If anyone is curious about the guts of the FDM-S2, scroll toward the middle of this link. It's a foreign language message board, but these are the first pics I've found of the S2 opened.
哈罗CQ火腿社区 - 设备 - 意大利 FDM-S2精品16Bit直采SDR FT-897挚友 - Powered by phpwind
It looks like 2 boards stacked, separated by a layer of shielding.
哈罗CQ火腿社区 - 设备 - 意大利 FDM-S2精品16Bit直采SDR FT-897挚友 - Powered by phpwind
It looks like 2 boards stacked, separated by a layer of shielding.