SignaLink SL-1+ offers a unique circuit that senses audio from the sound card to activate PTT. Therefore no connection to a serial port is required. This is great for use with newer laptop computers that do not have serial ports. However, it does not run FSK and must be used for AFSK operation only.
