Posts by DL5CN

    Hallo,

    CN0417.
    There are differences between Rev B and C. My board (RevC) shows more components U2 and U3 on the backside. My idea is to use the enable Pin2 of the ADL5606 to reduce standby current. The AD-Documents "Design-Support" show Rev B. No infos for Rev C.
    In Rev B Pin 2 is grounded, very clear. Not so in Rev C.
    May be, the circuit to use the enable function is there already but I can not use it without any info about U2 und U3. I think it is difficult to find the right person at AD which can help. I will try parallel.
    I am pretty sure, there is a chance to switch the amp on and off. It is designed for mobile communication with fast time slot operation.

    Does anybody have infos about Rev C? Circuit or layout?

    Thanks in advance

    73s Andreas

    Hallo Oms,

    please remember, any infomation about power should be combined with attention to linearity. One can watch the transmit Signal with the Pluto itself. Use a dummy load and/or directional couplers with the right attenuation and look to the spectrum. The Console in combination with the Pluto gives a rather clean two tone signal with 0dBm PEP. This all is possible without a spectrum analyzer.
    At least the transponder will show if the transmitted signal is ok. From my point of view there is a great general improvement compared to the beginning more than a year ago. Don't forget the equalizer and the compressor.

    The goal must be to find a transmitter chain without unneccessary intermodulation. The Pluto followed by the CN0417 delivers +20dBm
    (100mW) with good linearity.
    @Oliver: Why don't you stick all the attenuators together and place it behind the last amp? With 36dB of gain of a two tone signal there is no danger for the attenuators. From 0 dBm of the Pluto you achieve 36dBm PEP (4 Watts PEP), the 2 W dummy load will withstand it keeping the transmission short. I would try to bring an damped signal back to the receiver to control intermodulation.

    73s
    Andreas

    Hallo,

    wir sind uns doch alle einig, daß der Empfang des Transpondergrundrauschens, wenn es denn deutlich über dem des LNB
    liegt, keine weitere Verbesserung benötigt? Das bedeutet bei den gängigen LNBs einen Mindestgewinn, den ich jetzt mal salopp
    als Spiegelgröße (z.B. 80cm) bezeichne. Korrekte Montage und Polarisation vorausgesetzt. Damit ist der empfangbare Signal-Rauschabstand der Benutzer definiert und nur noch von deren Sendeleistung abhängig, das bedarf eigentlich keiner weiteren Erwähnung.
    Daher ist die Frage nach der Art einer Gewinnerhöhung nach Veränderung des Koppelstiftes in der Tat interessant.
    Welcher Art ZF-Rx ist das und wie äußern sich 5 dB Gewinn durch die Filterung der 739,xxx ZF ?

    danke
    73

    Andreas

    Hallo,

    I can confirm, the Maximum LNBs include DROs.
    What to do? Send it back or keep the lenses?

    I added a patch to a Megasat Twin Daivolo. The Waveguide is nearly the same like the rockets. This could be an alternative.


    The Horn isn't very deep. It can be cutted with a lathe. Take care not to get in trouble with the cutter holder.
    Then stick the waveguide to a wood core for further work.

    No idea how the case will look like. And how to mount it. Depends on the dish and the LNB holder.

    I didn't expect a cylindrical wave guide. If there will be further production, wie don't need the rockets anymore.

    73
    Andreas

    Hallo,

    Mike, fully agree. There are more hints to stabilize the system. Pluto must be modified because of EMV too. I grounded the connectors to a cupper plated board below. Beside grounding there is more mechanical stability to the connectors. Take care to power supply and USB-to Ethernet -Adapter also.
    73s
    Andreas

    Hallo,

    the Console runs well, operating the Pluto via Ethernet. It seems to be difficult to handle much USB_Traffic. Don't use internal sound systems especially in case of Laptops. Sometimes it is difficult to configure.
    My recommendation is a simple small external sound card (for example Logilink 7.1 Surround). Deactivate the internal system. Look carefully to the Win_setups to be sure the sound system is configured correct.
    I don't think, the PC_performance is very important. Take a look to the system and check if all the drivers work correct.

    Yellow flags in the hardware manager require your attention.

    Please use the smallest bandwith possible. More gives more data....

    Please avoid unessecary back ground programs like scanners, newsreaders and all that crazy stuff blocking cpu_capacity.
    My SDR-Radios (Hermes, Red PItaya and Pluto) are running with WIN10 and are not permanently connected to the internet. Switch off all the "home calls" using a program named "shutup". Follow the recommendations.
    Try to keep the PC clear and fast and don't use it for the daily work like emails, surfing and so on.

    Single ITX-12V boards (DN2800MT4) from MITAC give enough performave, have a flash modul as harddisk and it is easy to integrate it together with the radio components. An example can be seen at my qrz page.

    73s
    Andreas

    Hallo,
    with some experience, my favourit LNB is a rocket style with a lense. Because the cylindical waveguide fits with a patch feed easily. It is shown in some threads earlier.
    Its seems like the Red Eagle Black Buster Single LNB or similar is not avalaible anymore. What a pity. The contacted dealers tell me, no further production. And they do not know, is there a PLL in the actual offered LNBs.
    I am looking for information to rocket style LNBs with PLL. Not for me but as recommendation. Hints are welcome.
    Thanks
    73s
    Andreas

    Hallo,

    I started with a LimeSDR Mini last year in early spring. At this time, the Console did'nt support Plutoboards.
    USB3.0 requires fast PCs and will in some cases not work with older hardware. USB3.0 cablelength ist limitted.

    Meanwhile things changed. The Console gives full support to Adalm Pluto. The biggest advantage is to control the Pluto via Ethernet. It can be integrated in home networks or direct coupled to a host. No limits in cablelength beside the usual Ethernet restrictions.
    With some mods, the Pluto is strongly recommended from my point of view. I found a way to send PTT-information via Ethernet. The Pluto and the amp can be placed closed to the dish.
    Many friends did this in this way and they are lucky. No matter, if there are 0 or 3 dBm Level. The following cascaded amps must be selected carefully for linear operation with Lime or Pluto.
    The actual release of SDR Console gives very comfortable use of QO-100.
    I take the chance to say again, Simon's work is highly appreciated and has my fully respect.

    Finally, the choice is clear?
    Ordering Pluto at digikey should be done together with CN0417 (Analog Devices Amp behind the Pluto)
    and a better 40 MHz TCXO (digikey number is 535-14661-1-ND).
    I did a little script in German showing much more details how to get on air with a Pluto. I f someone wants to get it, write me an email.

    73s
    Andreas

    Hallo,

    for those who like to control their amplifiers idle current, my idea is to send a PTT-Signal via Ethernet to the Radio which can be placed far away (Pluto and amplifier) closed to the dish. To avoid confusion, the PTT-Signal is switching the amplifier to transmit. For this special solution the Pluto is not involved.
    PoE-Adapters gives Ethernet and two independend lines for a very low price. The PoE-Plugs can be removed or changed (in my shack to Cinch).



    The PTT-Signal at the PC-Side is generated with a USB-Relay. The Relay is supported by the Console if it is conform with HID-Standard.

    I just tested the adapters, works nice. It is possible to use a PTT-Signal from GPIO-Ports of the Pluto also but there is a delay of about 800 ms switching on and off.

    Have fun with fluently SSB-Speaking.

    73s
    Andreas DL5CN

    Hallo,

    wo findet man denn ein Foto der PAs?
    Und wie sieht es mit der Linearität aus? Leistungsangaben ohne Intermodulationsabstände sind wenig aussagekräftig.
    Das gilt für den BU500 übrigens auch.

    73
    Andreas

    Hallo,

    bitte in meinen Beitrag Nummer 7 hier im Diskussionsfaden schauen. Die Dips kann/muss man abgleichen.
    Das geht mit dielektrischen Plättchen, zwischen Reflektor und Patch. Dabei verschieben sich die beiden Dips nach unten.
    D.h. die originalen Maße sind schon korrekt. Ein bißchen wie ein Puzzle, der NWT4K zusammen mit der Brücke vom Andreas,
    DL4JAL, (siehe letzten FA) gestattet die S11-Betrachtung. Die Einflüsse von Kabeln beachten.
    73
    Andreas

    Hallo,

    the LimeSDR Mini has three thermal sources. To reduce thermal drift, the board is mounted upside down on a big plate of aluminium. The plate has the same size as the Laptop I use for portable operation. All the other components like USB-Hub, sound card, power supply, USB-Relay, PTT-Interface, PA and some connectors are mounted on this plate too. The thermal capacity of the plate helps to avoid fast change of the LimeSDRs TCXO. Between the Lime and the Aliminium plate there are a little milled peace of aluminium and silicon thermal pads. This is for levelling the different hights of the Lime-Chips and thermal coupling.
    At least, the TX-Frequency changes a bit with the environmental temperature beeing outside. Adjusting this once at the beginning of a session with XIT of the Console will give sufficient stability.



    The upper cover, normal carrying the Laptop is removed. The lower floor gives room for extensions. At present there is a 12V-power supply for the Laptop. The complete radio is running with 12V too.



    Here is the LimeSDR Mini mounted upside down. No need for a fan. The hight of the board is fitting with the USB-Hub left.

    73s
    Andreas

    Hallo,

    if someone is talking about the occupied bandwith, don't forget the intermodulation distortion. This is (some times) much more than 2,8 KHz.
    Use the audio equalizer to correct the frequency response. Individual voices require adjustment. A frequency response of 6 dB per octave is recommended in the literature. Most of the signals show too much level closed to the carrier. The goal is a well balanced spectrum inside the SSB-Filter.

    Use the compression to reduce signal dynamic. Even with low signal to noise it is important to have a level control.
    Peak clipping avoids overdriving amplifiers and reduces Intermodulation.
    All this is possible with the SDR Console what I - and so much more users appreciate very much.....

    73s
    Andreas

    Hallo Mike,
    I think, there is no need for copper. The idle current is around 800 mA. With rf the current reaches approx. 5 A. If one interrupt the supply to the idle current circuit, the standby mode is easy. This can be done disconnecting the copper on the lower left side below the huge electrolyt capacity C136. Then the idle current is off complete. The PTT-switch on can be done with electronic, there are a few Milliamps flowing only. I like "high side switches" for example BTS4140 from Infineon. They have a control input pin. Pulling it to GND, the input supply is given to the output pin.


    With the normal doherty operating no dangerous heating can be seen. The transistors are not at the same mechanical hight as the print. It's recommend to resolder before mounting. With a good thermal connection like "Artic Silver" or similar, save operation with an aluminium cooler is possible. With driving power around one to two watts, the output is more than enough for NB-operation with very good linearity.
    73s
    Andreas

    Hallo,
    mit dielektrischem Material zwischen Patch und Reflektor kann man die beiden Dips, die sich bei einem Patch ergeben
    sollen, abgleichen.




    Ich hatte leider nur 0,5mm Material und damit sind die beiden Resonanzen zu hoch. Das Ganze funktioniert wie ein Puzzle.

    Im S11 Plot ist die Verschiebung nach unten, symmetrisch um die Betriebsfrequnz herum, zu sehen. Das dieeletrische Material sind eilig zugeschnittene FR4-Stückchen.



    73
    Andreas

    Hallo,

    I did a new Dualfeed-System for a friend with some new ideas. Mill a brass tube. There is no need to reduce the outer diameter of the rocket but removing the lense flange. Clean it with sand paper. The brass tube has a new flange to carry the lense. All three parts can be sticked together. No loss in LNB because all is original.



    Solder the patch and the reflector disk to the tube. One can mill 3mm (plus copper thickness) shoulder to the tube to get the right distance between the patch and reflector. Don't forget to drill the "feed hole" when both parts are fixed flat together with a srew before soldering. In this case, the reflector disk hole has a reduced diameter to stay on the shoulder.




    This is the ready LNB. It gives a compact unit and can be mounted with the most dish equipment.



    If the upper bracket gives no room for the S-Band-Cable, take a metal bracket. The picture shows my own feed with heavy Cellflex cable. The transition to SMA-Surplus-Cable is fixed with an alu bracket


    By the way, rockets with 25 MHz TCXOs are extremly stable. No fast changes in the final frequency can be observed like it was with 27MHz from Connor Whinfiled mounted in Octagons.

    There is only little change with outside temperature which can be easily regulated with SDR Console.


    Many Thanks to Simon in this way ! He did a great job all over the year. We appreciate this very much.


    Finally, the feed is a compact unit. It can easily be changed and compared with other antennas, probably a helix.

    73s, have fun
    Happy New Year to all "Helians"

    Andreas