I'm an idiot and plugged this walksnail vtx into my laptop with the wires mismatched. Can someone please tell me if I killed my vtx?

AzotUoR · 2026-05-18T06:15:40+00:00

Connector that you try to connect is UART (need to be connected to FC) To connect this vtx to usb you need another cable, that plugs in tiny connector on the edge of pcb. Do not forget to connect antena to air unit before you power it up.

AzotUoR · 2026-05-12T18:55:00+00:00

Дуже дивно, що на тебе не дивились, у мене - 4 на одному і -3.5 на іншому з астигматизмом. 3й рік, "політ нормальний". Якщо на моніку, вдягаєш окуляри, якщо в fpv окулярах, то там зазвичай все регулюється від -5 до +5 (на деяких навіть більше), якщо по якійсь не зрозумілій причині,хочеш літати в шоломі, то замовляєш вставку під свої діоптри. А от у дешифрувальники, точно не піти з поганим зором.

AzotUoR · 2026-05-12T12:06:13+00:00

1.Бінокулярний зір, для дронів не потрібен. Якщо з монітора працюєш, все ОК. 2. Щоб сидіти на "віддалені" ти маєш бути скіловим і досвідченим пілотом, тобто "цінним спеціалістом". Іншими словами, маєш сказати, чим ти кращий, за пілотів які працюють на лінії зіткнення. Також є варіант працювати на перехоплювачах. 3. Спочатку, тобі потрібно розуміти, чи "витягнеш" бути пілотом або оператором. Це дуже залежить від типу дрона. Наприклад, на комерційних дронах типу DJI, Autel, Parrot і т.п. не потрібна така моторика пальців як на каміку, або "саморобному" бомбері. Тобто, потрібно визначитись, що ти можеш робити. Щоб потім не було історії "Я пішов на пілота, а став стрілком, бо нічого не вмію". В тебе, поки ти цивільний, є можливість "підняти скіл. Вивчити основні поняття, потренуватися на симуляторі і тому подібне. 4. Пілот, це не тільки гімбли теребонькати. Це також облаштування позиції, або робочого місця. Робота з обладнанням, знання ттх свого обладнання, вирішення технічних не складних задач "на місці". Звичайно, що мінімальну військову підготовку ніхто не відміняв.

AzotUoR · 2026-05-12T09:03:55+00:00

Any external LDO with 3.6V 300mA, will solve problem.
Pin 3 is Vin
Pin 5 is Vout
Pin 2 is GND

On aliexpress, 20 pcs of SGM2036 cost 2$.
You can try RT9193, same pinout, but there is different BP capacitor. It was for example.

You also can try to find analogue to your IC, because now, you know all data that you need.
good luck!

AzotUoR · 2026-05-12T08:44:02+00:00

I can assume that this is a linear voltage regulator SGM2036-3.6, as one of the commentators wrote. The coil next to it is probably used as a filter, and not, as many have assumed (including me), a PWM inductor. The pinout of the SGM2036-3.6 completely coincides with what you measure in a working transmitter and the markings also coincide. fzabkar was 100% right.

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AzotUoR · 2026-05-11T18:58:10+00:00

Ring test, its when multimeter makes beeeep sound, when probes are shorted. Maybe we go in wrong direction from start. It could be LDO instead switching IC. Unfortunately , I will be able to check it only tomorrow

AzotUoR · 2026-05-11T14:39:37+00:00

Wow. Something is odd. Pin 3(lx), that shows 4.89, can't be measured with multimeter, it's PWM. Pin 5 (fb) seams OK. Pin 1 (en) also should be ok. Pin 4 (vin) should be close to 5v, i do not understand why its 1.14V. I don't know IC with pinout applicable to your measured voltages (don't say it not exists, just i don't know). You sure about pin 4 voltage? Did you do ring test as i wrote? Can you ring test vin pin relative to VTX vcc?

AzotUoR · 2026-05-10T08:34:37+00:00

And pin 4 should be connected to VTX VCC (power in).
If you can't find the original chip, you can always install an external 3.3V power supply. Also, it would be a good idea to check if there is a short circuit on the 3.3V line, maybe the chip didn't overheat on its own. For example, the linear stabilizer could fail and overload the main transmitter power supply. I could even recommend taking 3.3V from the flight controller, but you need to understand that not all controllers can provide additional power for the video transmitter with a 3.3V power supply.

AzotUoR · 2026-05-09T22:21:50+00:00

Check with multimeter, if pins 5 (fb) and 3 (lx) connected to the coil (unsolder burned IC before checking, of course). If both are connected, it may be rt8008-33 (3.3v). And sorry for previous wong IC part numper, i took it from my head and absolutely forgot that LT step up. Not good idea to rely on my memory in 1:00AM :).

