----- Original Message -----
From: "Tom Rauch" <w8ji@contesting.com>
> ...and therein lies the problem that stopped us from using
> the radio as we hoped.
>
> Even 80-85dB close spaced IM3 DR is enough here if the
> receiver only has to handle a window a few kHz wide, but the
> problem is the entire 160 band is just packed full of strong
> stations during a contest. While a regular superheterodyne
> receiver only has to handle things in a couple stages that
> can easily be made very stout before hitting a filter, a
> direct conversion receiver has to handle the entire mess.
> There is a huge increase in overall signal power in that
> entire wide window.
>
> While the FT1000MP MK V with preamp on (-135dBm sensitivity)
> had a blocking DR of around 140 dB at wide spacing and
> around 135 dB at 20kHz spacing, the SDR radio only had ~
> 99dB blocking at any spacing (with preamp set to essentially
> the same sensitivity as the Yaesu). Wide-spaced dynamics
> that were already marginal decreased by 30 to 40dB, and
> meant the radio could not be used for what we were trying to
> do.
>
This thread puzzled me as it seemed that Tom and Bob were
vehemently agreeing with each other. Let me explain:
a) What did Tom W8JI say when asked what was so bad
about the SDR-1000?
"It has essentially the same dynamic range regardless
of tone spacing"
b) What did Bob N4HY say when asked what was so great
about the SDR-1000?
"It has essentially the same dynamic range regardless
of tone spacing"
73 Mike, W4EF......................................
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