ADS-B DIY Antenna

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jepolch

Active Member
I was going through a review of RPi B+, and found this:
"One major problem we had during the setup process was that the microSD card slot lasted for three insertions and removals before a spring inside gave up the ghost and the card would no longer stay put. From then on we had to use sticky tape to hold the microSD card in place, which was effective if unsatisfactory. We found ourselves missing the full-size SD card slot of the previous Pi."

Has any one faced this problem of microSD card holder break down?

http://www.expertreviews.co.uk/pcs/1400624/raspberry-pi-model-b-review
I've been using my first B+ for about two months. I've taken the micro SD card out at least a dozen times. I haven't had any problem with it. It feels solid when I insert the card. No indication of anything going wrong. I'm pretty easy on my stuff. It's a fragile thing, that connector. I can see someone with a heavy hand putting too much pressure on it and breaking it.
 

garylovesbeer

New Member
If you cut the can height to 69mm, there will be some improvement in performance. I dont recommend cutting your current beans can as it has a nice rounded edge, but because aluminum is easier to cut & make hole, recommend you make another one with aluminum drink can (pepsi, coke, beer etc) of 66mm or larger dia.

Generally 355mL (12 oz) & 710mL (24 oz) cans both have 66mm dia, the length of 710 mL can being double the length of 355mL can. The 66mm-70mm dia seems to be optimum. Larger than 66mm dia is ok, but does not improve performance. Reducing diameter below 66mm reduces the performance. The more you reduce the dia below 66mm, the more the performance reduces.

From memory the can has a cut length of 69mm and the antenna also is 69mm. The diameter is 70mm so all to spec.

I prefer the steel cans as it is more robust for handling purposes. I am handy with snips so have no problem cutting to any length and have drill press so no probs with the hole.

Might give the conetenna a go once the results are in.
 

garylovesbeer

New Member
I was going through a review of RPi B+, and found this:
"One major problem we had during the setup process was that the microSD card slot lasted for three insertions and removals before a spring inside gave up the ghost and the card would no longer stay put. From then on we had to use sticky tape to hold the microSD card in place, which was effective if unsatisfactory. We found ourselves missing the full-size SD card slot of the previous Pi."

Has any one faced this problem of microSD card holder break down?

http://www.expertreviews.co.uk/pcs/1400624/raspberry-pi-model-b-review

Haven't had this issue but did wreck a model B SD slot by dropping the RPi. Not happy Jan.
 

jepolch

Active Member
New conetenna in the works. Now with corporate sponsorship. :D
 

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jepolch

Active Member
I made this conetenna a little bit differently. Before cutting out the template shape I stuck strips of clear packing tape on the uncolored side of the metal. This gave the metal a "plastic" feel and it seemed more easy to work with and maybe less susceptible to dents and dings. Instead of gluing the edges together with super glue like I did last time, I put a strip of double sided craft tape (actually there's no tape, it's just a strip of adhesive that comes off a roll) on the inside of the non-tabbed edge and then joined the ends. Once it was cone shaped, I poked holes through three spots with a very thin awl (looks kind of like an ice pick), then followed by drilling the holes the correct size for the rivets (2.4mm). <-- metric :p
 

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Sjacket99

Member
Nice. Looks good. I been pretty busy today. Working on building 2 walls around my 19 inch rack. I have it in the corner. So we built 2 walls to close it in. Just finished up for today.
 

jepolch

Active Member
Nice. Looks good. I been pretty busy today. Working on building 2 walls around my 19 inch rack. I have it in the corner. So we built 2 walls to close it in. Just finished up for today.
Thanks! The contenna is easy to make and requires no soldering, so the outcome looks nice and neat.

I hope you're planning to put in some good ventilation after you close in your rack. When I worked in IT at a university back in the day, we used a 3 ton A/C unit to cool three racks. It was overkill, but without A/C the gear would have melted. ;)
 

Sjacket99

Member
Thanks! The contenna is easy to make and requires no soldering, so the outcome looks nice and neat.

