Currently on HF i use a ICOM 706MKIIg which seems to perform very well for an all band radio and much is much better than the Kenwood TS-680S i used to have, covered from below 100KHz right up to 60MHZ and thois is very useful for listening for 6m openings. The first HF tranceiver that a got was another Kenwood but then called Trio TS-430S which eas a great little radio and included all of the extra filters for good measure!
For use when i had my Foundation licence i found it very easy to modify for QRP power by applying a negative bias voltage to the alc input (using a 9v PP3 battery) that is easily accessable on the rear AUX connector.
I think the 680S was better than the 430s and seeed to be a little better when the band is crowded but the controls on the right side of the radio are sliders and not rotary controls, these can be very tricky to get in the right position!
Recently (2006) i have also been working on a home brew HF tranceiver based around the Cumbria Designs IF System. I have currently go the IF, DDS VFO and BPF stages completed. The cumbria designs IF kit is an excellent starting point for any tranceiver, you should give it a go!
This is how my radio looks so far se to 20m band.
FILTER/AGC/CW+SSB/LSB+USB/MOX buttone across the top, AF gain, IF gain and Band switches to the right and main tuning dial in the middle right using a PC Mouse opto coupler, Hitachi LCD for frequency display (I need to learn to program PIC's before i add more to this!)
Project pretty much abandoned unfortunately, more intersting things to do on microwave bands...hi
I have not really used many antenna's on the HF bands but here is what i have tried until now. Firstly when i just had a HF only receiver (one of those Realistic DX-394's) al i had up antenna wise was a long wire strung out from the corner of the house and across the yard to the windmill whcih was not too bad at about 20ft high. It ws ok for listening but when i got my foundation licence and started to transmit it was causing allsorts of problems..not surprising! The next antenna i used was a homebrew full size G5RV antenna in the same place as the long wire was and the feeder was horizontal across to a pole on another shed. This worked extremely well on 40 and 80m and not too bad on 20m but was pretty useless above there.
Now i have a 20m/80m trapped dipole with home brew coax traps, I just use this for digital modes on 20M now, i dont make many SSB contacts on HF really, my main interest is on teh higher bands!i think i have worked more on 11m than i ever will do on the amateur bands, the interest has gone on HF for me mostly.. VHF and above is a lot more interesting.
Still to come... and it will eventually....... Sample DRM audio file from RTL on 6MHz (4.5MB) RTL Stereo sample
Updated 20th Feb 2008