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[W6NZX]

I know I can split the audio out to my 2nd machine to watch the wave form, but is there anyway other then that to monitor what your sig LOOK like.

This is for PSK BTW.


-Rob

[KF6IIU]

Just ask the ham on the other end for a report! Works great for me.

[W6BP]

If you're looking at the audio as it leaves the computer, you're not looking at the audio as transmitted, so you may be overlooking problems.  For example, if you're getting distortion from overdriving the transmitter, you'll never know.

There are a few options:

1) You can buy an IMD meter to monitor your transmitted PSK signal:

http://www.eham.net/reviews/detail/4210

2) You could use a monitor receiver.

3) You could ask another ham to monitor your signal; some PSK software will report the IMD when you transmit idles, i.e., no text.  There are a few pitfalls to this.  If you contact someone very close to you, overloading their receiver could introduce distortion that your signal doesn't actually have.  And if your signal is too weak at the receiving end, the other guy may see an IMD number that's too high, because the sidebands are below the noise.

[G0GQK]

Just make certain there is no ALC showing on your tranceiver, don't use more than 30 watts output, and see that the processor is switched off. Do that and your transmission will be as clean as a whistle. You can ask people for IMD reports but my experience is that they vary quite considerably. In one afternoon I've had from -17 to -28 and nothing was altered to give such varying reports.

G0GQK

[KI6LO]

If you seriously wanting to monitor the quality of your signal of PSK31, asking someone on the other end of the QSO is a really poor way of doing it. The ability of the receiving person to analyze the signal and give you proper feedback varies greatly from person to person. Many hams believe that if they can copy you, then all is well. Not necessarily so.

You should be monitoring it at the source to ensure it is within limits. To this end, I would recommend you investigate the PSK Meter. I have no interest in the success of this product, but find that it works really well for what it is designed to do.

Check it out at http://www.ssiserver.com/info/pskmeter/

Gene KI6LO

[AA4PB]

Very true. IMD can be created ANYWHERE in the signal chain including the other guy's receiver, interface, or sound card. I no longer get all upset if I get one bad report (been down that road). Its much better to have an IMD meter to check it out for yourself.

I've done some "in house" testing and find that with an S-9 or better received signal the received IMD reading can degrade by about 10dB just by changing the AGC speed setting. The AGC in the receiver can have the same effect (adding distortion) on a signal as the ALC does in the transmitter.