Yesterday I finally go round to building the MiniTiouner V2. I order the parts to build this a few weeks ago with the plan to experiment with the receiving of QO-100 (aka Es’Hail 2).
Background / Reasons for Building
By using the MiniTiouner this would allow me to:
- A) receive and decode the low symbol rates DATV transmissions.
- B) use the old sky dish and LNB that is currently sat unused on the side of the house.
The reason for need the MiniTiouner for using the of Sky Dish / Universal LNB is that the Local Oscillator (LO) in the Universal LNB’s is 9.75GHz. This is perfect for the standard FreeSat / Sky signals as it puts the Intermediate Frequency (The frequency that comes out the end of the coax) within the tuning range of you satellite receiver.
The problem with using the universal LNB on the amateur frequencies is that they are slightly below that of FreeSat and sky signals. This means that ,after mixing with the LO, the Intermediate frequency coming out the coax is too low for most satellite receivers (Around 750MHz rather then 900MHZ – 1.2GHz).
You can modify the LO in LNB’s to around 9 GHz. This brings the Intermediate frequency of amateur signals up into the tuning range of standard Satellite receivers.
I currently use / bought a pre-modified LNB off ebay specific for use with ATV. It’s current use is for receiving my local 10GHz ATV repeater GB3LX.
The Build
On the BATC Wiki pages there is a detailed description of the MiniTiouner Board. It also provided the schematics and a List of the components required.
Components / Tools
The MiniTuiouner has been designed by a number of people but the BATC have put together there own version by providing pre-made Blank PCB boards, The tuner module, a hard to come by voltage regulator and a pre-programmed USB Converter board.
These are available on the BATC website, although you need to be a BATC member to purchase them. Digital membership is not that expensive.
- Blank PCB
- Voltage Regulator
- Tuner Module
- USB Converter Board
The remainder of the components can all be bought from DigiKey and are usually delivered within a day or two of ordering.
You will also need to aquire a DC-DC converter. These are easily available on ebay if you search for “MP1584 step down buck regulator”. Here is a link to one I got.
The only Tools I used was a ‘helping hand.’ This allowed me to push the components through the holes in the PCB and solder them in place before trimming the legs.
A Soldering Iron. A low power one should be all thats required apart from some of the large tabs (The fuse holder and Tuner Can Tabs) which may require a bit more heat to get it soldered quickly enough.
Finally a pair of wire cutters to trim all the legs off the components when you have them soldered in place.
A Soldering Iron. A low power one should be all thats required apart from some of the large tabs (The fuse holder and Tuner Can Tabs) which may require a bit more heat to get it soldered quickly enough.
Finally a pair of wire cutters to trim all the legs off the components when you have them soldered in place.
Construction Time
WARNING: If you have got the box that is recommended on the BATC Wiki then you will find that the PCB is slightly too big to fit into the box. To solve this I used a small needle file and filed down both sides of the PCB till it was a snug fit.
Firstly I went through all the components I had and found all the smallest ones. I saved the small ferrite chokes till later on as they would be easily damaged.
The Reason for putting the smaller components in First is because if you put taller components in first it makes access with the soldering iron for the smaller ones more difficult.
First components to go in were the Resistors.
I then put in the small capacitors, diodes and the small headers.
The next parts I put in was the components for the DC Input and Input protection.
After installing these components I found that it would be easier to Install the DC Jack before the Fuse Holder. This is because with the fuse holder in place it made it difficult to solder the centre pi of the DC jack.
As you can see above I also fitted the 3 voltage regulators. Finding the right bend point took a bit of fiddling to get them to look neat and also have the fixing holes aligned.
Next up was the socket for the USB converter board. This was a little tricky as you need to hold the socket in place till you have at least one pin soldered. Once you have one soldered then you can turn the board fully upside down and do the rest.
I soldered the pins in an alternating pattern, top right, bottom left, top left, bottom right. This was to try and spread the heating effect so each part of the header had time to cool before it was heated for the next pin.
