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This is how you will setup a Automated NOAA Weather satellite imaging system.
This system is available from Giga Technology
Here is the link to a live system in South Africa
Here is a sample image
This board is now complete and is available from Giga Technology.
This repository will have all the files for the PCB that fits on a Raspberry Pi witch will have a 7 stage low pass filter for the VHF 2m band. (About 60db down for first harmonic)

This board is to be used with the rpitx utility to alow you to transmit on the 2m VHF band. This board will have 7 stage lowpass filter. Here is the filter design details. Alt text Filter similator Diagram Alt text The PCB files is Kicad file format. The circuit diagram

Alt text PCB layout diagram during design Alt text

Changed Connectors transistor and regulator Alt text

3D view of Board

This Board is now avalible from Giga Technology
The Zastone D900 is the latest in affordable 70cm DMR transceivers - It's a variant of the TYT MD-380 (aka: Retevis RT3) and gives you access to the new DMR mode as well as conventional analogue FM repeaters.  The radio uses the same firmware/internals as the MD-380/RT3 but has a slightly different case style.  One of the benefits of DMR is the use of TalkGroups and Time-Slots which allow 2 conversations to take place on a single frequency. This means that a repeater can be used for a local (RF) QSO at the same time as supporting a world-wide QSO.
First download the windows programming application from the shared drive
Download the D900.rar
unzip the rar file
Then execute the CPS-DR780 Setup V1.26.exe  application and install the programming application.
Then download the D900 config file from the shared drive.
Here is a link to the DMR Network configuration data so that you can check that you have the correct details.

It is very easy to monitor your grid tie Inverter power contribution to the grid by using the POW Onoff.
This Pow Onoff motoring device and inverters is available from Giga Technology. here is the link
Just connect your grid tie inverter to the load side of the Pow Onoff switch and the power side to the utility power outlet.
Connect the power to the internet using the Mobile application and that it. You now have full view of your contribution.
Using the Onoff Pow power switch you can monitor your power consumption and control your usage from the internet on your mobile phone.
This Pow Onoff device is avalible from Giga Technology here is the link

Here is a connection diagram.


Remote turn on/off using APP EweLink
Check power consumption over any time interval such as daily, monthly
Check energy consumption in real time (instantly)
Supports configuring fast SSID changing and password connection through eWeLink
Supports auto-connection to server, register and updating device status
Supports tracking device status on eWeLink
Supports single, countdown and repetitive tasks

Here is some screen shots of the mobile application linked to your Pow Onoff device.
I was so simple to enable the the app by purely connecting to your local network and then starting your POW device keeping the button pressed for 5 seconds on start up.
The mobile app picked up the Pow device and made it available over the internet.

The new KiwiSDR is live and running ant the first production boards is available for purchace.
Here is the link to the Live SDR in South Africa
Steps to follow
Link to Screenshots of chines menus and here

1. Download the latest firmware for the TL-MR3020 model from TP-Link:
2. Unzip the file
3. Follow the instructions from this website but, instead of flashing OpenWRT, flash the .bin file obtained from the step above.
4. Configure your router and you are done. The configuration interface address is Username and password are both "admin".

If something goes wrong and you brick your router, the instructions below can help you:

More info here
Spectrum Analyzers / The NWT70 Spectrum Analyzer 0.05-85 MHZ
« Last post by Anton Janovsky (ZR6AIC) on September 30, 2016, 05:37:45 PM »
The NWT70 Spectrum Analyzer 0.05-85 MHZ
This Spectrum Analizer is avalible from

This is a proper spectrum analyzer that could tune antennas as the Signal generator track the receiver.

Software that can be used.
"SMA Spectrum Analyzer 138MHz-4.4GHz".
Basically it uses only one ADF5430 chip instead of two and hence cannot be used for antenna tuning (which was the original NWT series purpose), as the signal being output cannot be read back in at the same time (a second ADF5430 chip would be needed).

Although if you use the Noise source that is soled with the device it can still be used to tune antennas and filters.
1) Noise source  >>>>> filter >>>>>>> spectrum analyzer.
2) Monitoring Frequency spectrum signal.
3) Monitoring Harmonics first and second.
4) Deviation and Modulation checking.
5) Signal generator can be used on its own.

The included software (WinNWT) is a freeware made by the original author of the NWT series of devices (NWT500), which is not particularly nice for pure spectrum analysis.

Here is some links to other versions of software.

The software is free
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