Most unfortunate indeed . The goals that the Sentry was seeking to achieve would be revolutionary for a "DC-Daylight" capable radio. The note posted on the CCW website simply states: "After three long years development work resulting in a working prototype we have reluctantly decided not to put the Sentry SDR transceiver into production. We realise that without a major expansion of our company would not be able to meet the demand for the transceiver or provide adequate customer support. There is also an additional legal aspect to the decision. We have had enquiries from many potential users who may not use the proposed transceiver for amateur radio use and will use it for illegal purposes or detrimental activity. Thank you for all the support and feedback given during the development of the transceiver." http://www.crosscountrywireless.net/sentry.html I suspect the regulatory/legal aspects are similar to what Flex Radio faced with the SDR-1000 and the Flex-5000/3000/1500 models that came after it. The SDR-1000 was very open in terms of where you could make that radio go. The Flex-5000/3000/1500 I/Q QSD/QSE designs all have a firmware layer in the radio hardware itself that prevents them from being used out of the ham bands without the appropriate authorization, and special firmware (same for the Flex-6000 series radios too). And no, just clipping a wire, or lifting a diode or few would "open them up" either. The hardware component lineup from what I could tell for the Sentry might not have made that kind of transmit frequency range restrictions possible (speculation on my part).