VARIOUS CIRCUITS

 

 

 

PTT circuit from your pc - stops rf getting back into the pc

PTT circuit from your pc - stops rf getting back into the pc

You could use this cct with a usb to serial port convertor - you will need some kind of interface if you are going to use one of the rtty / uiss programs.  If your computer has still got a serial port then you won't need the usb convertor.

 

 

 

 

 

 

more simple ptt circuit

A circuit to improve the reception of navtex when the receiver

being used is not so good at 518khz

PTT circuit - you might still get some r.f feedback with this cct

 

 

You will need these two items if you opt to build the above interface for usb, or just the db9 if your computer still has a seriel socket

 

to prevent your tcvr being over driven use the top simple attenuator cct

use it with  the simple 4n25 ptt circuit

for audio from the tcvr into the pc souncard via its mic socket use a strait forward patch cable