Posts by G8UGD

Thanks for the file Elmar.

Do not forget to change the geostationary beacon frequency in SDR-Console, or get confused as I did for a good 10 minutes.

Adrian

Pete, can you use/build a very simple style diode detector on a 50 Ohm termination to measure volts with a DVM. should be able to give you relative measurements?

Quote from RN3ARU

Many listen and wait for new stations.

Perhaps this is the problem, people only wanting stations in countries they have not heard of for DX. Not wanting to make friends and chat CW or SSB.

QO-100 is a repeater and once you have a system to gain access you can converse to almost a third of the world. As said on the A71A Wideband beacon "To receive us clearly and we will receive you 9 by 9"?

There are digital modes, such as RTTY, FT8 and others, slow scan TV, digital voice, spectrum painting,

The satellite could be used to arrange skeds and/or talkback for the amateur bands from HF to GHz, arranging long range tests etc. It has coverage of approx 100 degrees of the globe which makes it the best repeater we have other then the internet. There was talk of it providing limited broadband access to some parts of the world. It is apparently 1 year old and perhaps the novelty is wearing off.

I admit I can not converse in CW my skills are lacking in that area, also I need to build back my narrow band setup again.

Have fun, be safe.

Adrian

This has been done once before on the SSB section of the QO-100 band. There was an 144 MHz uplink and downlink transverter (I forget the correct name). Great care needs to be taken both in design and also in time use, if memory serves me correctly it was left on during a contest weekend when 144 MHz signals were getting in and coming out on QO-100 causing confusion.

To be effective the HF receiver will need to be sensitive, selective and low noise otherwise the noise floor will be lifted in the corresponding segment on QO-100, so constant monitoring or some active feedback of the uplink frequency to reduce gain to minimise this, a sort of AGC.

One issue is that with HF and band openings/time of day, the signals on CW can come from anywhere in the world and not just from a local country, so unless all radio amateurs were to know about it how would it be managed, what of regulations, do all countries regulatory bodies allow rebroadcast etc.

How would you stop a couple of hams say in the states, having a CW natter between themselves ending up on the satellite uplink completely unaware of it. It could be done but you need a way of having some form of input protection such as CTCSS or DCS signal used on FM repeaters, 'color' codes etc as used in digital what could you use for a CW signal that would be easy to implement on existing ham gear?

Perhaps reduce the proposed 20KHz down to just a few KHz to reduce the impact etc. These are all things that could be considered.

Then again these are all just my musings thinking aloud, I have no influence over other users or Amsat-DL or Quatar. It could be an interesting concept if all minds worked together and it is done correctly, could lead to complete chaos if done wrong.

Adrian

I did three plates recently, 2 for local hams and one as a spare for myself, this is the one I did as a spare as I have a spare board.

In case you wonder, I make two index marks when doing any machining, one is a 2mm hole at X=5mm and Y=5mm and a 3mm end mill hole at X=10mm Y=5mm. These to help me when I change from a 2mm drill to 3mm end cutter without a proper tool change setup I loose index, but it seems to work out for me just takes time. I would still like to get feedback from other CNC'ers!

Hello Peter & Heiner,

Thanks for the responses, I was wondering about it as there was little news I could find on the subject. I was also wondering to myself if the reduction in bandwidth would also have a corresponding reduction in power consumption of the amateur side of the satellite, I guess it must have some effect when on for 24 hours a day. Also the uplink would not need as much punch to get a signal to the same MER etc. Overall a reduction in required power levels if only minor. Is there any advance notice of the revised band plan out there as I can only guess that software for Minitiouner, Pluto and probably others would need to be revised?

Anyway doing a good job.

Adrian

Peter; I was wondering if this change is still on the cards or if it has been cancelled?

Adrian

What is on the underside of the pcb?

My best guess at the bias circuit is in another thread here:- https://forum.amsat-dl.org/index.php?thread/2906-can-i-just-ask-about-a-pa-from-bisonelectronics/&postID=11857#post11857

Post #83 Perhaps that may help fault find.

