After previous years (since inception of IOTA) of hard effort (dxpedition to EU123) and then having the door slammed by the RSGB on any effort during COVID in 2021 (as I was on holiday in EU5 at my own holiday accommodation), I decided not to bother with the contest this year. Instead I would use it test out Flexradio SSDR multiflex capability. For the Flexradio 6300, this allows 2 ops to have apparently separate receivers (using the 2 available slices of the 6300) and also share the transmitter of the 6300.
I used a laptop running N1MM+ and connected to the 6300 using Smart CAT for frequency and mode for the log and also to emulate a winkey for CW transmission of N1MM+ macro messages. I also had a Flexradio Maestro, so I connected that to the 6300 so I didn't need to run SSDR on the laptop (to keep the load on the laptop to a minimum).
My fellow tester (MM0GBK) used a laptop running N1MM+, but this time used Smart CAT and SSDR software as his interface to the 6300.
Both stations were located in the same room and were connected to the 6300 via the same ethernet switch. I was using CW and MM0GBK/P was using SSB
Multiflex is automatically invoked by the 6300 when detecting multiple connections (6300 is capable of having 2 connections: in this case Maestro hardware and SSDR software running on a laptop). Transmission capability is allowed on a first come first served basis and the other connected user is 'locked out' whilst the transmission is in progress.
This type of operation is best suited to S&P which allows both users to search for unworked stations and then take turns at working them sharing the same transmitter. This worked perfectly during the contest and seemed to handle the occasional time we would both try to transmit at the same time (no power out indicated to the loser). Running leads to the other user having too little time between transmissions to find stations.
All in all zero lock ups were observed by both users however, cw generation via Smart CAT emulator wasn't well timed with occasional sidetone audio aberrations (not sure whether they were transmitted or not) even though an Intel i5 8 core was in charge without SSDR running (Maestro doing the heavy lifting). This led to me to think I'd be better off with a real winkey or some other keying method.
I would not recommend Flexradio, SSDR or multiflex to any serious contester due to rx latency, inaccurate cw generation, cost, hardware reliability, complexity, etc, etc, etc. However interesting the concept, it just took too long for the company to get it right and as a result has lost all momentum and user base (especially in CW contesting).
Currently the majority of Flexradio users are digital and SSB mode users. CW has never been implemented well, with the company mainly listening to the American full break-in casual ops instead of world wide serious contesters. Casual CW ops may like the Flexradio offering, but this should not be confused with serious contesting equipment.