[Skimmertalk] Red Pitaya 1:14 impedance transformator + SV1AFN pre-amplifier
ve7cc at shaw.ca
Mon Oct 23 04:02:12 EDT 2017
I have found an easy way to accurately measure exact s/n ratio changes in any skimmer system. This only requirement is a having a beacon or other reliable signal within ground wave range. I have a beacon on 10 meters that I use. Simply see what the skimmer is giving for a s/n report for this signal. Then make your changes such as adding a 14:1 transformer, a pre-amp, or an inline filter etc. After each change, wait a while and see what the new s/n report is. The difference between the new and old reports is the exact difference caused by whatever you did. This method is accurate, repeatable, and requires no test equipment.
----- Original Message -----
From: DD5XX (Saki) <dd5xx at web.de>
To: skimmertalk at contesting.com
Sent: Mon, 23 Oct 2017 01:15:09 -0600 (MDT)
Subject: Re: [Skimmertalk] Red Pitaya 1:14 impedance transformator + SV1AFN pre-amplifier
thanks for feedback. I think I will order one from SV1AFN. I already did
send him an email with some questions yesterday. Hopefully will order
one this week. Thanks again and have a nice week.
Am 23.10.2017 um 01:32 schrieb Martin Rath:
> Hi Saki,
> I use Maki's J310 LNA in front of the red pitaya for 2 2 reasons:
> 1) additional gain. As per Maki himself the res pitaya requires an
> additional 5-10 dB amplification.
> 2) to protect the inputs: less than 2 were after i got the RP a close
> by lightning took out the AD8066 op amp. I did manage to replace don't
> want to so that all too often: Singapore gets hit by major t-storms
> over 200 days per year. Running a skimmer here is not always easy as i
> cannot always be home to unplug the antennas. I would much rather have
> to replace a J310 than the AD8066 another time.
> I'm happy with the performance. I'm still waiting for one 14:1
> transformer but it's already on the way.
> 73's Martin 9V1RM
> On Mon, 23 Oct 2017 at 00:13, DD5XX (Saki) <dd5xx at web.de
> <mailto:dd5xx at web.de>> wrote:
> Hello all,
> thanks to Bob (N6TV) I got one of those Red Pitaya impedance
> transformator 1:14. I wonder if anyone did try to add a
> pre-amplifier on
> the input and if so what is your experience ? I have heard and did
> lots of positive feedback on the pre-amplifier offered by SV1AFN
> on his
> website. I would be interested in the kit "J310 push-pull HF pre-amp
> 0.5-54MHz" (see "https://www.sv1afn.com/j310preamp.html"). Do you
> to gain some more dB performance with this combination ?
> Red Pitaya INPUT1 <---- 1:14 impedance transformator <---- SV1AFN
> Looking forward into your comments.
> Saki, DD5XX
> Skimmertalk mailing list
> Skimmertalk at contesting.com <mailto:Skimmertalk at contesting.com>
Vy 73s de DD5XX
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