I have the model that purports to go to 8GHz and as supplied was an absolute pile of crap, When taken to an OP that has the correct gear, at 2.4GHz it was found to be +5dB high at the top end of it's range which is basically around -5dBm

As you went further down the dBm range I found the error crept higher. The chips on the processor and display board have been scraped to stop one identifying them but I suspect they would be Atmel. Some have reused the detector board at the bottom and done on one of their own processors with A2D on them.

I did find what I think to be an error on the sampler board where the output resistors were 100 Ohms instead of what I think should be at 10K, the output is basically voltage doubled, with no signal input being around 4.1 Volts going down towards the lower voltage as one puts more signal in.

I do wonder if a simple diode detector on the output of a 30dB directional coupler would give better results. I have modified mine changing the output resistors and use of a variable pot so that it tracks within 0.5dB from a range of -40input to -10 input at best, not fantastic, but the best I could get. Unless someone can rehash the software in these personnel experience says they are not worth it.

Sorry if this is not what anyone wants to hear, but just based on my experience.

Adrian

I thought the free updates had gone? But I stand corrected as i see there is still a way to do it. I doubt my old 2009 machine would survive such a transition, unless someone with a dell Optiplex 780 can tell me different.

Thanks for the reminder Heiner.

Adrian

I have done an update to the dxf file, I realized that the previous DXF file (in the zip) would not show the actual image I had been using.

I have done a dxf for a single PA, watch out for the holes (points for the cover) when you buy the PA as a Single you could get either the left, or, right-hand side of the cover and the holes are very different.

So anyway here is the single PA dxf with an image file in a zip. Un-zip into a folder and then open the dxf from that folder and I hope you will also see the image file. Please let me know if you do. If it works I will then try to amend the original file I uploaded.

Also, I need some feedback if you use the file as to it's accuracy. I used a picture of the image to determine where the points are for drilling. I drilled 2mm holes for 2.5mm screws. The PA cover can go bigger and I drilled out and used M4 screws for that.

If anyone has CNC facilities please mill out first on some MDF or other suitable material before you build your PA. Check the accuracy of everything. My machine is not an accurate one and I am getting small errors, not enough to cause me any issues but I do not know if the errors are in the drawing or my machine, I have normal lead-screws and not ball-screws on the mill and therefore have backlash errors I can not correct.

Many thanks and feedback appreciated to know if it works for others.

Adrian

Ich habe die Änderungen in meinem Windows 7 x64 mit OBS ausprobiert und alles scheint in Ordnung zu sein. Können Sie die Optionen für den Ausgabemodus von "Einfach" auf "Erweitert" ändern und die anderen Optionen wie angegeben ausprobieren?

Hello Manfred;

You say FEC3/4 in the text above but have 2/3 set in OBS stream command, which matches you TS bit rate of 440.3 and your first post.

I have tried the changes in my Windows 7 x64 with OBS and all seems to be OK. Can you change the options for Output Mode from simple to advanced and try the other options as I have them listed?

I have tried a UDP stream via from OBS and even OBS > ffmpeg and it seemed to last for around 30 seconds with minimal delay, but then stops, so I thought there may be checking for the H264/H265 box? My reasoning was I got something like a 9 second latency with the rtmp stream and 4.5 seconds udp. Then I changed a few of the settings in OBS and got rtmp down to 5 seconds which will do me for the time being. I think there are many variables outside of the Pluto to consider. It is not easy for me but I am trying to understand the scripts within Pluto to gain better understanding.

Adrian

The ,nocalib,600,32, The 32 at the end is for the Pluto to reduce the audio bitrate down further to 32kbps, give that a try and see if it helps, but it may make it worse if the audio is delayed.

I will try OBS in Windows 7 and see what works for me some time Sunday.

Adrian

Ich habe vergessen zu fragen, ob Sie Windows oder Linux für OBS verwenden, da Windows anscheinend nur ein Minimum von 64 Kbit / s für Audio zulässt, wobei Linux auf 32 Kbit / s Audio herunterfällt. Stellen Sie sicher, dass alle Audiospuren auf Minimum eingestellt sind.

