I own an Omni D-B. My understanding is it differs from an Omni C in that the
latter will function on 12 & 30M if the correct crystals are installed, the
Omni D-B receives 30M but required a modification kit to transmit on 30M.
Neither can function properly on 17M, though evidently TT claimed otherwise.
The audio and if filters on the Omni D-B were cascaded, those for the Omni C
are selected individually.
Other than these differences, ( and a few years age ) the two are identical, so
many of the boards would interchange?
73, Curt KB5JO
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