I hope you're planning to put in some good ventilation after you close in your rack. When I worked in IT at a university back in the day, we used a 3 ton A/C unit to cool three racks. It was overkill, but without A/C the gear would have melted. ;)


I have my server rack in the corner of the garage, then we built the 2 walls. The garage stays pretty nice as in temp. All the walls have insulation in them and the ceiling. But I am putting in a 12x12 inch filter grill on the bottom of the door and near the top of the door I am putting in two(2) 120 mm fans that are 120 Volt. Each moves around up to 100 CFM's. Plus I am hooking up a cool only thermostat, so we the temp goes up the fans kick on till temp drops.


I have a door in front of the rack. Thats where the filter grill and fans are going.
 
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jepolch

Active Member
I have my server rack in the corner of the garage, then we built the 2 walls. The garage stays pretty nice as in temp. All the walls have insulation in them and the ceiling. But I am putting in a 12x12 inch filter grill on the bottom of the door and near the top of the door I am putting in two(2) 120 mm fans that are 120 Volt. Each moves around up to 100 CFM's. Plus I am hooking up a cool only thermostat, so we the temp goes up the fans kick on till temp drops.


I have a door in front of the rack. Thats where the filter grill and fans are going.
Sounds great. I guess my whole house is a server rack. :eek: It's just me and two cats and two dogs and they don't know what all my stuff is. To them the computers are furniture and I'm just the "can opener". :D
 

Sjacket99

Member
Sounds great. I guess my whole house is a server rack. :eek: It's just me and two cats and two dogs and they don't know what all my stuff is. To them the computers are furniture and I'm just the "can opener". :D

LOL. we have 2 dogs. I'm going to put my 12 leg antenna in the attic tomorrow and see what it does there. It's been pretty cold here. Plus we have snow here, so I'm not getting on the roof yet. It was 8 degrees out this morning.
 

ab cd

Senior Member
While the POTUS was in town for the G20 the temperature was 109ºF. Glad that's over! Makes getting on the roof uncomfortable/dangerous.

For few years, I worked in a deep desert area where summer mid day temperature used to be 131 deg F (55 deg C).
In Ontario, -22ºF (-30ºC).
From Frying Pan to Freezer..... :D
 

Turorit

New Member
Your range is less than it should be with an amplifier and not very long coaxial cable.
The first & foremost limitation comes from the terrain. Even the best equipment cannot increase range beyond the limit set by terrain. Only antenna height can increase the range limit to some extent.

I have pltted the maximum range achieveable at your location with antenna height 20 feet above ground, Two range curves are plotted, the blue one for planes flying at 40,000 feet & orange one for planes flying at 20,000 feet,

You should be able to achieve this range. Your home is blocking signal in some directions with antenna at current height/location. When you will mount your antenna on the tower, above roof line of your home, range should increase to some extent.

Please see your Maximum achieveable Range plot based on your terrain & 20 ft antenna height.

View attachment 574

I'm back, and I'm stumped!

A couple of months back I finally got around to raising the antenna onto my tower. Strange things happened....
The higher I had the antenna, the worse the performance was. My 2nd SDR & magmount whip antenna was still setup on the gutter and getting much better performance than the SDR 4m above it.
I removed the amplifier, worse again.
Swapped from the dipole to the pepsi-cantenna+amp. No change.
So I tried another spot, up the mast mounted on the chimney on the roof. Same result...
Switched off all my 2.4ghz wireless gear on the roof, still no better.
I gave up...

Gave it another shot today, built another cantenna. Tested it side-by-side with the magmount, similar/slightly better performance.
This time I decided to try mounting it on the chimney on the OTHER side of the house. Again it seems to be performing worse than the magmount sitting down on the gutter.

EDIT-attached pic:
Top window rpi2 is the cantenna on chimney (approx 4m above ground level). Second window is magmount on the lower gutter (approx 2.2m above ground level).
cantenna chimney2 vs magmount.JPG


Any ideas? :confused:

I'm thinking perhaps something to do with signal reflections from our tin roof?

Tempted to try a HPF or SAW to see if that might improve things.
 
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