Juan,
I have not seen any SDR transceivers that operate at VHF/UHF yet.
One reason is that the Analog to Digital Converter (ADC) technology for direct conversion is really not yet fast enough to handle those frequencies (remember Nyquist sampling theorem N (or frequency) x 2) as minimum. It is easier to use a transverter to convert the signal down to HF and use existing SDR radios.
"Lossy Traps, Oh my!"
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