KiwiSDR Location and Off-Grid questions
I'm thinking I want to get and install a KiwiSDR2 when available.....I'd love to be able to decode WSPR across all bands on one channel, remote listen on another channel myself, and leave 1 or 2 channels open for public use/sharing.
I have 3 locations possible:
1: Main house in the city. RF noisy environment, close to others (8 ft between houses) and power lines. (above ground.) Not a lot of antenna options. But, cable internet here.
2: 2nd place, a cabin I'm building. Away from towns, but at the edge of a group of subdivided lots. I have 4 acres to work with....has power, DSL (600mbps upload speed). But I have neighbors w/ outdoor LED lights, the DSL lines, overhead wires, cabin has lots of LED stuff, etc. I'm also 0.6 miles from high-voltage transmission lines. I COULD get the SDR/antenna 280-300 ft from the nearest houses and power line here. This area is all 70 ft+ pine trees. So some lightning/storm potential.
3: My family owns a property down the road from the cabin. I've got acres to work with there. It's 900 ft from the nearest buried power line, 1200 ft from any DSL line, about 1200 ft from overhead power lines, and 0.8 miles from the high voltage lines. BUT, no services. I would need to implement a 2200 ft+ wireless link back to the cabin (through trees/across a road) (with the 0.6 Mbps upload speed there) and an off-grid solar/battery setup. This area is more open, less trees, and bigger potential for lightning issues, I'd bet.
My questions:
How can I quantify the noise/noise floor of an area with an existing SDR? (I have an SDRPlay RPS1A) Seems it depends on antennas, RF gain settings, time of day, frequencies, etc. Do I survey each with a standard antenna and laptop on battery and somehow make some calcs?
How bad would option 2 location be with DSL noise nearby and power lines and neighbors 300 ft away? (guesses?) Certainly better than my main house in the city, but not sure about how much the noise floor would be above option 3... Like is a few db worth all that?
Anyone know the actual power requirements over time of a KiwiSDR? Wondeirng how big a battery and solar setup I would need to support a wireless link (2.4 ghz with parabolic antennas?) and the Kiwi SDR itself, and probably a rPi running to decode WSPR, too? I can't find any stats on what it uses statically..just that it may need 1.7-2.5A at 5V at startup? I have some expeirence with panels and batteries, and have an idea of what I could harvest in this location for solar.
Really, I'm trying to figure out if it'd REALLY be worth the hassle and cost to set up a Kiwi SDR remote site vs using location 2 where I don't need batteries, solar, wireless link, or an rPi (could run WSPR decoding on a laptop). Certainly I COULD start at location 2 and move it to 3 eventually...but getting an antenna up, and getting things run a couple hundred feet would still take some cost and effort.
Interested in your thoughts
-Nate
N8BTR
Comments
I think option 2 is the most practical to implement, and still have a decent level of performance.
You have enough space to distance yourself from the main noise sources, and option 3 involves adding potential new noise sources anyway.
DSL shouldn't be a problem, and if it is your own, you can do stuff to improve the line balance, which will solve most radiated noise issues.
Taking a broadband loop antenna and SDR Play-1A with a decent panoramic waterfall / spectrum display (or the useful spectrum analyser app that is available https://www.sdrplay.com/spectrum-analyser/ ) to the various sites should provide you with some confidence in your decision making.
Good luck,
Martin
I had a lot of trouble with my neighbors VDSL lines though.
In the past weeks I've been walking around in my area with a Malahit portable SDR to locate noise sources.
And I concluded that you can be lucky and have low noise in a populated area, or you can have bad luck and just one neighbor which could cause a lot of noise. But the further away from other buildings, the better are your chances.
If you have favorite bands which you would like to receive, it would be perhaps easier to monitor them first. But observing the entire spectrum can require a lot of time and effort.
Maybe you can set up the kiwi first where it is the most convenient for you, and move it to a quieter location, if that turns out to be too noisy?
Thanks for the input!
While I do have DSL in the area, I'm far enough from the DSLAM that the copper pairs buried near me are too far to use VSDL... so at least the local DSL interference I think would be more limited to 2.2 mhz, and not all the way to 12mhz. (I'm like the 2nd or 3rd last house on the line, the copper line run literally ends a few hundred feet from my cabin property.)
I had no idea that there was a spectrum analyzer app for the SDRPlay stuff...Brilliant! I'll have to make some sort of portable/repeatable antenna setup for testing this at different locations.
Location 2, my cabin.... poking around more, I'm seeing people are using KiwiSDRs on Wifi powered by the BB USB port....that may be ideal for this scenario, as I could then get away with running a single pair of wires for DC power to a weatherproof box the SDR would be in at the base of the antenna feedline.
-Nate
N8BTR