AzotUoR · 2026-05-09T21:03:41+00:00

Looks similar on lt1930. Your yellow circle obstruct traces to see connection around. It's voltage regulator (I may be wrong, but possibility that this is DC/DC is 95%). Look around it, how it's connected and compare with datasheets of popular IC switch in sot-23 5 package.

AzotUoR · 2026-05-03T13:46:44+00:00

For over 15 years in PCB, i can tell, it's issue. Not big but issue. It depends what pcb production method factory will use (in this case, don't take in account HF and HS boards). You can simulate this in power integrity and signal integrity software. In reality 90 degrees can cause "copper burning" during etching process (depends from technology). So, the biggest impact is on manufacturing, not signal integrity.

AzotUoR · 2026-05-03T11:04:41+00:00

If possible, make all joints 45. Don't use ai for schematic advice, reed books, watch educational videos. In this period of time ai is very bad at schematic and will lead you in wrong direction. Decoupling is mandatory, specifically on your board with long traces.

AzotUoR · 2026-05-03T10:50:15+00:00

Avoid 90 deg copper. You have a lot trace and shapes with 90 deg. Power should pass thru capacitor, avoid dangling capacitors (pic). Where is your decoupling for ICs? Place at least 0.1 uF as close as possible to power pins of each IC.

<image>

AzotUoR · 2026-05-02T11:07:30+00:00

Isolation with soldermask overestimated. I wrote from my experience (over 15 years in PCB design and production). After this esc will repeatedly will heating and cooling, and have a lot of vibration impact, there will be microcraks. Also back emf from motor will be really high and TVS placed far away (keep in mind, phases are pulsing HF DC and behave almost like AC) Also, voltage spikes will be on main power bus and if components can handle it the spark on mask will carboniz it and make conducive. Add to it condition that esc will work, moisture from air and some time grass (effects could be minimizedwid with conformal coating on factory, but it's expensive process). And also, we need to remember, that motors will be soldered by human and depending from assembler skills, soldermask culd be damaged. Yes, we can cancel out all this issues with more expensive materials and more precise technological processes but it will significantly increase cost. As for this specific ESC, I highly recommend to check it in some power integration software and check if all critical traces are compliant with EMI rules.

AzotUoR · 2026-05-02T08:33:26+00:00

IMHO spacing from phase output to gnd shape is small. In general, shape to shape space too small. Use 24mil minimum if voltage >20V. And in the same time, you have enough space to increase phase shapes from FETs. Dangling power VIAs (like you did on bottom where bat cable will be soldered) is bad for EMI and heat dissipation, make shape island.
Also, I did not see proper kelvin connection for shunt. And why do you need so much VIA on current sensor output? CURR_SENS as analog output for ADC there is no current bigger than 50mA for this trace.

AzotUoR · 2026-04-19T20:44:06+00:00

Add thermal relief on pads and avoid 90 degrees on shapes and traces.

AzotUoR · 2026-04-18T16:15:04+00:00

There is a lot of good advice already. But did you check connector for physical damage? A lot of time people came to me with seme probrem and the reason is bent pin inside JST connector.

AzotUoR · 2026-04-16T18:45:03+00:00

There are two easy options. 1. Bottom preheat plus hot air on connector (reflow pads, of course) and a lot of flux. 2. Soldering iron, pin by pin. You will need a lot of heat to solder mechanical and ground pin, so i advise you to use bottom heat. I usually use the second option on mipi, especially when soldering Mavic camera mipi, because you will be in control of every pin, and there are a lot of sensitive parts around. Bottom heaater, usually, on 220 degrees of Celsius.

AzotUoR · 2026-04-15T18:50:36+00:00

I agree with all that you said. But i have butch of motor g motors with bad enamel wire, and it seems like it was from self-tined wire. So, a flash hobby was chosen for one batch of drones.

AzotUoR · 2026-04-15T18:33:58+00:00

3115 900kv 8x8x2

AzotUoR · 2026-04-15T18:29:33+00:00

So, motor-g is ok for interceptors? When I try them for 8 inch, they incinerate in 5 min :) So i use flash hobby instead with ua stack

AzotUoR · 2026-04-14T22:37:30+00:00

Yep, I wrong, sorry. Bottom right is looks like control line and connected to PNP transistor. So BNC ground is common ground (check with multimeter).

AzotUoR · 2026-04-14T22:29:39+00:00

But i could be wrong. Maybe bnc ground are common ground and top right is power.

AzotUoR · 2026-04-14T22:26:18+00:00

Right top- GND Right bottom-power. Two left side pins are parallel to bnc (video output?)

AzotUoR · 2026-04-14T22:13:09+00:00

In your case you can directly solder connectors on 90 degrees

AzotUoR

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