LOL!
don’t make me break out batchpcb again. 8)
Gulp…
Jim Feed us, were all video hungry
I will see what I can do for video this weekend.
Jim Feed us, were all video hungry
Well the results were not as good as I was hoping for, but at least I gave it a shot. The setup is shown below. The rover and RC system are shown in the first image, and the video receiver is shown below that. Links to the videos are at the bottom.
What sort of range were you able to get with reliable reception?
I’m guesstimating your receiver and antenna were about 10 feet above ground level, and you were just using the little wire-stub antenna that comes integrated into the transmitter, right?
I’ve got a couple of projects and a trip coming up at the moment, but one of the projects on the “after I get back” list is to get a camera rover assembled from all of the parts that I’ve had sitting around ever since . Video feedback will be via amateur television, using a 100 mW transmitter on the 70cm 440 MHz band.
What sort of range were you able to get with reliable reception?
I’m guesstimating your receiver and antenna were about 10 feet above ground level, and you were just using the little wire-stub antenna that comes integrated into the transmitter, right?
I’ve got a couple of projects and a trip coming up at the moment, but one of the projects on the “after I get back” list is to get a camera rover assembled from all of the parts that I’ve had sitting around ever since . Video feedback will be via amateur television, using a 100 mW transmitter on the 70cm 440 MHz band.
As you probably know 2.4ghz wireless systems operate in the “microwave” region. So anything “in the way” will reduce the range, including water vapor in humidity. So my testing was with around 60% relative humidity. The range was not very impressive even with the antenna raised up higher. I had better range on a less humid day.
Also the antennas were both left in the horizontal plane. The problem with this arrangement is, with the camera on a pan and tilt the antenna can be pointed in ways that do not transfer power very efficiently. The antenna on the camera sticks directly out the rear of the camera in the horizontal plane. If the rover were driving away from the receiver the camera will receive better if the pan were moved to the left or the right. But if the camera were pointing forward the video would drop in and out. I wanted to try to bend the antenna on the camera up so it was vertical, and likewise point the receiver antenna up, to see if it improved the range, or just reliablilty.
I seam to remember reading somewhere that the camera’s antenna shouldn’t be fooled with, but I’m not sure where I read it. Anyway I got about maybe 100 feet of reliable video. The last time I tested I got twice that.
I want to investigate a better antenna on the receiver, and/or changing the orientation.
The camera itself wasn’t focused very well, and the display still has the protective film on it. Trying to video another video screen close by, while at the same time capturing the far off details… well it was an exercise in futility.
I remember in my communications class at the university that all antennas should be horizontal at this frequency. It is a human condition to point the antennas upward, so much so, that even on the back of some microwave routers a dummy antenna is used. It effectively makes the consumer believe that it will help while the real antenna is inside the enclosure. Even on the back of a PCI wireless card on a pc the antenna should be pointed horizontal as specified by the manufacture. Look at your cell phone next time most have a fake antenna because people like to stick them vertical.
You may or may not know that an antenna is a specific size for a reason. It is calculated to be ¼, ½ or full wave lengths so that transmittance and reception is achieved at its full potential. I am not sure if you tweaked with the length of the antenna but I recommend not doing so.
Best bet is to point the antenna in a horizontal position and leave the stock antenna at its lengths. Perhaps purchasing an after market antenna or using a parabolic dish calculated correctly for the size would greatly increase performance.
I remember in my communications class at the university that all antennas should be horizontal at this frequency. It is a human condition to point the antennas upward, so much so, that even on the back of some microwave routers a dummy antenna is used. It effectively makes the consumer believe that it will help while the real antenna is inside the enclosure. Even on the back of a PCI wireless card on a pc the antenna should be pointed horizontal as specified by the manufacture. Look at your cell phone next time most have a fake antenna because people like to stick them vertical.
lol funny…
You may or may not know that an antenna is a specific size for a reason. It is calculated to be ¼, ½ or full wave lengths so that transmittance and reception is achieved at its full potential. I am not sure if you tweaked with the length of the antenna but I recommend not doing so.
Yes I’m aware of the length of the wire being tuned for the frequency used. I didn’t do anything to them.
Best bet is to point the antenna in a horizontal position and leave the stock antenna at its lengths. Perhaps purchasing an after market antenna or using a parabolic dish calculated correctly for the size would greatly increase performance.
Yup, the www.boostervision.com guy has optional antennas for the receiver. Here’s a link…
boostervision.com/cart/scrip … Product=84