Ebay - Outdoor Antenna?

Morning all,

Currently running an attic-mounted “spider” antenna - works well, but the next step is to get this on the roof outside.

Recent gales here have speeded my decision (I have a slate off)…

I know a few of us on here make and sell their own external antennas on ebay - could someone recommend one for about £20?

Have seen the same “spider” antennas, but housed in (pvc?) tubing?

I bought one on eBay from a guy in Slovakia called stanislavpalo130. It has worked well for me and cost less than £20 including delivery, Note: it has now gone up to just over £20.

ebay.co.uk/sch/stanislavpalo … 7675.l2562

I’ve been running one of these for about a year ebay.co.uk/itm/191595766728 - with a satalite amp fixed an adaptor at the bottom of the antenna.

I believe it’s a printed circuit collinear - but I have no proof

I bought the same antenna with the same guy… I’ll put on the roof. I hope it works perfectly.

Do you have a graph that shows working of this antenna? … coverage, etc.

Thanks!

The price for that one over here is $71.50 US with free shipping from Bulgaria (shocking) - although it may very well take it a month to get here.

I’m using a home-brew eight-element collinear in a PVC pipe on the roof that has served me very well. If I were to order one of those, I would just have to open it up to see what I paid for. PVC is easy enough to re-seal. :slight_smile:

Has anyone ever opened one of these Internet-purchase ADS-B antennas to see what they paid for?

Matt

I have one without the ground plane and the guy is actually quite helpful, his English is a bit off but nevertheless he’s handy and I wouldn’t recommend taking it apart i broke one doing that haha. I did send him a request for it and he found a work-around for what I wanted.

@Mattbna the one above without a ground-plane is a J-Pole antenna which does have quite a good coverage when in clear sight of the sky. I’ve got atleast 150nm-200nm easy although my area doesn’t help. Can’t comment on the 5/8 antenna with ground plane but I am tempted to get one.

I had the antenna open after a storm. :imp:

looks something like this, but the copper is coated with anything in silver color I do not know what it is.

http://home.arcor.de/papasven/bdant.jpg

The image you linked is providing a 404 error. :slight_smile:

Matt

It’s just you. I’m seeing it just fine.

We’re both seeing it now…over two hours later. :slight_smile:

I copied the original photo link to another tab in two different browsers earlier and it 404’ed in both. Was originally dead.

Matt

Thanks for the feedback!

Yes, that’s just the sort of thing Im looking for - will order shortly…

Whats the latest on lightning-arrest ; grounding the antenna in case of lightnig strike?

Have seen a couple of “connectors” that go inline on the Coax, with a connector presumably for a ground wire…

How do these work, where do I get them etc?

Ta

Hmm… just read elsewhere that most people tend not to bother…

To quote another site “Do you have a TV Aerial - has it ever been a problem (with lightening)?”.

No.

So - unless anyone has any wild feelings to the contrary, dont think I’ll bother.

I would definitely provide some earthing/grounding of the antenna - f only to deal with static build up. Without it your raspberry Pi Ethernet port will had a tendency to sacrifice itself to protect everything else.

(not uncommon!)

If you are using a DC injector that should prevent any static build up from reaching the receiver.

Yes - especially as the antenna is higher than the roof ridge, I’d prefer to err on the side of caution also…

So, what’s the best way to do this - what do you external antenna guys do?

Out of interest, the link I found suggesting “not to bother” …

"
I always ask have you ever had a problem with a TV antenna or FM stereo antenna?
If the answer is no then why would your adsb receiver be any more exposed?
"

… is here:

radarspotting.com/forum/index.php?topic=2543.0

That thread also warns about not grounding the antenna for fear of making it into a “lightening conductor”.

… All for academic interest only, ultimately I’ll go with advice from yourselves.

FYI, I got a radomed-Ground Plane from one of the links earlier in this thread.

Good point Caius, I am using a DC injector!

Rather than killing the Pi (which admittedly isnt ideal), Im ultimately more concerned about burning down the house!

So, as I have the DC Injector, where do we stand on the lightening arrestor / static protection?

Those who like to declare that safety items are useless, are fools. Or grounding increases the chance of a strike…no. At the energy levels of lightning (the lightning’s prospective), everything is grounded. It just an issue of how you would like to direct that energy (to prevent a fire). Would you like your walls and framing to conduct the strike to ground, or would you perfer a 4 ga solid copper wire to direct it. I personally don’t like my walls to be electrified (due to the inherent fire afterwards). The NEC is there to keep you safe.

Linked is a good article.

http://www.reeve.com/Documents/Articles%20Papers/AntennaSystemGroundingRequirements_Reeve.pdf

well, it would block static from going down the core of the antenna coax, and to some extent the antenna might be grounded through what ever it’s mounted on - but with a home made antenna that’s insulated from it’s support, running off an insulated power source - the best ground could easily be the Ethernet port.

It’s no big deal grounding the coax shield.

Thanks for all the input gents,

So, looks like we’re recommending something to arrest / divert a full on strike…

What cost are we looking at here, any links to products etc?

Re Grounding - my Pi, amp and network point are all mounted on to a roof joist in the attic.

THX

Found this in another thread (knw i’d seen it somewhere…)
ebay.co.uk/itm/Lightning-Pro … 5affa91f9a

I believe I’d need enough copper wire to reach the ground, + 1.5m ground spike?

However, would something like this do any good?
ebay.co.uk/itm/Brennenstuhl- … 5af0099afd

Thinking - ground it to the house ground via Amp / Power inserter / Pi plug?