I was looking for information on the 2 final amplifier modification sold by bisonelectronics. my email iw1dbf@libero.it thanks
Hallo Heiner, bin gerade dabei meine 2.Station mit dem Pluto fertig zu bauen. Wie mache ich beim Pluto die PTT Steuerung ? Möchte nach dem Zwischenverstärker die
Hallo Hans,
bei einer Stromaufnahme von nur 1A oder weniger brauchst Du bei 15m Kabellänge nicht wirklich bedenken haben. Nimm ein Kabel mir mindestens 2mm2 Kabelquerschnitt und gut ist es. Du kannst ja vor dem Transverter noch einen keramischen 10nF Kondensator und einen 1000uF Elko dranlöten. Dann kann eigentlich nichts mehr passieren.
Viele Grüße
Matthias
Hi Kurt,
this is really cool especially that you can use it together with the Minitouner.
Are you planning to support also the Airspy (R2), which is also supporting 10 MS/s ?
That would be really great as I am using Airspys here ...
Kind regards
Matthias
Hallo Martin,
Super wenn alles geklappt hat.
Da hast Du aber auch echt Pech gehabt ... so eine defekte F-Buchse ist sicherlich sehr selten ...
Viel Spass mit dem Konverter
Viele Grüße
Matthias
http://www.dd1us.de
Hallo Achim,
vielen Dank, genau und bei meinem tiefen Spiegel verliere ich schon 6dB wenn ich nur ca. 2cm aus dem Fokus bin.
Beim Optimieren auf das letzte dB war ich also schnell im Bereich von 5mm. Passt gut ...
Viele Grüße
Matthias
Hallo Kurt,
insbesondere beeinflusst das f/D des Spiegels, wie genau die Brennweite getroffen werden muss,
Bei flachen Spiegeln mit einem grossen f/D (wie die meisten sat-offset-Spiegel) ist es unkritischer,
bei tiefen Spiegeln mit kleinem f/D (wie meinem prime-focus-dish mit f/D=0.29) ist es schon kriischer.
Viele Grüße
Matthias
Hi Ribert,
you are very welcome.
Actually you can simply use the cosinus function.
Theoretically the loss at 90 degree is infinite but in the real world it is somewhere around 20dB (because the TX and RX antennas are most likely not ideally linear polarized and you might have reflections etc.).
Kind regards
Matthias
Hi Robert,
left not really as the transponder rolls off quickly.
Right maybe depending on the sensitivity of your system.
Sorry, bit I have not checked myself today the WB tpx for radar interference.
Kind regards
Matthias
Hi Robert,
of course the radar signal is not stronger than the WB beacon, which you are showing on your screenshot.
Kind regards
Matthias
Hi Robert,
interesting setup, but why did you take the route to circular polarization ?
If you use a normal linear polarized LNB and tilt it 45 degrees then you receive also both transponders.
Of course you will also loose 3dB on each transponder going that path.
Kind regards
Matthias
Hi Renaud,
the somewhat cyclic white lines are most likely from an unknown radar source. Today it is especially bad but it has been present for quite some time.
The pacman picture in the waterfall, which is transmitted cyclically, is to remind people to honor the guard band to the PSK beacon.
Kind regards
Matthias
Please note that the tube acts as a high pass filter and suppresses the 2.4 Ghz signal.
The longer the tube, the higher the suppression.
I recommend to make it not too short but for sure not as long as shown in the pic from DD4YR above, I think 6 cm is enough.
Also don't use regular silicone (smells like vinegar) to glue the copper to the LNB ... that will react with the copper
and will be a mess ...
Kind regards
Matthias
Hi 4Z4LS,
that will be nice, many thanks in advance and good luck with your interesting project.
Kind regards
Matthias
Hi 4Z4LS,
thank you for sharing your ideas.
I am not sure I understand how you can operate with that unit full-duplex.
In addition how do you plan to deal with the suppression of your local oscillator and your image frequency of the 2.4 GHz upconverter.
You will need a very high Q filter to get to an acceptable level (min 60dB suppression !?).
In receive mode I propose to switch off the driver stage and the PA as you will otherwise generate additional spurious emissions due to your frequency generation scheme.Kind regards
Matthias
Hi Thomas,
why do you think that this should not be transmitted on the NB transponder ?
I think Roland was perfectly right: the used a bandwidth of less than 2.7kHz and the transmission was in the mixed mode part of the NB transponder. From my perspective all fine.
Kind regards
Matthias
Hi Jan,
I fully agree, as long as there is no low cost VNA covering the 13cm band available which provides a Smith-chart this VNA is certainly a good choice.
Kind regards
Matthias
Yes, but as far as I know it is not supporting Smith-Charts which is IMHO a big drawback
Kind regards
Matthias
Hallo,
ich habe vor einigen Wochen gelesen, dass es bald den NanoVNA mit einem erweiterten Frequenzbereich (incl. 13cm) geben soll.
Dabei soll der Preis angeblich gleich / ähnlich wie der bisherige sein.
Also etwas wie dieser hier incl. 13cm:
Das wäre meines Erachtens dann eine interessante Lösung denn dieser Analyzer bietet auch eine Anzeige des Smith-Diagrams an.
Viele Grüße
Matthias
Luis,
this makes no sense.
A LNB which is connected to an antenne using a coaxial cable is not sensitive to any polarization.
It just takes the signals which come from the antenna, whichever polarization the antenna may have.
If you like we can take this discussion offline as it does not fit at all in this forum.
You can find my email adress on my website.
Regards
Matthias
