Posts: 156
Joined: 7/25/2006 From: Topeka, KS, USA Status: offline
I happened to be back on that site getting circuitry ideas for video switching when I saw JP's post. I thought he might enjoy reading the article about the Goof Proof patch as overall it does a great job of explaining what is really inside of those square patch antenna's. Steve's tuning efforts are merely an extension of the bottom element inside of the patch to a length that optimizes performance. I was intrigued enough by the plans that I built one but have not yet tested it. By the time you pay freight on the SMA connector and purchase the other parts you are so close to the price of a patch it does not make a lot of sense to build instead of buy unless you want to squeak a little more gain out of the antenna. I suspect that all of the gain inprovement is in the fact that there is no lead-in. The SMA screws right onto the reciever. For now my little Omni disk on the plane and a patch affixed to the top of a metal rod 6' off the ground is sufficent for what we are doing.
I have my hands full rebuilding the E-Stik and probably will not get back to the antenna tuning topic for a while. When we crashed the E-Stik the camera was pointed skyward and the only indication of pending doom was the tail wheel swinging back and forth as the plane tip stalled. I want to be able to flip a switch on my 9303 and switch from the camera on the PTZ mount to a stationary one pointing forward.
Posts: 1151
Joined: 4/18/2005 From: Paradise, USA Status: offline
Thanks for the replys on the Patch antenna ground plane. 19 inches is also what I calculated, but that is pretty big to haul around and put on a tripod I wonder how much difference the extra ground plane would make ??? I have manufactured patches, both 14 dbi and 8 dBI, dont konw if its worth trying or not. It would take a pretty big gain to justify hauling something 19 inches square around along with everything else.
Posts: 66
Joined: 4/1/2007 From: Smyrna, GA, USA Status: offline
Hi, JP,
The ground plane size is absolutely not critical. Make it as big as you want and anything bigger than what is already included in the antenna will be better. Aluminum foil, foil-backed foam construction insulation board would all work. It would help to electrically connect your add-on to the antenna, but I don't think that matters too much. Hope this helps.
Posts: 1151
Joined: 4/18/2005 From: Paradise, USA Status: offline
Thanks Dave,
I will make something as big as is practical to transport. I am thinking of something with hinges on it, so I can fold the sides in, then it would be 19 inches long, but only 6 inches wide when folded up. That would fit with my gear just fine. I could electrically connect it to the patch, is the 1/2 inch height of the patch above the plate critical ? Or can I just mount the patch directly onto the plate which would be easier.
Posts: 66
Joined: 4/1/2007 From: Smyrna, GA, USA Status: offline
Hello, JP,
If you want to connect your extension of the ground plane to the factory antenna, you can electrically connect it to the factory ground plane. Or, you could just mount it as close behind the factory antenna back side as possible. I got excited when I first thought you were going to connect something to the radiating "patch" part of the antenna (the front part that the center contact of the coax connector is soldered to). Then I realized that you were referring to the whole antenna as the patch. It's okay, it's okay... Yes. just mount the antenna assembly to the ground plane extension. Hey--the folding sides idea is pretty clever.
To stay with the original thread topic--I tried to order a "Liftmeister" last month and Cedar Hobbies was out of them until December, they said. I guess everybody is realizing what good airplanes they are. Am I the only one who's happy that Friday is almost here??
Posts: 66
Joined: 4/1/2007 From: Smyrna, GA, USA Status: offline
Hey, JP,
Thanks for the thumbs up about Range Video. I placed an order with them Thursday (yesterday) and it came this morning at 10:30am. I'm looking at getting some video goggles that they have maybe next week. I've got some building to do--ordered two of their pan & tilt kits. Have a great weekend!
Posts: 156
Joined: 7/25/2006 From: Topeka, KS, USA Status: offline
Ok guys, I don't have any great pictures of my Stik reconstruction but I did shoot this picture last week. How can I convince you it was from my RC plane?
Posts: 66
Joined: 4/1/2007 From: Smyrna, GA, USA Status: offline
Bill,
I've been meaning to post something from our aerial photography project. The picture is a mosaic of several images shot from a Telemaster-electric plane. The camera was a Pentax point-and-shoot 5 MP looking straight down and triggered about every 3 sec. They were then made into a mosaic image using "autostitch" program. You can see the program tried hard but didn't get it perfect. Rooftop of the helicopter shed (top of image) appears to be influenced by a Kansas tornado. On the right, the road is not joined straight and appears to be zig zag. Altitude was about 600 ft and it was a little breezy that day. This is also the field where Steve flies when he's in town.
