Today I got all excited and thought about seeing what kind of range of usable range i could muster by connecting a small amp to the DMR hotspot and connecting it to the outdoors antenna. I was putting about 0.5w out into a slim jim about 3m off the ground. I could still hear the kerchunkers about 1km away. Nothing stellar but you really could not expect to much giving the setup.
So after that I got all excited and connected the Hackrf to the same little amp and again to the outdoor antenna and fired it up in FM CW beacon mode and got an ultimate range of about 3Km. Again nothing stellar but considering everything, not to bad either.
So the moral of the story here is I really need to get the antenna much higher into the air if I want to be able to turn this into something a little more usable without resorting to much higher power.
Chives, coriander and rocket.
Sage and basil.
Spinach and roma tomato.
3 types of chillies and garlic.
So a number of what we all call SDR receivers are capable of transmitting. The output power in the case of the HackRF one is about 250mV p-p, in other words a very small signal, 0.15mW. This is not much good for transmitting further than the end of the street, but with some amplification you can get that up some. I added the QRPLabs 10w TX to it and was getting close to 0.8W and was being heard over 800km away.
Anyway, my plan for a while has been to use the HackRF as a receiver and make a couple of low power CW transmitters to go with it. By low power i am talking in the 10w kind of range. But this has gotten me thinking, with some VHF and UHF amplification, this might be a really cheap and easy way into SSB and CW on those bands for field day here in VK. It would require a 2nd SDR to act as the receiver, because the HackRF is only half duplex and there is no software out there that can so the switching currently, and it can be locked to a reference signal so it might be somewhat useful.