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LNA / preamp is an unpopular topic of the portable SAT discourse. Noise figure (NF) is assumed to be low due to absence of long cables. But what if NF of the system inherently is not top tier? Any benefit in using LNA with FT-817 & FT-818? 🧵
#hamradio #amsat #amateurradio #hamr
#hamradio #amsat #amateurradio #hamr
NF & MDS are determined by the quality of the signal chain and the venerable FT-818 is not a star in that department. Under exact same conditions (antenna, cable etc) a very weak signal readable from IC9700 would not be copyable from FT-818. 2/7
#hamradio #amsat #hamr
#hamradio #amsat #hamr
The comparison of NF & MDS of IC705, IC9700 and FT-818 assumes favourable IMD performance of the FT-818 with a 500 Hz filter. In the field this is rarely true and even less so with a passband of 3 or 2.7 kHz in SSB. 3/7
#hamradio #amsat #amateurradio #hamr
#hamradio #amsat #amateurradio #hamr
