Hey all! I'm fairly new when it comes to being able to feed data consistently. I started dabbling way back years ago, but only recently have I had time to settle down and start enjoying some of my hobbies. I used to feed my own weather station to Wunderground and a tiny bit to FA. (Don't worry, not FA anymore) Last Thursday I ordered the dual ADSBx feeder kit and I think I ended up getting the last one in stock at the time (It's already back in stock, that was fast ). I also ordered a new 1090/980 antenna from ADSBx and it came yesterday. I ended up buying a RTL-SDR V3 and a HackRF fairly recently, so I started trial and erroring some things, and even made a VERY TEMPORARY antenna setup with some stuff I had around just to see how it worked out before my permanent feed kit arrives this coming Monday. I know PVC pipe wears quickly and I will be settling for permanent setup soon. Here's what I did in a couple minutes just to mess around and test things out a bit (I'm facing East while taking this pic): My range has extended a bit compared to my old FA antenna, but I'm using an old 300FT coax so I'm sure the amount of data loss is astronomical. Would anyone happen to know when/if the 50ft LMR240 line will be back in stock? I'd really prefer to use that when it becomes available. You can see below my range is about 260.6km (161 miles). Not great, but not terrible. Max range I saw today was about 332km (206 miles), but I think that was merely a stroke of luck. The issue I've had the past several years is that the neighbors behind me have allowed their once beautiful field to grow full of pine trees, so I'm not really able to feed much in a Westernly direction unfortunately. Even extending the height of the antenna only helps so much, and I'm not looking to put up a cell tower like everyone here thinks I'm trying to do If anyone has any suggestions for me for a permanent setup in the near future, feel free to give me some advice. I'm thinking at most a 25-30ft mast off the ground in terms of height that I'll be manning down, and I will most likely be putting some other antennas on it, mainly for HAM etc, but that may change depending upon how I feel and/or advice I may receive. Thanks!
If you do broadcast from the same mast you'll need to add extra filtering before it goes into an LNA (that's the thing the amplified SDRs have as first link). Have a look at the FA barrel filter. There are other vendors for coax, check these links: https://github.com/wiedehopf/adsb-wiki/wiki/adsb-receiver-shopping-list#coax-cable
Ah that's excellent, thank you! Just to clarify, I believe I read somewhere that a filter should be near the antenna and not the receiver/SDR/Pi, is that correct? If so, I'd like to get a few things to weatherproof it. I appreciate your help and resourceful link.
That's the rule for an LNA. With a filter the location before or after the coax doesn't matter. But if the attenuation of the coax run is less than say 3 dB it's quite acceptable for ADS-B to not have a mast mounted LNA. So if the coax is low attenuation and the run isn't super long it's not an issue. Systems with a mast mounted LNA get quite a bit more complicated as you also need a biast either internal to the SDR or as an extra component.
Thanks for your help, the support and information you've given me is top notch. As I side note, I recognized your username in a few places (cemaxecuter comments on YouTube) I know the RTL-SDR V3 has Bias T, but obviously I will be using what's provided in the package coming tomorrow instead. So as I mentioned previously, I ordered the Dual Feeder kit from ADSBx, and in the description it mentions including an additional external filter. https://store.adsbexchange.com/products/deluxe-dual-sdr-feeder-kit So I'd assume I can just use that (Only for 1090Mhz) instead of having to purchase the barrel filter from FA, correct? So if I plan to run 978 as well, then I'd need to obviously get an additional one.
Well just see how it works. You're not gonna be transmitting permanently i'd presume? Hobby power levels aren't gonna damage anything, the receiver will just not receive while you're transmitting which isn't a huge deal. You just need to place the ADS-B antenna above or below the transmitting antenna with as much distance as possible. Above is likely better and if the transmitting antenna is vertically polarized as well, placing them underneath each other will provide the least amount of coupling. What kind of coax and what length are you planning to run? I haven't tested it personally, but the 1090 filter is a bit more attenuation due it being a SAW filter, so having it in front of the LNA can be suboptimal depending on the coax attenuation and the attenuation due to splitting the signal. Once you have everything set up, i'd recommend testing with and without the 1090 filter, probably a week each.
Nah, I won't be transmitting much. I'm still debating on HAM equipment and currently only have an Icom ID-52A, so that'll be sometime in the not-so-short future. As far as cable in terms of ADSB goes, I still haven't ordered get but I'll do that sometime today. Right now the 300ft cable is just too much and completely unnecessary. I'll probably be buying a 50FT Coax. And when I get my HAM stuff going I'll probably do the same length for that as well. I'll do a week with and without the filter and compare the results. Thanks!
Just check the attenuation and get something with less than 3 dB or so over the whole run (for 1090 MHz). Lower attenuation is usally thicker coax and harder to bend / handle. But it depends on the brand / product.
