There is a new ExtIO.dll available for supporting HDSDR with RTL2832U based SDR sticks. This makes setting up HDSDR with these sticks a lot simpler and it also appears to perform much better. The installation only requires installing the Zadig drivers for you stick and placing one file into the HDSDR directory. I was having difficulty with HDSDR and audio dropouts with the older installation method, but using the new ExtIO.dll corrected the problem. If you have been having difficulty with HDSDR working properly, I would suggest you try this ExtIO.dll file. Here are the instructions:
- Download and install the Zadig drivers if this is the first time you have have used your RTL2832U stick. You will need 7zip to extract the files. When finished extracting you will see an Zadig.exe file. Plug in your RTL2832U stick. Be sure to do a list all devices in the optiond menu to see your stick. This will usually be a bulk-in, interface (interface 0) device, or it could just say RTL2832. Once selected proceed to install the driver. Note:If you are switching to a newer R820T based stick, it would be a good idea to upgrade your Zadig drivers anyway.
- Download and install HDSDR.
- Download the new ExtIO.dll for RTL2832U devices. Unzip, look in the folder labeled Release and copy the file ExtIO_RTL.dll to the directory where you installed HDSDR.
- Start HDSDR. If ExtIO_RTL.dll is the only ExtIO.dll file, HDSDR will start immediately. If you have an additional ExtIO file in the directory from a previous install, you will get a file manager page first. You should then select the ExtIO_RTL.dll and you are good to go.
One little strangeness, is that if you start HDSDR tuned to a frequency that you RTL2832U does not support, you will get a “Pll Not Locked” popup message. Just ignore it and tune HDSDR to a supported frequency and the message will go away.The author has since corrected this problem.
- Once HDSDR is going click on the ExtIO button next to the frequency display. This will bring up the ExtIO control panel. Here you set the gain of you RTL2832U stick for best performance. This very important, because if it’s too low, you won’t receive much. However, if it’s too high, you will get more noise, RFI, Front end overload, and reduced sensitivity. It’s best to experiment with these settings a bit to see what works best with your stick and antenna.
Thats pretty much it. Simpler and better performance in my opinion.
Note – For those who are getting the ExtIO.dll not active message, this because you do not have the Zadig driver properly installed for your RTL2832U. If you move the RTL2832U from a previously installed usb port to a different usb port, you will have to reinstall the Zadig driver for that port.