Author Topic: ADSB Ground-Based Antenna  (Read 10477 times)

PaulSS

Re: ADSB Ground-Based Antenna
« Reply #15 on: June 01, 2019, 12:13:20 pm »
Well, today I have mostly been playing with bits of coax  :) I made the collinear antenna yesterday and managed to get it up on the roof and the cable run to where my Raspberry Pi etc will live. It's now just waiting for the new dongle and other bits to arrive.

I did also make a spider antenna with eight legs (as all spiders should have). To say that I used Australia's supply of solder would not be an exaggeration. I really am not very good at all but none of the bits of wire are going anywhere, that's for sure. More is more will be my soldering moto. One day I may post a photo of the antenna but I'm too embarrassed to right now  :-[

I used 8 sections to construct my collinear antenna. RG6 cable (75 Ohms) and made the lengths 116mm each.

When you see a Homer Simpson-esque explosion over Western Australia you will know I have got the other bits and pieces and plugged it in  ;D

I apologise for the crap standard of photographs but they've been shrunk and resolution reduced so they fit on this forum.
« Last Edit: June 01, 2019, 12:16:11 pm by PaulSS »

AlanG

Re: ADSB Ground-Based Antenna
« Reply #16 on: June 01, 2019, 06:42:26 pm »
Hi Paul

I didn't bother to solder my spider, I just bent the ground plane legs to the correct length and angle and pushed the short ends down between the outer sheath and the braid/foil, fastened a small cable tie round the top and then blathered it all in super glue.  Worked a treat in the loft.  i have now replaced it with a coax collinear mounted on the roof along with the pro made Flarm and PAW rebroadcast antennas as mine is an OGN-R station.

Alan

PaulSS

Re: ADSB Ground-Based Antenna
« Reply #17 on: June 10, 2019, 06:49:59 am »
Well, I am pleased to say my collinear antenna works. I haven't compared it yet to my spider (and then a spider that I'll build that is the same as Alan's) but my maximum range detection so far is 208.4nm, which I don't think is too bad.

I had a bit of an incident last night when the horribly strong winds we'd been having blew down the pole holding my little weather station thingy and the ADSB antenna. The weather station is no more but my antenna now has the pole all to itself and seems very happy, despite the 40-45kt winds blowing at the moment. Small wonder the only traffic I'm really seeing is going into Perth (about 80nm north of me). No GA out today from Bunbury  :-\

I've now become a thorn in the side of the FR24 forum but I now even k now how to SSH my Pi and have actually loaded some programs to look at my 1090 performance graphs and map. It's all quite exciting but maybe I just need to get out more  ;D

exfirepro

Re: ADSB Ground-Based Antenna
« Reply #18 on: June 10, 2019, 08:41:22 am »
Hi Paul,

Some on that other Forum (you know who) might say you get out too much !  ;)   ;D

Best Regards

Peter

PaulSS

Re: ADSB Ground-Based Antenna
« Reply #19 on: June 10, 2019, 01:40:59 pm »
I replied the other day when someone called into question unmet PAW promises, while he flies with a unit where most of the 'snake oil' that was promised never came to fruition. Then I thought, 'why am I bothering' and deleted the reply. Luckily nobody was awake in the UK to see what I'd said.....I think maybe a bit too truthful and close to the edge  ;D

Anyway, 220nm is my new antenna record  ;D

Paul_Sengupta

Re: ADSB Ground-Based Antenna
« Reply #20 on: June 10, 2019, 02:44:36 pm »
Well, I am pleased to say my collinear antenna works. I haven't compared it yet to my spider (and then a spider that I'll build that is the same as Alan's) but my maximum range detection so far is 208.4nm, which I don't think is too bad.

Woohoo (noted 220nm "record" above). Told you a colinear was better than a quarter/half wave...  ;D

It's all quite exciting but maybe I just need to get out more  ;D

Welcome to the geek side! You'll be happy here. ;D

PaulSS

Re: ADSB Ground-Based Antenna
« Reply #21 on: June 12, 2019, 02:52:52 am »
Quote
Welcome to the geek side! You'll be happy here. ;D

It is quite a lot of fun. A few days ago I didn't have a clue what Dump1090 was and now I have a fancy map, with rssi numbers telling me 'stuff' AND a fancy, in-built, gain changing button AND all sorts of graphs ;D

I think the antenna is happier for being re-erected as I've broken my previous record  8)


Keithvinning

Re: ADSB Ground-Based Antenna
« Reply #22 on: June 12, 2019, 02:42:21 pm »
Nice One Paul
Perhaps you will put one up in the IOW when you return.
I'll reserve you some bits

Keith

PaulSS

Re: ADSB Ground-Based Antenna
« Reply #23 on: June 13, 2019, 01:43:44 am »
Yes, that is certainly my plan, Keith  ;D

It has been quite a steep learning curve for some of the Pi things. I literally had never even seen one until I set this thing up and I had no idea what an SSH or an FTP was. I don't claim to understand the code being written to my Pi but I'm getting pretty good at copying and pasting the codes suggested on the RF24 Forum and at least I can now talk to my Pi though my MacBook's Terminal (something else I didn't know existed).

I think program writing has moved on a bit since I used punched cards and BASIC for my O level computer studies (admittedly we did get super advanced for A level and used a fancy BBC B computer with a tape recorder to save our programs) but I think I might see if there is a book or YouTube course to see if I can get to grips with some of this Pi code and write my own program for spelling rude words. I assume that's what kids are still doing.

Yes, an OGN-R station will be fun  ;)

PaulSS

Re: ADSB Ground-Based Antenna
« Reply #24 on: June 22, 2019, 01:09:44 am »
Sorry, but had to do a bit of Geek trumpet blowing. Managed to crack the 250nm line  ;D