I'm looking for a receiver that can receive in AM, FM, USB, or LSB mode, for frequencies at least as high as 1.4204057517667 GHz (this very specific frequency is the 21cm hydrogen radio spectral line, typically used in radio astronomy). Of all the modes though, the one that's most important is USB. If I tune to 1kHz below this frequency while it's in USB mode, if there is hydrogen gas near the receiver's antenna, I should hear a 1kHz tone. Is there an off-the-shelf receiver I can buy that will tune to frequencies that high, and be able to listen in USB mode? I know ICom has some receivers that can tune that high, but they are limited to AM and FM reception in those bands, and USB reception is only permitted in bands below 1.3 GHz. I have an ICom PCR-1000 (computer controlled receiver) and it can use all modes in all bands, but the highest frequency it can receive is 1.299999999 GHz (just short of 1.3GHz). There are other receivers that ICom offers that can tune up above 1.3GHz, but in those higher bands, USB and LSB reception is disabled.
Can anybody here recommend a receiver that is being sold commercially (no custom equipment, no modified equipment) that can tune in to the hydrogen 21cm emission, while in USB mode? And if so, what would it cost?