Getting your first HF rig and have no idea what most of the buttons are for? I had a hard time figuring that out at first too, the manual seemed to assume I would know and the descriptions I found online were too cryptic to decipher.

Since this blog does very well in search engines I guess it may help a few folks out like some of my other articles, and I may keep adding to it as I discover new things.

So here are a few controls I figured out on my IC-735 that have made me able to really pick up those weak signals from overseas, your rig probably has the same type of controls since this is a fairly simple rig.

PBT knob: This extremely useful thing acts like a sort of audio window shade. If you turn it to the right (or left on LSB ) it will cut out all the high frequencies coming through, narrowing down the frequency range you receive. This is VERY useful on digital modes as you can completely block off one side of the waterfall and reject strong incoming signals leaving your receiver still sensitive enough to pick up the weakest signals. Turning your PBT knob the other way will of course cut out the lower frequencies. Very nice for quieting adjacent signals that are interfering with you.

This feature is not found on some other radios but instead they will have other filters (such as a DSP) that let you “squeeze” the signal reception window into a very narrow passband in a similar way.

Notch Filter This is a bit easier to understand. Combined with the PBT and RIT controls you can really narrow down your receiving frequency range and reject nearly everything outside of a 100hz window. What this means is more sensitivity and a lot less interference. The notch filter is the opposite of a bandpass filter, it only blocks about a 500hz wide section of frequency. The control will decide where in the receiving window you are blocking. I tune the notch filter by ear to block anyone transmitting with excessive power (and desensitizing the receiver) and I also use it to cover the other side of the signal from the PBT. This has a little more reach than the PBT on my rig.

RIT knob This knob is sort of a tuner within a tuner. It shifts the frequency in smaller amounts than the main tuning knob and does so without changing the receiving frequency. It appears that it just changes the audio pitch which may be useful for a number of things, but probably most often used to tune down a CW signal to a pitch that is more comfortable. I haven’t used this that much, so maybe some others can comment on how they use it.

Finally if you’re just getting started with PSK or similar you absolutely must watch the following video by K7AGE. He tells you step by step how to tune up correctly for these narrow bandwidth modes. Failing to do this the right way will get you scolded, trust me