When I attempted to answer someone’s PSK31 CQ I noticed my RF power was averaging about 30 watts, but peaking at 70 or so.

I doubled checked various knobs on the US Interface Navigator, software, etc. Everything looked fine.

I transmitted again. The peak power was still there.

I knew this was not right and I was frustrated. I then recalled the power meter correlated very well with the sharp clicks coming from my kid’s air hockey table in the next room, but how could that noise be getting in and if it was, why was it having any affect from so far away.

Aha… the “MIC GAIN” on my Icom 746 was still up meaning the microphone on my Hail headset was still live and mixing with the audio from the Navigator.

Plus, the staccato noise from an air hockey puck smacking against the handle is a lot louder than it might seem because it is so short.

I turned the mic gain down and all is well.

I have not found an automatic way of muting the microphone input during sound card transmit with my IC-746. Have any of you found a way to do this?

73
kx4o

You have gone the next step and know you need to, somehow, connect your computer soundcard with your radio’s speaker and microphone.

Many devices exist to help you do just that including US Interface, BuxComm, SignaLink, etc. I have my eyes set on the US Interface Navigator product to be my sound interface plus mop up a WinKey CW Keyer and rig control (CAT) in one box entirely powered by the USB port. Nice.

However, I am enjoying the digital modes today with absolutely no interface. How?

Simple.

I was given a small computer microphone. This one is the type that is meant to sit on the table and pick up conversations nearby. I have it sitting directly over the speaker hole of my Icom 746. I fire up my MixW and easily decode the PSK31 signals in the waterfall.

What about transmitting?

That’s a little less polished, but functional. All I did was take the voice microphone off its stand and lay it next to my laptop. The computer’s internal speakers provide more than enough sound to send a PSK31 signal literally over the air in the shack to the microphone and out the radio. In fact, I had to turn the audio gain of the transceiver down a bit to make sure I was not over-driving the modulation.

I use my foot-switch to put the rig into transmit and then tell the software to begin sending PSK31.

From Virginia I have made easy contacts with Mexico, Kansas and Indiana using PSK31 in just two nights.

So if you are saving your money for a built interface or collecting ideas for a home-brew approach, GREAT, but go ahead and get on the air now using your rig’s microphone (TX) and a cheap computer microphone (RX). Remember to keep the transmitted audio levels lower than you think are needed. If you don’t you will splatter your signal all over the PSK range.

I am quite surprised how sturdy PSK31 is to make a trip in the air of my shack, but it works remarkably well.

Coordinating the foot-switch with the computer program transmission is getting old quick, but for the low price it buys you time and gets you into digital modes today.