After seeing all these avatar micros (ph2t), ordered a VRX + 1S lite combo. A <8g, <$90, single board digital package that , includes HD dvr is awfully attractive for micros. I had a little trouble deciding what build to put it in, a 2.5" phantom with 1105 motors, 85 whoop 1102/1103? motors, but in the end based on the frames/motors I had, decided on a light simple 2S 3" cruising setup.

The build was quite uneventful, which is a good thing. The walksnail VRX/VTX was relatively straight forward and easy to setup.

FC: I chose the Betafpv F411 1-2S ELRS AIO. I quite like this board for 2S builds, less than $40 with built in ELRS and 12A ESCs, maybe the cheapest ELRS FC. I also like how they moved the USB plug off the board, you only need to connect a soft tiny SH1.0 connector. I have used this board on a handful of builds including some 4" picks and so far not a single issue (unlike Betafpv's 2-4S boards which more than 50% of mine have failed).
If you use motor plugs, they include both top/side orientation and you solder on the ones you need. Plugs are relatively easy to solder, but if you are soldering thicker motor wires, this board is a major pain. I do think I found a very good solution though, tips below.

Power Supply: I tested the walksnail on the bench with 5v and in standby/25mw mode it easily drew 0.5-0.8A and when set to higher transmit power it was pulling over 1A. Per Betafpv support, the 2022 version of this FC has a 5v regulator rated for 2A, and they confirmed it was suitable to power the walksnail VTX. If you have the older version of this board though, I would be wary as support previously told me the older board was only rated for 0.8A. Also if you are power off 1S, the step up amp rating is likely lower.
Also one oddity about this board, I believe all the 5v pads are powered when USB is connected, so be careful. I did add a 5v pigtail so vtx power can be disconnected, but then realized the female plug I soldered on was actually ph1.25, maybe on the next build.

Frame is Betafpv HX115LR pick frame, 1202.5 6000 kv motors, and Gemfan 3018 biblades
Haven't decided if I want to top or bottom mount the battery, so add a few more grams for battery pad/strap.


Camera does not come with any mounting holes so using a 2 part tpu mount. A ring piece loops over the barrel and has nubs that slot into the side tpu mount and can be rotated.



The antenna ufl is located right next to the mounting hole, added a TPU holder to keep it screwed down.




Just a short maiden in gale force winds. Using an old set of headplay goggles the image looks super especially on a larger screen. Not sure if the aspect ratio is a little off, things look a little distorted in roll. It was flyable, but did feel some latency although it could also be the weaker motors.

Edit: Forgot there was one minor issue. The 1S lite VTX I received came wired with the grey/white wires flipped. So RX/TX was flipped if going by the colors of their manual/labels.

I have very bad eyesight, clumsy fingers, and mediocre soldering skills, but enough patience. Soldering larger wires on cramped motor pads usually results in a lot of frustration and resoldering. I think Betafpv made it worse by making these pads longer, as there is now even more surface area only a micron away from the next pad as opposed to circular pads where they only come together in one tiny spot. 
In this build, I got it on the first try without needing to resort to any amount of cursing or reworking. Granted the wires were not too thick, but I think the following method helped a lot.

1) Solder the middle wire to the bottom side. I know there are those who do not recommend using the through holes, but in this situation it helps to hold the wire in place very well.


2) Check for continuity, between middle and side pads.

3) Flip board over and solder the two outside pads.

thats a good savety tipp for beginners.
i progressed by the best solder and additional liquid flux, all flows where it should regardless how tiny the cap is with enough flux :-)

nice build weight :-) happy maidenflight :-)

Nice build!

I like that frame. I’m looking forward to hearing how it flies without gale force winds.

I’d also love to hear your thoughts on those motors and bi-blades. I haven’t had much luck with 12xx motors or bi-blades, but it seems that plenty of others do. Perhaps I’m not making builds light enough?

Can you share a link to that cam mount, or are you willing to share the file if you designed it yourself?

