Home   Fox Delta  Projects School Projects Buy PCBs Buy Kits Contact   
 Introduction to Sound Card Interface & Radio Modems:


For many radio amateurs, talking & chit-chatting on-the-air is of no interest. They rather like to "Silently" work on their bench with hobby projects & communicate with fellow amateur by way of a PC and a modem connected to wireless set.

There are lots of ideas & radio modems available to fill this requirements. I have gone thru this 15 years back when I first bought a Kentronics all mode TNC and later a 1200baud VHF TNC. 

Here I have presented two such "Modems" which are not really modems but give us the same results at a fraction of cost.

The first is called "Hamcom" a PC software (DOS) written by  . It has a very simple interface to PC com port containing a ua741 and few components. Most work of a "TNC" is done by the software.

You get a simple, economical & fast way to start digital communication on amateur bands with this kit & a free software. With Hamcom you can receive & transmit RTTY & CW.

Similarly, PC's soundcard is nothing more than a modem itself. Using soundcard capabilities for Digital Communication has attracted many hams to use a simple interface to isolate PC & Radio to achieve clean signals & reject noise and spurious frequencies.

Sound card Interface detailed below does this and more. SC2 designed recently, includes COR isolation making it a simple EchoLink interface too.

 Sound Card Interface for Amateur Radio Stations:
SC1: Simple Sound Card Interface

SC1 provides isolation between PC & Radio by way of using Transformers for MIC & RX audio and an opto coupler for PTT line. D9F connects to your PC for PTT control.

SC2: Sound Card & Echo Link Interface

SC2: Sound Card Interface with Echolink interface


Advance Sound Card Interface now supports Echolink and VOX

TinyEcho Interface

Although named related to "EchoLink", This is nothiong but a sound card interface with added isolation for COR. Uses quality Bourns SMT Transformers and has RJ45 socket for Transceiver connection.

 Project Categories: