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 Markus,
was denkst Du über eine zeitgemäße Lösung mit einer SDR-Platine Adalm Pluto und entsprechender moderner Software?
Weil die Fragen immer wieder auftauchen, habe ich dazu einen Aufsatz mit erprobten Vorschlägen erzeugt, den ich bei Interesse gern zur Verfügung stelle.
ok, Peter, danke
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,
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,
don't edit and save the "markerfile" with EXCEL. In this case the import will not work.
73s
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
Hallo,
nice collection, it helps.
I would like to add some mechanical hints. The rocket types have no horn but a lense to correct the radiation pattern.
The original waveguide has a litte flange to fix the lense. This can be removed with a lather. The outer diameter of the waveguide must be reduced a bit and the inner diameter of the 2mm copper tube must be slightly increased, in this way that both can be sticked together smoothly. Now you can decide using a patch or a helix. Fixing the lense again, there is brass washer soldered to the copper tube.
Milling the lnb is possible when prepare a wood cone with the inner waveguide diameter.
To combine a horn type lnb with a patch is more difficult.
Part of the horn is removed. This gives a flat flange. The brass flange is fixed with 3 screws and soldered to the copper tube. The input of the copper waveguide has no pretection and correction of the radiation pattern. A lense can fill this two requirements.
Have fun....
73s
Andreas
Hallo,
I milled a little brass ring which is soldered to the copper tube. The ring fixes the lense.
Brass can be found in the plumbers junk box.
From my point of view, the diagrams from DD9FJ above show an effect I could see also. The increasing of the gain is less then the reduction of the background noise. The diagram gets smaller when using the lense and there is less noise receiving beside the dish. As a result the SNR is higher.
This can be seen more clearly, receiving the NB with a wide spectrum display.
So, the lense works as expected.
73s
Andreas
Hallo Matthias,
ich habe einen viel kleineren, etwas ovalen 80cm Spiegel verwendet. Das dürfte alles so passen.
73
Andreas
Hallo,
there are two types of LNBs tested here. OCTAGON OTLSO which has two indepedend LOs and Rocket LNBs VENTON and Red Eagle. Both work with 7,5 Volts. The Rockets can be combined now even with a patch or a helix.
Reducing the diameter of the LNB-Waveguide and increasing the copper tube a bit it can be sticked together smoothly. I prefer SMA-Connectors to feed the S-Band-Antennas to avoid mechanical collision with the LNBs and the mounting clamp. That's why the backplane of the helix shows a corner connector. At the front of the tubes is a small ring of brass to fix the lense again.
With the lenses I always expected more gain. It was'nt seen clearly. Looking to a wide spectrum, the difference between transponder noise and background increases. Probably the background noise gathering beside the dish goes dowwn with a smaller radiation pattern?
This is a wide spectrum without the lense.
Here is the same spectrum using the rocket lense. The reduced background noise can be seen in the waterfall also.
Looking to the Datasheet of the TFF1017 the question appeared, woud it be possible to modify the loop filter. The result could be improved phase noise of the LOs.
Of cours it is a very theoretical question and the transponder noise can be seen clearly above the LNBs noise even with a "normal" dish and the lense. SMD components are fare away from easy changing and experiments. But, may be....
73s
Andreas
Hallo,
I don't see the need to feed LNBs with 12V when only one polarisation is used. It can be reduced until the drop voltage of the regulator is reached. This helps to avoid unnecessary dissipation.
73s
Andreas
Hallo,
buying one piece of a 2,4 GHz-circulator in Asia means approx. 70 $ shipping and 25 $ money transfer.
It seems to be not in the amateurs budget. One possible way could be sharing this when ordering more pieces....?
What a pity.
73s
Andreas
