Receiving two separate signals on the same band
|Click on each image to enlarge|
I wanted to try some simple stuff with the new sub-receiver at first as I had not yet dove into the manual to learn the details of the KRX3. With the two receivers on the same filter (Dual pass band) on the main receiver I found one CW signal in a QSO with another station at 7.013 (in my left ear). Then with sub-receiver I found another station at 7.034 in a QSO (in my right ear). It worked and sounded great I was even able to use different filters and depending on noise conditions at either end of 40 meters use separate NB, NR, ATT, or other filter settings. I recorded an audio sample this is from my 20 meter dipole in the attic. At first you will hear both signals then just the sub receiver (7.034) then both and the the main receiver (7.013). Both of these signals I used the dual bandpass filter.
The audio clips are best if listened to with stereo headphones.
Same band separate QSO's audio sample
This feature is useful in contests when a station I want to work (a multiplier) is involved in a pileup. I can keep them on the sub receiver and work other stations with the main receiver. The sub and main have independent volume controls. The sub-receiver can be lowered and checked in on now and then to see how the pileup is going. When the pile up thins down I am able to hear it and then take the opportunity to work the multiplier.
Working a DX-pedition
DX-pedition audio sample.
Receiving two signals on separate bands
Now because the KRX3 is a totally independent receiver you are able to listen to two separate bands at the same time. The main receiver was on 20 meters and the sub was on 40 meters. (using the same antenna) Again in contesting this can allow me to check another band to see if it is open or closed for action. You also could set the sub for your weekly 80 meter skid. While waiting for it to start make some contacts on 40 with the main receiver. In the audio example you will hear 20 meters on the main VFO then the sub were a station is calling CQ on 40 meters. The audio goes back and forth as well as both bands at the same time.
Two separate band audio sample
I consider having two independent receivers to be a great asset, but then there is the ability to listen on one antenna and transmit on another this is called diversity receiving. In my case I have a 20 meter attic dipole and a High Sierra Sidekick outside at the side of my deck. Not a super station but along side the Elecraft K3 it's getting my signal out there. I use the dipole as my receiving antenna as it is horizontal and quiet, the Sidekick is the transmitting antenna. If I was just using the vertical I found I missed out on signals that were close to the noise floor. The dipole was able to pick these up and I was therefore able to work more stations. On Thanksgiving Monday I was giving the diversity mode a workout, at this point I don't understand it well enough to go into any detail. I will dedicate more time to this mode next weekend. I will blog on the diversity mode then I just want to make sure I understand it fully so I can give this mode it's due credit.