Hi and welcome to my downloads page of circuits
Very simple audio attenuation for soundcard / txcvr use etc.
AF DERIVED PTT circuit from sound output from soundcard for PSK etc.
AF COMPRESSOR based upon the SSM2165 ic. PDF data sheet listed below this item.
AF AGC based on the TLO81 op amp
AMD Data sheet for the above SSM2165 in PDF format.
A non ground isolated method of using the 3.5mm audio jack on the FT847 for PSK etc.
High Pass Filter for use where intermod is a problem when using 144 or 432 MHZ.
IC706 Auto Tune circuit by G4FZN
Icom CI-V interface circuit with ptt, and cw key option
Icom CI-V interface circuit with ptt. Using MAX232 IC.
Mic Pre-Amp with tone controls. Excellent for electret inserts. Based upon ARRL circuit
Pulsed Tone Tune Up. Used to be called the woodpecker, it can be used to tune auto atu's etc
Pseudo Stereo CW....A project which gives a "Spatial" effect when copying CW
Simple Speaker Muting Circuit For Use With Soundcard Software's Like MMSSTV Etc
T Notch Audio Filter.....Try it out in series with your rx audio line to soundcard. Bust QRM
Simple circuits for switching a linear etc.
Simple variable voltage dc power supply 1.2 to 24V at 1.5A
Using DTR to switch on a radio cooling fan with EchoTime software
Yaesu interface circuit with ptt. Using MAX232 IC.
Very simple audio attenuation for soundcard / txcvr use etc.
"Arguing with an engineer is like
mud wrestling with a pig; After a while you realise you are getting muddy, and
the pig is enjoying it"
