Wednesday, March 1, 2017

HackRF One - Getting Started

I finally broke down and bought a HackRF One from Great Scott Gadgets. I could have bought a clone for a lot less money, but I wanted one straight from the source, if nothing else, to increase the likelihood I will get the performance specified.

Unboxing was uneventful. I got the version with the ANT500 antenna. The foam inserts were more than enough to prevent damage during shipping. Caps on the SMA connectors ensured they arrive safely. Overall, a great looking box and well thought out to ensure they arrive safely.

Getting it up and running, that's a whole different story. I downloaded every software package listed as compatible, after using Zadig to install the drivers. I continually got an error stating "Cannot open HackRF device. Is the device locked somewhere?". It turns out, after some digging, that apparently the USB port you attach it to can determine whether or not it works. I swapped the HackRF with my Logitech Unifying Receiver in the front USB ports and voila! The HackRF One came to life. From what I've read, it's not uncommon for only a single USB port on a PC to work properly. I've NEVER had a USB device that finicky before,

I performed my standard "test" for any VHF capable receiver, tuning to the local NOAA weather channel. I live relatively close to the 300W transmitter, and I can generally pick up the station without even having an antenna attached to a receiver. Unfortunately the HackRF One wasn't "this good". I had to fully extend one of telescopic sections before receiving a decodable signal. Fully extending the whip greatly increased the signal strength.

Those tests were all performed with the LNA gain at 0db, the VGA gain at 18db, and the Amp on. Reducing the VGA gain below 12db made the signal illegible.

One part that I was happy about was the CPU utilization. My PC was at 7-8% before opening SDR#. At 20msps that jumped to 15-16%. 8% CPU utilization for 20MHz of bandwidth is acceptable. Keep in mind, this is not a slouch of a PC, I have an Intel Core i7-6700 with 32GB of DDR4 RAM.

One quirk is that in 20msps mode, tuning too fast, or too far, caused SDR# to crash. Reducing the bandwidth to 10msps eliminated this issue.

FM Broadcast band reception was much better, but this is to be expected considering we're talking KW transmitters vs the 300W from NOAA. Some local AM broadcast is outside of the specs of the receiver, and was a complete no-go, while some AM broadcast towards the top of the band came in beautifully. The ham low bands which showed quite active on my Apache ANAN were dead to the HackRF One, but again, we're talking about a tiny whip antenna, so we can't expect miracles here (no pun intended towards the Miracle Whip antenna).

At the end of the day, I think when I get around to connecting proper antennas I expect to see performance improve greatly, and I see huge potential in this little box. A worthwhile purchase, and a keeper for sure.