Es ist ein Ausgangspunkt für mich, und ich arbeite daran und beginne, Dinge wie Auflösung usw. voranzutreiben. Hinweis: Ich arbeite auch nur mit einer Bildrate von 15 Bildern pro Sekunde.

I forgot to ask if you were using Windows or Linux for OBS, as windows seems to only allow a minimum of 64Kbps for audio, where Linux will drop down to 32Kbps audio in each case make sure that all the audio tracks are set to minimum.

It's a starting point for me and I work from these and start to push things such as resolutiion etc. Note I am also just running at a frame rate of 15FPS.

Hallo Manfred;

Ich fange an, ein sehr ähnliches System zu verwenden, abgesehen von einem FEC von 3/5 und wahrscheinlich einem langsameren PC, bei dem es sich um einen Core-2 Quad-Prozessor mit 3 GHz handelt

Ich habe Screenshots meiner Einrichtung gemacht, damit Sie diese für 333KS ausprobieren können. Ich hoffe, es hilft.

Ändern Sie Ihre IP in Ihre eigene IP, wenn über den USB-Port wahrscheinlich 192.168.2.1.

Dies basiert auf QPSK bei 333 3 / 5FEC mit einer TS Net-Bitrate von 396 kbit / s.

Ich hoffe, es hilft.

Adrian

Hello Manfred;

I am starting to use a very similar system, in fact apart from having a FEC of 3/5 and probably a slower PC, which is Core-2 Quad processor at 3GHz

I have taken screen shots of my set-up so you can have a go with these for 333KS. I hope it helps.

Change your IP to your own IP, if through the USB port probably 192.168.2.1.

This is based on QPSK at 333 3/5FEC which has a TS Net bitrate of 396.kbps.

I hope it helps.

Adrian

I must admit to preferring some slightly bigger units, but not for receiver side I am not that clever to design boards.

I built two of these style ID filters for transmit, one is directly out of the SDR unit and another after the pre-drivers just before the main PA, the idea is to reduce any spurs from the SDR or spurs from the pre-driver stages up to about 2 watts.

On the trace I had approx 0.3/0.4 dB insertion loss and the divisions were 50 MHz per division horizontal and 10dB per division vertical.

Adrian

Hello Manfred thanks for the response and I did see a nice signal from you on the Sat.

10:59 G8UGD Adrian DK5FA a nice MER of 7.1 D4 on a 1.05m dish

500KS is an odd thing as it is not mentioned in the band plan at all, it goes 2MS, 1MS, 333KS, 250KS and then 125KS, then again neither are the others 66KS 50 KS and 33KS.

Software like MiniTioune Keeps 500KS on receive below 10,497 MHz, but many will consider 500KS as Narrow band as it is not 2MS, and I believe considered Reduced bandwidth when used on 146MHz Operation.

Wish all the best for the New year to you and your family.

Adrian

DK5FA

Hallo Manfred; Ich hoffe, es macht dir nichts aus, wenn ich frage, was blöde Fragen sein können. Was haben Sie in Bezug auf die Leistung einiger der Übertragungen als bedenklich empfunden, da ich der Meinung bin, dass Google Translate keine sehr gute Arbeit geleistet hat, der ich folgen sollte? War es nur die Bandbreitenübertragung oder eine über 500KS Abtastrate, die höher war als das Beacon? Oder waren es weite Übertragungen im reduzierten Bandbreitenbereich?

Ich denke, es gibt viel Verwirrung bei den Leistungsstufen.

Übertragungsleistung
Alle Uplink-Übertragungen sollten möglichst wenig Strom verbrauchen. Keine Übertragung sollte ein Downlink-Signal mit einer höheren Leistungsdichte als der Beacon haben - der webbasierte Spektrum-Monitor ermöglicht es Benutzern, ihre Uplink-Leistung einzustellen, um dies zu erreichen.

Aber im nächsten Abschnitt heißt es:
Benutzer sollten mit DVB-S2-Modi höherer Ordnung mit niedrigeren Symbolraten experimentieren (z. B. 333 KS 32APSK), um Bandbreite für andere Benutzer zu sparen. Dies würde viel höhere MER's als das der Bake erfordern.

