Agreed on the front end of the hackRF - this one has already been repaired by me as a friend gave it to me and said, it's deaf - if you can get it going again, it's yours as I have got a new one!
They are renowned for frying the pre-amp chip if it is activated and then a strong nearby signal is fired up close to it and that's what I had to replace (the pre-amp chip) to get it running again.
Apparently, Hams are often keying a handheld too close to it :-(
I used it with a short 1ft (30cm) whip and low gain settings in the spec-an software/hackRF, that's the best way to run it, low gains and increase as needed.
Without any antenna connected, I only saw the main signal at low levels.
The free spec-an s/ware for the hackRF is here, in Linux and Windows flavours (scroll down to the 'Downloads' section)...
I didn't need to run Zadig in my Windows 7 64bit machine as the hackRF installed in Windows automatically.
If you have a cheap RTL-SDR dongle and hack it for HF/use a converter, you can find spectrum analyser software for them as well.