Operating digital is something that most of us seem to learn more or less on our own, with the (huge) help of the internet, with all of its resources. One of the things that frequently surprises me are some of the myths and misconceptions that are common among digital ops. Here are a few.
1. Power does not matter for digital modes. I have run into numerous ops who believe that since modes such as PSK are "digital," the power level that they run does not matter. They doggedly will stick to 10-20 watts even when characters are dropping out and readability is 'way under 100%. While it is true that these modes often do very well at low power levels (20-40 watts is common) it is also true that in today's often poor band conditions, more power will sometimes, even often, yield much better communications with fewer characters missed. If you are in a QSO and copy is rough, it is OK to raise power if you can! Going from 20 to 70 watts often will make a tremendous difference on all of the digital modes. Yes, even Olivia. Naturally, one must keep an eye on the rig's duty cycle, as most digital modes are high duty duty cycle. Some of this QRP habit derived from the fact that PSK emerged at a time when the sunspot cycle was at its peak. Under such conditions, low power produced much more consistent and reliable contacts. Under today's conditions more power is often justified. CW is a digital mode--the first. While some CW ops run QRP (nothing against QRP!) plenty more run the legal maximum, and most run power at their rig's usually 100 watt limit. PSK and other modes benefit from a bit of power very bit as much as does the "first" digital mode. 2. Filtering is unnecessary for digital modes. Just plunk your rig in the middle of the PSK (or other mode) band and change frequency with the soundcard ("moving the flag.") Narrow filters are a Godsend with most of the digital modes. The digital portions of the band are not large, and are full of signals. You want to have the station you are receiving at the center of your rig's audio passband (typically either 1000hz or 1500hz). This means that you tune with your radio, not the soundcard. This way, most rigs will enable you to use the radio's narrow filters such that placing the received signal in the center of the rig's passband creates a "wall" that protects the signal from all but the closest adjacent interference. Good digital programs like MixW and PSKDeluxe have functions for centering a signal in the rig's passband--MixW's "ALIGN" command, and the "Center" function in PSKDeluxe. This is why IF filtering is so important--it prevents strong adjacent signals from desensitizing your radio by pumping the AGC. When picking a rig for digital operations, in my opinion the single most important factor is what kind of narrow filtering the rig provides for digital mode operations. Good filtering during a QSO will often make the difference between solid copy and no copy. Often, when someone calls me, I can barely copy them until I kick in the narrow filters. Then, because nearby interference is no longer desensitizing my radio, the caller is Q5 copy. Just some random thoughts. Hope this post is not too long or too boring, grin. de Roger W6VZV