K3PP

The GYT Special


Sometimes, the best ideas are the simplest.  One of these is the GYT Special, a cheap and simple alternative to the costly commercial computer interface for Icom's radios.  Bob Schreibmaier, WA3GYT (now K3PH) designed this clever device using two standard diodes, one Zener diode, and two inverters.  The total investment, if you had to actually buy everything, is about US$5.00.  Compare that to Icom's CT-17 commercial interface that costs well over US$100.00 and requires a separate 12v power source.  

Click on the following images for more detail:

This image shows Icom's CT-17 in the center of the picture.  Wrapped around the CT-17 is a length of RG-58 coax  with a modified GYT Special I built using a 4001 quad NOR gate (I had no inverters handy, but I did have a 4001!).  The entire circuit easily fits inside a DB-25 connector for the computer's serial port.  The circuit needs no separate power supply because it draws power from the computer!  Virtually any coax would suffice for the interface.  I just seem to have miles of RG-58 lying around! The connector on the other end plugs into the Remote jack on any Icom radio.


This is a close-up of the circuit inside the DB-25 connector shell.
Last Updated on 07 September 2001
By Glenn O'Donnell, K3PP
Email: [email protected]