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Posted by devinvagt | May 05, 2016 @ 12:29 AM | 2,976 Views
I have been testing a new lemonrx receiver+ stabilizer combo in my sub 250 gram plane and I've found it works well in close. BUT... I've been getting a loss of control out a farther, say, past 0.25 mile/ 0.4 km . In two cases, I still had pretty good servo control to land, but no motor response. So I did some range testing in my back yard and I was able to replicate this situation pretty reliably. It comes down to how the receiver failsafe handles signal loss.
When the lemonrx receiver loses the signal, it sets the throttle to zero. No surprise there. But when it reacquires the signal, it does not restore throttle to its previous value. Rather, you have to move the throttle stick up and down for a while, sometimes for as long as 10 seconds, before you are given back throttle control. During this time you have varying amounts of servo control, which is a big help when you're trying to pick a spot for an emergency landing. However, in the most recent case I was flying over a lake and had to land in the water, so there were no good spots to be had (I swam out and fetched the plane -- it's OK now. )
So what to do? A mini-shootout, of course. I ran a range test setup with the diversity lemon rx combo, a diversity lemon rx receiver, an orange rx r615x, an orange rx r620, an old spektrum ar600 with a couple of split-v dipole antennas( a la Ibcrazy) attached, and a brand new spektrum ar610. I should add that my transmitter for this test was a spektrum DX6i...Continue Reading
Posted by devinvagt | Apr 24, 2016 @ 11:36 PM | 1,659 Views
I 've been trying out some different mini - cams for my sub 250 gram planes, and I thought I'd share my findings. I checked out four cams, in ascending order of price:

Eachine 700TVL 2.6mm Lens 1/3 CMOS 110 Degree $14
Aomway HD Mini 1/3'' CMOS 600TVL 2.8mm $18
Tarot 520TVL FPV 1/4 120 Degree Wide Angle Lens $31
RMRC-Pico wide v2 520TVL $45

and in ascending order of weight ( with cable attached, cam is no good without a cable! )

Tarot 7g
Eachine 10g
Aomway 15g

The smallest, lightest cameras tend to be more expensive by a wide margin.

And by ascending FOV:

Eachine 100
Aomway 110
Tarot 120

The Aomway is probably the best camera overall, a very sharp picture, good color and not too expensive, but also being the heaviest, if you can call 15g "heavy". Also, it seems from the aspect ratio that it is sending PAL video, despite the box's assurance that it's the NTSC version. It also tends to over-expose rather than under expose, which is an asset for FPV flying.
The Tarot and RMRC are the only ones light/ small enough to go on the tail of my HK swift mini without screwing up the CG and aerodynamics. Both are 520tvl, and I noticed the difference after using 700tvl cams for a little while. They seemed a little blurry and I was convinced they were out of focus. Nope, they're just a little lower resolution. Still quite useable, but unless you need the smallest, lightest cam you...Continue Reading
Posted by devinvagt | Aug 06, 2015 @ 09:22 PM | 1,495 Views
Accidentally destroyed a surface mount component while changing the 5v regulator on my remzibi OSD to a recom r785.0-1.0. It's a drop in replacement for a standard 7805 with much better efficiency-no heatsink neeeded! I think later versions of this board incorporated a similar item. I tore off part of the trace along with an unidentified surface mount component. Bad bad bad.