Ich glaube, der zu beachtende Ausdruck ist "Leistungsdichte", in meiner vereinfachten Denkweise "Leistung x Bandbreite". Also nochmal mit einer sehr vereinfachten Ansicht. Wenn Sie mit einer angezeigten Leistung von 8 dB über 2,7 MHz Bandbreite bei einer 2000-SR-Rate von 21,6 dBMHz senden. Also also ein 333-Signal; welche bandbreite von 0,45 mhz kann ein angezeigtes db von 21,6 / 0,450 = 48db haben und hat dann die gleiche leistungsdichte wie das 2ms signal? Dies würde natürlich auch für 32APSK nie benötigt werden.
Ich kann mich natürlich in der Interpretation irren, würde mich aber freuen, den richtigen Satz zu finden?

Der Wortlaut dessen, was übertragen werden kann, würde jedes Video über 10 Minuten hinweg entfernen, es sei denn, es ist AMSAT-Geschäft und würde uns grundsätzlich zu Video-QSOs und Video-Streams unserer eigenen Stationen führen. Ich habe einmal die Verwendung von Cartoons und Holiday-Werbevideos in Frage gestellt, da ich dachte, dass es sich um Werbematerial handelt, aber mir wurde gesagt, dass es sich um hochwertige Quellen handelt, die zum Testen verwendet werden!

Ich gebe zu, dass ich es genieße, Landschaften aus der ganzen Welt zu sehen, da es für mich von Interesse ist, Orte zu sehen, an denen ich noch nicht war und die ein oder andere Video mit Szenen aus dem Vereinigten Königreich gesendet habe, und ich wäre enttäuscht, wenn das nur als klassifiziert werden könnte allgemeines Interesse für andere Amateure sollte als zu beanstanden angesehen werden.

Ich mag die Amsat.dl-Site für Themen wie diese, da das BATC-Forum nur technisch zu sein scheint.

Alle Google Übersetzer entschuldigen.

Grüße

Adrian

Hello Manfred; I hope you do not mind me asking what may be stupid questions. What did you find objectionable with regards the power of some of the transmissions, as I do not think Google translate did a very good job for me to follow. Was it all bandwidth transmissions or ones over 500KS sample rate that was higher then the beacon? Or was it wide transmissions in the reduced bandwidth section?

I think there is a lot of confusion on power levels.

Transmission Power
All uplink transmissions should use the minimum power possible. No transmissions should have a downlink signal with a higher power density than the Beacon – the web-based spectrum monitor will enable users to set their uplink power to achieve this.

But it goes on in the next section to say:-
Users are encouraged to experiment with higher-order DVB-S2 modes at lower symbol rates (for example 333 KS 32APSK) to conserve bandwidth for other users. This would need greatly higher MER's then that of the beacon.

I believe, the phrase to note is 'power density', in my simplified way of thinking 'power x bandwidth'. So, again with a very simplified view. If you are transmitting with an indicated displayed power of 8dB over 2.7 Mhz bandwidth for a 2000SR rate = 21.6dBMHz. So therefore a 333 signal; which has a bandwidth of 0.45MHz can have a displayed dB of 21.6/0.450 = 48dB and will then have the same power density as the 2MS signal? This would never be needed obviously even for 32APSK.
I may be wrong on the interpretation of course, but would be happy to discover the correct phrase?

The wording of what can be transmitted would remove any video over 10 minutes unless it is AMSAT business and would basicically lead us to video QSO's and video streams of our own stations. I did question at one time the use of cartoons and Holiday promotional videos as I thought they would be copywright material, but was told they are high quality sources used for testing!

I will admit that I enjoy watching sceanery from around the world as it is of interest to me to see places I have not visted and have sent the odd video of scenary from around the UK and I would be discuranged if what may be only classed as general interest to others amateurs should be considered as objectionable.

Just some of my ramblings, I like the Amsat.dl site for topics like these as the BATC forum seems to be technical only.

All Google translate sorry.

Regards

Adrian