Posted by dalbert02 |
Oct 08, 2011 @ 09:27 AM | 157,519 Views
Just a few pics of my tricopter and quad copter. The quad is waiting on a hoverfly pro board. Contrary to some advice, I have had better luck using vibration isolation and dampening than hard mounting. Perhaps it is a delicate balance between too loose and too rigid? One place where no slop is tolerated is the yaw mechanism. I had about 1mm of play around the bearings in the square tube. I filled the gap with Hysol, and the wobbles went away.
...Continue Reading
Posted by dalbert02 |
Dec 10, 2010 @ 11:25 AM | 159,481 Views
Here are some pics from Coco Cay, also known as Little Stirrup Cay, one of the Berry Islands in the Bahamas. I was asked to take some aerial pics and vid as part of a surgical transport team for situational awareness. The event was sponsored by Budwieser, ESPN, and Royal Carribean. This was one of my most difficult missions. I had to pack my equipment to survive international flight, being packed on planes, barges, and under hundreds of pounds of medical equipment on trucks. In addition, the winds were blowing 20-25 knots straight on shore, which required a tail wind landing on a 100 foot beach area with the sun directly in my face as the plane came in. Needless to say on my first landing attempt I stalled about 30 feet out over the water at an altitude of 10 feet. Somehow I recovered but there was some significant pucker going on which made the subsequent flights even more nerve racking. No hobby store around for several hundred miles if anything failed! Special thanks goes out to Dr. Michael Nash as he is also a full scale pilot and offered advice, held equipment and help me launch and recover. I think I have him hooked!
Posted by dalbert02 |
Apr 03, 2010 @ 10:20 AM | 159,502 Views
I have finally finished my portable ground station. My goal was to be as portable as possible, yet still able to achieve semi-professional results on the cheap. Installed equipment includes:
Pelican Case
1600 NITS outdoor viewable monitor
500Gb HDD DVR
Kramer audio/video distribution amp
Pyle composite video distribution amp
Amberly composite to VGA converter
KeyWest VooDoo 10bit Time Base Corrector
Oracle diversity reciever
Black Widow 2.4Ghz diversity reciever
Lawmate 2.4Ghz reciever
(2) 2.4 Ghz Hyperlink 8db circular polarized patches
(1) 2.4Ghz Peak Antennas 6db Colinear Omni
Now that it is finished, I really want to move to 1.2Ghz or 900Mhz. I guess that is what happens when it takes more than 2 years to complete a project! It is made from industrial 3m velcro and pieces of aluminum from Home Depot.
Posted by dalbert02 |
Aug 19, 2008 @ 06:35 PM | 160,376 Views
Posted by dalbert02 |
Jan 11, 2008 @ 02:56 PM | 162,039 Views
I finally finished tuning and adjusting my Rf amplifier. I needed to order new slugs for the Bird to measure accurately, but it was worth it. Attached are some pics. With a MFJ 6m dipole, I am usually less then 1.5 SWR (it depends on location) and I am getting almost 25W max out!
Posted by dalbert02 |
Oct 23, 2007 @ 09:15 AM | 161,898 Views
On rcgroups, my favorite forums are UAVs, Aerial Photography, DIY Electronics and FPV. Over time, it has become apparent to me, that increased rf power would be desireable to increase range and or boost the signal if some erratic glitching were to occur. JettPilot and Thomas Scherrer both built rf amps and I felt I should consider it. Sadly, I am not as talented as they are in rf design and had to purchase something 'off the shelf'. First, I wanted to see what my current rf levels were out of my Futaba transmitter. I measured very little power indeed! At first I tried using just my oscilloscope and got 3.4v p-p into a 50 ohm load. 3.4/2=1.7v peak. 1.7x.0707=1.2v rms. 1.2vx1.2v/50ohms=28mW rms. That can't be right I said to myself. So then I built an small rf rectifier (just a diode and a cap) and measured 1.7v dc with my fluke dvm. Hmmm, same thing. Ok, how about a Bird meter? Sadly, the bird I had access too does not measure such low wattages accurately. I tried adjusting the rf module myself, but I couldn't muster up that much more power without noticing distortion on the o'scope. Still thinking something must be wrong, I used a service monitor in spectrum analyzer mode and measured 17-19db which is about 50-80mW. I read somewhere that the voltage drop of the diode can effect these low power measurements, so I guess things were correct all along. I just couldn't believe it because everyone says that these transmitters put out 500mW to 1W. So... rf amp time it was.
I settled on a Mitsubishi rf power module from rfparts.com along with a circuit board manufactured by Down East Microwave. A few caps, a voltage regulator, a box with heatsink and I was in business. Measured output was 40db or about 10 watts. Perfect!
My next step it to clean it up a little. I would like a power switch, reverse polarity protection, a power LED, an rf power LED or meter, and a selector know that increase the power gradually. Say, 500mW standard, 1W for long range, and something more for extreme emergency situation.
-dav
Posted by dalbert02 |
Oct 02, 2007 @ 11:42 PM | 161,436 Views
I bought a F3A shock flyer as I had totally destroyed my Super Star Shock Flyer over the course of a year. I took the F3A and used it as a template to cut some new foam from BPHobbies.com. Next, I painted her up with flourescent paints using a paasche model H airbrush. Finally, I installed some black light UV LEDs. She sure does glow brightly!
-dave
Posted by dalbert02 |
Aug 30, 2007 @ 07:12 AM | 161,385 Views
For some reason not all my pictures come out well. However, once in a while everything seems to work.
Posted by dalbert02 |
Aug 12, 2007 @ 09:45 PM | 161,264 Views
Just some pics of the ground station. Laptop running AGWTracker, AGW Packet Engine, APRSPoint, MapPoint, Garmin MapSource & nRoute.
Posted by dalbert02 |
Aug 01, 2007 @ 02:47 PM | 161,246 Views
Here is screen capture of the RC-CAM Inspire board.
Views: 383 
Views: 344 
Views: 329 
Views: 337 
Views: 335 
Views: 329 
Views: 389 
Views: 339 
Views: 741 
Views: 645 
Views: 630 
Views: 583 
Views: 613 
Views: 641 
Views: 761 
