The NPR test is something I wish we had had back when Owen Garriott, W5LFL,
was preparing to take ham radio onboard the space shuttle orbiter Columbia
during the STS-9 flight.
There was no external squelch control on the radio. In fact, the squelch
was based on the average noise level on the band.
Even with about 15 of us on HT's calling him on different adjacent
frequencies as a ground test, he was able to copy everyone fine. The test
was inadequate.
Once in flight, there were so many people with such strong signals calling
him on the designated uplink frequencies, the radio thought the signal
levels it was seeing was the noise level. The radio was fooled into squelch
condition to where he made only a small fraction of the QSO's he could have
made if he had had manual control of the squelch.
dale, kg5u
>
> Well, actually, I think that contest conditions are very
> similar to the NPR test. More particularly, the NPR test is a far more
> accurate representation of what's happening on the band during a
> contest, compared to a two-tone test with just two signals on the
> band!
>
> And while some of our current receivers might look pretty
> awful, designers aren't going to work on improving them until they see
> some market interest.
>
> Thanks for all the good info, Al!
>
> -- Eric K3NA
>
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