The socket shown in the bottom left is not part of the kit / List of parts. normally this chip would be soldered directly onto the board but I had some spare sockets from a previous project and thought I would use one to make future issue easier to fix.
Finally I installed the Ferrite Chokes, and then the large capacitors.
You will see above that I have also fitted the DC-DC converter.
To do this I first Tinned the pads and holes on the PCB. I then took some of the thicker Leg offcuts from the fitted components and while heating the solder, pushed them through the holes of the board.
After doing this with all 8 holes and ensuring that they were all correctly soldered in place both on the top and the bottom. I slid the regulator board down over the pins till it was a few mm above the main PCB. I then soldered all the pins to the regulator board and trimmed them all down.
You will see just to the left of the DC-DC Converter is 2 small wires. This is a slight modification i did. Instead of fitting the small 3mm LED to the board I used some wires so I could fit the LED into the front of the casing so I know when the power is on to the board.
Finally, in order for the MiniTiouner to work with the V0.8 software a small modification needs to be made to the USB Board for you PC to detect the tuner correctly.
A resistor between 5.6k and 12k needs to be fitted between CN2 Pin 19 on the USB module and ground. I didn’t have a resistor to hand of the right value so put a 5.1k and a 1k in series. It looks a bit rough but it works.
Testing before installing the Tuner Module
It is highly recommended to set up the voltage rails before installing the tuner module. This is to prevent accidental damage.
BEFORE APPLYING POWER FOR THE FIRST TIME ENSURE THERE IS NO! JUMPER ON J2!
This will allow you to set the voltage of the DC-DC Converter before supplying voltage to the regulators for the rails as they only take a MAXIMUM of 6v input.
Using a multimeter, set the output voltage of the BUCK regulator to between 3.7 and 4 volts. To do this, preferably using a plastic screwdriver, turn the small variable resistor. This is very sensitive and only requires very small movements to adjust the output voltage.
Once you have the voltage set, Fit a jumper onto J2 and then check the voltages on the tops of the 3 Ferrite Chokes. you should have 2 at 3.3v and 1 at 1.2v.
I then installed the Tuner Module, fitted the USB board and the chip into the socket.
Testing
Ensure there is NO jumper on J3 & J4. These jumpers apply power to the Ftype connectors of the tuner. So unless you need to pass your main DC input to power an LNB, ensure these are open to prevent damage to the tuner module.
Into the testing phase.
You will need to register on the VIVADATV website in order to download the MiniTiouner software.
Firstly I connected my antenna that is currently used to transmit into GB3VL. I then applied power to the board, 13.8v, from a standard bench power supply. Finally I connected the USB to my computer.
Before first starting the software, from the folder, run ‘LAVFilters-0.71-installer.exe’ as administrator. This will install the required video filters onto you PC to enable the MiniTiouner software to display the decoded video.
You will also need to run, also as administrator, ‘install_usrc_ax_winXP_Win10.exe’ to register the filter files.
Now you should run “CheckMiniTiouneDriverAndFilters_V0_5a.exe”.
Click USB tuner
If all is good then some text will appear in the window and all the lights below the button will go green. This means the tuner is ready to go.
You can also click Directshow.
This will check the LAV filters etc… that you have just installed plus a few other things. Again if all is good then all the lights below the button should go green.
Finally you can start up the main software by running ‘MiniTioune_V0_8s.exe’
I will do a more detailed guide on running the software once I am more familiar with it but for starters the main controls are on the left of the window.
Here you can set the Symbol rate ‘SR’ where 04000 would be 4Msymbols
The frequency where 01310000 would be 1310MHz or 1.31GHz
The offset. This is were you would put in the LO of your LNB or Converter. EG. a Standard Universal LNB has a LO of 9750MHz which would be ‘09750000’ in the software. Set this to all 0’s if you have no conversion.
Below this are settings for the FEC and mode, DVB-S or DVB-S2.
If you set these correctly, and the signal is strong enough, you should now see a picture.
Above is me receiving GB3VL on 1310MHz 4MSymbols 1/2FEC DVB-S.
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