I was pleasantly surprised by the Flex 6500 contesting suitability and very impressed with the level of engineering behind this radio. The receiver really stood out with a low level of "hash" and absolutely superb rx audio. The DAX digital audio virtual soundcard connection worked flawlessly with N1MM Logger+ and made ssb voice-keying a snap. Although the monitor audio is admittedly taken off before processing, I’ve never heard such pristine playback of my voice in my headphones before.
The SmartSDR waterfall trace is hands-down the best looking color waterfall I've seen and never needs to be tweaked (yay!!!). During some stretches of the contest, I used two “slices” to implement SO2V, routed slice audio to L and R channels, and rapidly pulled bandmap spots into each slice/vfo, working them in rapid succession (see http://n1eu.com/n1mm/cwso2v.htm for more info on this technique) and the 6500 performed flawlessly.
I view my 6500 ownership now as a test/audition for a decision to go “all in” with a 6700, since I’ve been using stereo diversity operating almost exclusively for the past ten years (dual rx Orion/RX366, K3, ANAN-100D).
I'm hoping Flex can improve in the following areas going forward (I'm being very picky here, but this radio has SO much potential):
1. eliminate T/R pop in rx audio on trailing edge of keyed cw message (N1MM to Winkey). This pop is heard regardless of whether using PTT MOX or break-in for T/R switching and regardless of delay setting
2. eliminate T/R rx recovery delay with slow/med AGC (as if AGC was recovering from sidetone); the rx should recover from T/R immediately at full gain (it does so with fast AGC)
3. support cw PTT MOX even with Break-in enabled – many contesters use a mix of PTT MOX on computer generated keying and break-in for a paddle; this is supported in the Orion, K3 and ANAN-100D
4. provide lower minimum sidetone level - even at zero it's louder than many of us like to set it (i.e., just audible) when running
5. FlexControl knob tuning rate is too slow at 10Hz step. Either provide a higher pulse rate encoder option or add 25Hz step tuning rate option (50Hz step is too coarse in cw)
6. add provision for reverse cw mode
7. provide for custom filter presets
8. provide for filter slope adjustment
Thanks to Flex engineering for an amazing product and for listening!
73, Barry N1EU