Making an AIO Cam/VTX Less than 2.8 grams READY TO USE!


#1

Making an AIO Cam/VTX That is ACTUALLY Less than 2.8 Grams - The AKK S2/BS2: Shave it DRY!

NOTE: AKK S2 is on sale again in the AKK AliEx Store, [URL=“https://de.aliexpress.com/store/product/AKK-V2-5-8G-48CH-25mW-VTX-600TVL-1-3-Cmos-AIO-FPV-Camera-with-Clover/2959045_32806739542.html”]only $14.19 EACH![/URL]

[URL=“https://www.aliexpress.com/store/product/AKK-V2-5-8G-48CH-25mW-VTX-600TVL-1-3-Cmos-AIO-FPV-Camera-with-Clover/2959045_32806739542.html”][/URL]

A few weeks ago I Stumbled across the [URL=“https://www.aliexpress.com/store/product/AKK-V2-5-8G-48CH-25mW-VTX-600TVL-1-3-Cmos-AIO-FPV-Camera-with-Clover/2959045_32806739542.html”]AKK S2[/URL] on flash sale; it was half price on [URL=“https://www.aliexpress.com/store/2959045”]AKK’s AliEx Store[/URL]. That is a camera advertised at 2.8 grams for $US12.70!!!

Really amazing, I thought… until one of my friends in the WHOOP community pointed out that weight was without antenna. Somewhat disheartened, I waited for my cameras to arrive; and sure enough, when they got here (pretty quickly, though… AKK ships via ePacket) they weighed in at 4.2 and 4.28 grams each. Hoping to get somewhere close to the advertised weight of 2.8 grams, I started taking parts off and weighing them.

Whuff… as much as I prefer the 4-lobe CPW, that thing is HEAVY.

And that high-quality 26ga silicone wire with JST-SH plug is convenient; but it’s a third of a gram.

Please note that if you are going to remove this wire for lighter stuff as I did, you’ll have to remove this epoxy potting. This requires considerable care, and you have to apply heat with your soldering iron to remove it safely; there is a capacitor inside there just begging to be broken off if you try to pick the potting off cold.

You may not want to bother, especially if your install allows you to keep your wires under 15-20mm long.

For ultimate convenience, they include an adapter which will allow you to plug the S2 directly to any 1S battery with a MOLEX/Losi/Walkera connector; I highly recommend you use this IMMEDIATELY to test the unit and make sure it’s okay before you confirm receipt of product on AliEx.

NOTE: Be wary of the polarity, as there are many manufacturers who use this connector, and they like to switch (+) and (-) on the battery.

Okaaaayyy… now THAT’s what I’m talking about! IT ALL ADDS UP!!!

So looking at my other cameras, I spotted this spare Dipole off my BoldClash F-02; man, it sure is a lot lighter than that cloverleaf. But I think I can STILL do better.

Oh, HELL YEAH! Even I was surprised at how much that heat shrink adds.

Here I’ve installed the skinned dipole and 0.25mm shellac-coated wires; now my 4.25 gram fat piglet of a camera is a svelte 2.83 grams. but that STILL isn’t under 2.8 grams, dammit. Time for the final cut…

I know… the switch isn’t much. But I really don’t need it as the camera is easily accessible, and I can change the channels easily enough with a tweezer. I don’t change my channel very often anyways, so it was worth it to see if I could break 2.8 grams.

There you have it guys! An AIO Cam/VTX that is ACTUALLY less than 2.8 grams ready to use!

mnem OUT!
Now if I could only drop my own weight that easily…


#2

Brilliant work, @mnementh!!! Thanks for this write-up!


#3

Of course!

I meant to bring this over here when I posted it on my RCG blog, but I kindof was up to my elbows in kids home from school… LOL


#4

For an even lighter antenna, you can get surprisingly good results with a short piece of the coax used for RX antennae. Just trim the active portion down to about 12.9mm. I suspect the little metal barrel helps, but it works well enough without.


#5

Yeah, I saw that in the “Ultralight Whoop Build” video, but I tried it a while back with my E010 and found I had a lot more multipath noise and dropouts when flipping and especially when rolling/yawing into turns quickly. It really hurt my ability to fly, as I’d invariably lose video just as I was trying to find my track to make anything like a tight turn. For 15/100ths of a gram, I think the skinned sleeve dipole is the right mix of performance vs weight saving vs durability.

I know we have some folks who’ve done a proper dipole out of enameled magnet wire; but I’m finding that even with the protection of being right in the middle of my quad, my RX antenna is getting bent and breaking at the base from metal fatigue due to me having to straighten it once or more every flight.

What I really wish is that I could find/make an ultralight clover… if I could bring that in around 0.2-0.3 grams, I’d DEFINITELY be happy to eat the weight even on a Whoop.


#6

What are the size/dimension requirements for a clover?


#7

Exactly how big the current ones are unfortunately​, or exactly half of every dimension potentially.

You could use lighter weight wire, but the shape is extremely important so it has to stand up to wind and G loading without deforming.


#8

What are you using on the VRX side? With my Laforges + Triumph + TrueRC X-Air, I don’t see much difference between a sleeved dipole and just an RX style antenna. I had issues with drop-outs with a particular sleeved dipole that went away when I stiffened up the main feeder (which was limp enough that the dipole was flopping in the breeze)


#9

The size of the cloverleaf is pretty much defined by the resonant length of the active element, which in this case is the “curved” part of the lobe. In theory you could make it smaller; go 1/8 wave instead of 1/4 wave which I believe is the current design for a clover, but you’d have to design a matching balun which will most likely add more weight than you save by shrinking the antenna.

I’m pretty weak in the RX arena; a stock HP HD, as well as a little PCB 32-CH RX, an old RC320 and one of the early 40-Ch RC632 diversity RX that has the “1 weak RX” bug. I have several sets of Aomways and Triumphs I swap around as needed between my receivers.

I haven’t done much flying outside my back yard and a couple small local parks since the FAA crapped all over us; hence my renewed interest in “tiny flight”. Not really a lot of need for super-sensitive RX gear in my life as I’m never more than a couple hundred meters from my quad, so I haven’t bought any new RX gear for a while.

I’m actually rebuilding a couple of my bigger quads now that we’ve got a little breathing room until the next wave of institutional litigation smacks us down again.

mnem
"A wasted youth is better by far than a wise and productive old age."