PSK31 Transmitter Level Adjustment

Two points, but first of all, great video. TKS!

First, the reason ALC is kicking in before "full power" is indicated is because of the difference between Peak and Average power. You are putting out full power just before ALC kicks in, even tho you don't see it on the meter. Second, I use an audio pad between the computer and the rig which allows me to operate audio more toward the linear region of the sound card (and it gives me a wider range to fine tune the audio level). 73!

Something that should be said. For psk, the "carriers" (the tone with no data transmit) is 80% duty cycle. So to stick with the ft817 here, 4watts is about what you would want to see with no data send. It will have its peaks at 5 watts. If you notice, if you note, at that point, his alc was still at one bar. Idealy, your digital station should never light the alc up ever! The difference here is that the alc is an peak meter, the watt meter is an averaging meter.

Thanks, the various different meters does confuse people, plus radios also react differently. I hope that most that view are able to get the audio set low enough so not to be wide across the band! Randy

Well, it will never fully go away. I mean, you had people doing this with rtty years ago, as well as sstv, although when you overdrove those modes, you knew it right away, especially sstv. Bob, all i got was static!

What really causes this is people trying to get the last watt from their radio. Its digital folks, that last 10% isn't going to matter.

Most software, the tune tone should be used to tune, and nothing else, as the modes are programed in such a way to match that tune tone.

Nice demo; It was a great idea using a second radio set to receive the transmitted signal to show how IMD (Inter-Modulation Distortion) W-I-D-E-N-S the transmitted spectrum thereby clobbering the adjacent signals!

Dear Randy,
Thank you for excellent video's. All of them are very useful. After 30 years of cw operation I decide to buy MK2:-) With your help just in few day's I did more than 50 qso's with 30 watt's on 7mhz, :-) wow! No TVI, no angry faced neighbors!
Nice fun with out QRO.

YU7BH

have fun!

that way it would be hard to mess up the audio settings in the mixer program just keep it full blast all the time. I also recommend getting a 2nd pci sound card so windows and webpages sounds don't get transmitted out. That way you can jam to music while in QSO with your friend on psk .. Hope that helps as well , tnx for the vid 73 to all

I usually set mine up by the forward output and make that needle bounce as much as possible it will hit 100watts sometimes but, not all the time! when no text is going thru it should be at least 25% weaker than pep. bpsk31 is not 100% duty but, pretty close. in mixw there is a neat feature for audio levels called Amplitude level for this mode. set to 1.000, 1.000 is full output audio set to around maybe .3 to start and see if you can hit 100 watts. continued

yea that is one of the big myths out there about strong bpsk signals. no matter what power setting you are at you can have a dirty signal. Some things I seen out there that can cause some problems is ground loops, a sound card with high THD% , EMI from other equipment or AC lines, RFI from the actual transmitter getting into the audio lines or chassis. one thing I found on some rigs out there is that the ALC meter will read wrong somtimes.continued