Sure here is a link to the TPU prints in tinkercad (probably easier if you anyone wants to tweak to their liking). Nothing special, but the designs are functional and light.
HX115LR Walksnail

2S, underpowered motors, and bi-blade setup don't make for great flyers, but as a lightweight cruiser I think they are good enough and easy to get long flight times (easy 15+ min). I have several similar builds using 1103 motors, which actually have slightly more stator volume than these 1202.5s and weigh less, so I suspect it will not fly as good as the 1103s. However these RCinpowers were very smooth on the bench even though they are used (I moved them off a 85 whoop that I never flew much). Will have to fly them back to back to see, but HD video is clearly more enjoyable to fly so.

But yes, I think lighter setup is key for 1202-1204. I prefer triblades, but with these smaller motors don't handle 3" triblades well. And in terms of bi-blades, I had terrible imbalance problem with the HQ ones, and actually had to balance them to get them to fly on the lighter setups.

I did have a 3S 3" pick with 1204 motors running triblades, and that flew very nicely, but I don't know what happened. Replaced some delaminated arms, but it never flew the same, and didn't get back to figuring out what changed. My smallest HD build was 3.5" and that size flies so well for my style of flying I guess all my sub 3.5" kind  of sat on the shelves, but the walksnail changes the equation and time to go back to 2.5/3".

I saw you were trading out your 1207s, I have a draw full of the RCinpower ones (maybe because they were so shiny). They sucked batteries dry quickly on my heavier 3" builds, but I found they are great for 3.5". Plenty of power, but still get close to 4-5" min and no problem handling the 3.5" props as far as I could tell.

Thanks for the link to the 3d print files!

I haven’t tried any of the RCinPower 12xx motors, but I do love all of their motors in sizes that I have tried.

I think you might be right and I’m judging 12xx motors on unfair terms- I tend to build overpowered, overweight things that can take a hell of a hit. I’m a fan of high pitch props, raw power, and I’m not much of a cruiser.

I will admit that I am biased against 12xx motors because I have burned a number of them out while staying within tolerances- but still, I might have been asking too much out of them. I might have to build a lightweight toothpick with them and see what it can do before I continue to bash them.

I do have a prop balancer that I use on my rc planes and larger props, maybe I should use it on smaller props as well.

I’ve seen a number of builds with 12xx motors that fly like a bat out of hell, I just can’t seem to make the same.

I don’t crash quite as hard as I used to, so, a lighter frame is definitely an option now.

Your build looks like it could fly quite well- I am definitely looking forward to hearing about how it flies in better weather.

Also, I really wish there were more flight controllers available with external usb jacks like that betafpv board. There are a few Diatone ones, and a couple others- but I wish it was more common. It would make a number of builds much more plug-in friendly. It’s a pretty awesome feature.

Nice build. Good Job!

1202.5 is quite weak for 2.5", so becareful on 3". But, you are great builder and its only 52g.
6000KV should allow 3S. Probably want 90% throttle limit.

About micro motors that I have:
RC1204 5000KV pink on 3" 3018 running 4S.
GepRC1204 5000KV gold on 3" 3018 running 4S. Ordered plastic screws to save 2-3g.
But weird build is HM1203 11000KV on 2512 3S. Yeah 3S. Very zippy. Estimate 18-20A. Somehow they haven't melted.

Calm morning and squeezed in a few packs. Not for agressive flying, but it cruises okay. I think I prefer the 1103 motors for this setup. I noticed less prop stutter with 1103s, or maybe HD is just showing up more clearly. Also vibrations at full throttle, but had the same for the 1103s and probably due to prop imbalance/light frame combo (where did the tpe setting go?). Flight time though was seriously disappointing, less than half the time of a similar 1103 analog setup with the same weight.
Roughly 3 minutes with a 300mah pack and 7.5 minutes with a 850pack; on the 1103 analog I get 6.5/18 minutes using the same packs. I guess in addition to the VTX transmit power, there is also the H265 encoding/DVR power draw penalty (like the Tarsier or other split cameras). But I suspect the 1202.5 are also less efficient as well.


