Dear Joe, LF Group,
There is quite a lot of info, including schematics and measurements, on the
FT817 RX at:
http://www.ussc.com/~turner/ft817_rcv.html
This comes to the same conclusion about the LF sensitivity. It is a bit
difficult to interpret the sensitivity measurements with/without the preamp,
but the sensitivity without the preamp would appear to be about 36dB down at
100kHz compared to HF, and even worse with the preamp on. Since the same
mixer transformer is used from 100kHz to 470MHz, it would probably be
difficult to do much better with this component than Yaesu have done
already.
BTW, the QRSS10 sigs from VO1NA have been visible much of the time over the
last couple of nights here - with "O" copy for considerable periods. The
most consistent times appears to be between about 0600 and 0800 utc here.
YU7AR has been a good signal too, about S5.
Cheers, Jim Moritz
73 de M0BMU
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