[Skimmertalk] RedPitaya 125-10 vs 125-14

Bob Wilson, N6TV n6tv at arrl.net
Fri Nov 24 08:55:49 EST 2017


On Fri, Nov 24, 2017 at 3:50 AM, Paul <gw8izr at gmail.com> wrote:

> From your list Bob and for technical completion, it is quite a lot less
> sensitive than the QS1R even with the matching transformer, certainly here
> I would need an external preamp or active band preselector, this would
> further degrade the already worse large signal handling capability. The
> return loss at the input will make it more difficult to match to external
> filters.
>

I'm not following you here.  We have:

50 ohm antenna -> 50 ohm lowpass filter (opt) -> 50 ohm pre-amp -> 1:14
transformer -> High impedance input of Red Pitaya

So where is the high SWR / high return loss?  The transformer board is
located right on the input connector.

This is the first time anyone has reported the the QS1R is "quite a lot"
more sensitive than the Red Pitaya.  What frequencies are we talking
about?  How was the measurement made?  Both the QS1R and the Red Pitaya
benefit from external filtering and pre-amps in the same way.

Pretty much what we should expect when comparing a $750 receiver with $300
> piece of test equipment. (or whatever the current prices are)
>

Well, another advantage of the Red Pitaya is that it *can also* do many
other things:  dual trace oscilloscope, dual channel signal generator,
Vector Network Analyzer) VNA, etc.  See http://bazaar.redpitaya.com/ .

73,
Bob, N6TV


More information about the Skimmertalk mailing list