VRX Notes:
Changed the goggles aspect ratio to 4:3, but roll distortion was worse so seems 16:9 is the correct ratio. I guess the headplay HDMI scales the image to a slightly different ratio (I think it is a 1200x600 screen). I may try flying on my 27" PC monitor...

Reception at 25mw stock antennas was fine for flying around the yard. Definitely better than my analog setups that tend to static up behind the house. There is a trouble spot where I cross my home router, even DJI struggles at this point, and the walksnail also stuttered, but bumping to 200mw it seemed fine.

Did notice I can see both props and camera mount so mght tweak the mount to push the camera forward a little.


FC Notes:
The 2022 version has lost its LEDs, too bad the older version had one on the left corner and on the right which looked nice. Also they replaced the ufl plug with a single wire, I already got some RF signal warnings just flying around the house. The pads are there so I guess it is possible to solder on a better antenna.
And for the sh-USB connector, I am also surprised not more whoop boards have this. It just makes mounting so flexible.

Now I can't seem to find where I put the avatar USB cable to download the footage...

Edit: Leds are still there, just not configured by default.

(05-Mar-2023, 04:34 PM)romangpro Wrote: Nice build. Good Job!

1202.5 is quite weak for 2.5", so becareful on 3". But, you are great builder and its only 52g.
6000KV should allow 3S. Probably want 90% throttle limit.

About micro motors that I have:
RC1204 5000KV pink on 3" 3018 running 4S.
GepRC1204 5000KV gold on 3" 3018 running 4S. Ordered plastic screws to save 2-3g.
But weird build is HM1203 11000KV on 2512 3S. Yeah 3S. Very zippy. Estimate 18-20A. Somehow they haven't melted.

Yes the 1202.5 definitely feels a little weak, won't be able to test them on 3S in this build though. I may try to switch to 2.5" for better performance, but flight times would likely be even worse.

You definitely run more voltage, my 1204s don't see more than 3S, and my HM1203 also on 3S, but the 5500kv version

For me, I put the camera a little further forward, then the props are barely in the picture:





(HM 1102/10000, FC Goku 1-2S, M10 Nano GPS, cruising flighttime 4-5min with 2S/450)

(05-Mar-2023, 08:00 PM)radla Wrote: For me, I put the camera a little further forward, then the props are barely in the picture:

Nice, do you have the non-lite version, the camera looks a little different, but guess it is just the case. It seems I would need to push forward the camera quite a lot. How do you like the 1102 motors? And how do you find the range of the VTX, have you flown it out far?

I couldn't find the USB cable, so this is the DVR footage from the VRX. This was the second flight, flying with 850 battery in calm conditions.

Yes, its the not the lite version. The maximum range i testet so far was about 500m without any issues.
When i fly through bushes/trees, even with 50MBit, i still have problems with blurry image. (also at close range.)
Yours is definitly faster, than my with the underdimensioned 1102s!

I think flying speed has more to do with camera angle as these cruisers are flying at low throttle, but yes larger motor does give better prop response. Your motors are higher kv, so maybe better for 2S. I think my motors on 2S just a little too weak for this prop, may try some 2.5" props or otherwise switch out the motors (but not sure I want to resolder those wires...).

So 500m on the 350mw setting? And is there any advantage of the 50mbps over the 25mbps, do you notice better image?

(06-Mar-2023, 03:32 PM)mstc Wrote: And is there any advantage of the 50mbps over the 25mbps, do you notice better image?

It helps a bit when flying through detailed bushes, but in some places it is unfortunately unflyable. It seems that this is not a typical scenery for walksnail.
In any case, it is more detailed, because when converting with the hd_fpv_video_tool, the created files are significantly larger than before

(06-Mar-2023, 04:25 PM)radla Wrote: It helps a bit when flying through detailed bushes, but in some places it is unfortunately unflyable. It seems that this is not a typical scenery for walksnail.
In any case, it is more detailed, because when converting with the hd_fpv_video_tool, the created files are significantly larger than before

For larger file you are referring to goggles file or the onboard file? I found my USB cable, have to give it a try.

For OSD overlay I used the ws-osd-py tool, not the best interface. Will give the other tool a try.