Hoping to make some video from another plane this weekend--last try, the servos all decided to jitter even before turning on the video transmitter. Murphy was an optimist.
Was the above really shot from your RC plane?? Cheers,
Dave p.s. if this picture appears twice, you can view it in stereo...
Posts: 156
Joined: 7/25/2006 From: Topeka, KS, USA Status: offline
Dave,
Great picture! I don't have any experience with autostitch programs but it does look like the stitching algorithm performed a couple of cross stitches.
Ok, I'm busted. It was not from an RC plane but the boom operator did have to elbow me away as I fired continuously with my D70. There is a local National Guard program for employers to go on courtesy refueling missions. I was fortunate enough to score a ride. We were over NE new Mexico last Tuesday and our "Recievers" were a couple of B1Bs.
Posts: 66
Joined: 4/1/2007 From: Smyrna, GA, USA Status: offline
Hello, Bill, and JP,
Since the Liftmeisters were out of stock at Cedar Hobbies, I've gone to the Sig Senior Kadet instead. It's a nice and roomy plane and should hold lots of electronics. It's almost finished, so look for some photos from me after Christmas.
A friend of mine helped me with some aerial video tests early in the month. I made a mount for a small camera--it looks down and left from the fuselage side of a Lanier Explorer 40. A 25mW transmitter was used and it gave marginal results until we had somebody track the plane with the antenna (didn't have time for one of those cool-looking antenna helmets, JP). A couple of photos are attached here showing our crude setup.
We had some really great weather a couple of weeks ago here in Georgia--it was over 70 and clear. I took off several days and did some more video flying. We taped a small 2.4 GHz camera/transmitter (2 mW) to my Mini Ultra Stick and flew all over our club property. One flight was pretty high and we could see a long ways. One of my friends tracked the plane with the receiver/antenna. I recorded it but don't yet have the computer setup to post the video. That's coming soon, too.
It's currently 45 F, cloudy and windy here in GA, but I hope it's nice where you guys are. I wish you all a very Merry Christmas, and I hope Santa Claus brings you plenty of R/C and aerial photography goodies....maybe even a Liftmeister ARF.
Posts: 156
Joined: 7/25/2006 From: Topeka, KS, USA Status: offline
Dave, (and all the rest)
Happy holidays to you too! We had a huge ice storm a couple weeks back and as soon as it melted we got nailed with about 8" of snow and 25mph winds. No outdoor flying going on here. Supposed to snow again today. Unfortunately I seemed to have lost my givash*&#@+ since about Thanksgiving. The E-GBS rebuild is at a standstill. Got some goodies for xmas that should relight the fire. It is good to see that someone is carrying on the AP faith when others are at an idle! My workbench has the Photo E-GBS, a Funtana X100, a Flybaby, and the gas stik to repair/rebuild to prepare for the 2008 season. And I want to put pontoons on my rat Alpha. If only I could afford to build as fast as I can crash and had time to do it!
Were you really just transmitting at 2milliwatts? That seems to be about the amount of rf generated by rubbing a nickel and a penny together.
Bill
< Message edited by wjglynn -- 12/26/2007 3:48:27 PM >
Posts: 47
Joined: 5/15/2007 From: , AUSTRALIA Status: offline
Great thread fellas, I just started doing videos, and will continue watching, but what caught my attention was very early in the thread.....I have HL Senior Telemaster, and I saw that the advert was easy to remove. Can you let me know how to remove the advertising please? It's been there long enough!
I started my airborne video experiments with a camera feeding a 70cm ham band (Oz) ATV transmitter. It still works fine, and the ST had space & weight capacity for the transmitter and 12v power pack
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All Forums >> Radios, Batteries, Clubhouse and more >> Aerial Photography and Video >> RE: the prefect platform for aerial photography 
RE: the prefect platform for aerial photography - 
I wonder how much difference the extra ground plane would make ??? I have manufactured patches, both 14 dbi and 8 dBI, dont konw if its worth trying or not. It would take a pretty big gain to justify hauling something 19 inches square around along with everything else. 
