All the things is getting costlier today, however radio controllers appear to be transferring in the wrong way. We now have a completely practical ExpressLRS radio for simply $35: the Radiomaster T8L! It’s a compact, light-weight, screen-less controller designed particularly for budget-conscious FPV pilots, inexperienced persons, or anybody who merely wants an inexpensive radio for FPV simulators and tiny whoops.
Study extra about radio controllers on this purchaser’s information: https://oscarliang.com/radio-transmitter/
The place to Purchase?
Get the Radiomaster T8L from:
It comes with a USB cable, guide, some spare gimbal springs, and stickers.
Specs
- Constructed-in RF Module: 2.4GHz ExpressLRS (SX1281)
- Frequency Vary: 2.400GHz–2.480GHz
- RF Energy: Adjustable 10dBm (10mW) to 20dBm (100mW)
- Corridor-effect Gimbals
- Helps as much as 10 channels
- Battery: Two 18650 cells (not included)
- Charging: Constructed-in USB-C charging
- Configuration: Browser-based UI through USB-C
- Colours: Blue, White, Gray
- Measurement: 165 × 120 × 70 mm
- Weight: 302g together with battery, 204g with out battery.
Measurement comparability to a full measurement radio – Left: T8L; Proper: TX15
Design and Construct High quality
The Radiomaster T8L seems to be closely impressed by the DJI Distant Controller 3 (RC3). It shares many similarities, together with the colour theme, total kind issue, detachable sticks, battery degree indicators, and even the swap structure.
Left: Radiomaster T8L; Proper: DJI RC3
Left: Radiomaster T8L; Proper: DJI RC3
No Display? No Drawback!
The very first thing I seen was the entire lack of a show. As an alternative of utilizing EdgeTX and having a built-in display screen like all of the mainstream radios, all configuration is dealt with by way of Radiomaster’s web-based configurator, which you entry by plugging the radio right into a PC through USB-C.
As somebody who primarily makes use of radios with a display screen, I discovered this slightly worrying at first. With out a show, you don’t have any fast strategy to test:
- Your present radio settings
- Telemetry reminiscent of RSSI, LQ, or battery voltage
And sure—you’ll be able to’t create a number of profiles for various fashions. For many who personal several types of plane will discover it limiting.
That stated, for some folks it isn’t a dealbreaker. In actual fact:
- There’s a devoted bind button
- The web configurator provides loads of settings and customization
- Most choices solely should be modified as soon as throughout preliminary setup
I do assume Radiomaster may take this additional. A smartphone app appearing as an exterior show, would make area use much more handy with out growing {hardware} price.
Controls and Swap Structure
Regardless of being an ultra-budget radio, the T8L packs a surprisingly full set of controls:
- Two hall-effect gimbals — comparable management really feel to DJI RC3 with matching gimbal pressure
- Trim buttons (mild up when not centered)
- Two momentary buttons (SA & SD)
- Two 3-position switches (SB & SC)
- One rotary dial (S1) — no mechanical middle detent, however an audible beep at middle (when powered on)
- One 2-position latching swap (SE)
- USB-C port for each charging and configuration
Sadly, the T8L doesn’t have a coach port.
Gimbals
The inventory hall-effect gimbals are a nice shock. They’re clearly not in the identical league because the premium AG01 or AG02, however they really feel higher than a budget potentiometer gimbals in lots of price range radios I’ve examined.
The stick ends are fairly sharp and go away marks on my thumbs after an intense session—however the upside is great grip.
Stick size isn’t adjustable, it’s nice for thumbers. For hybrid pinching, it’s usable, however I do want they had been a bit longer. Luckily, the gimbals use M3 threads, so you’ll be able to maybe set up longer aftermarket stick ends. The onboard stick holders on the again are giant sufficient to carry longer stick ends as effectively.
I’ve been instructed the T8L is suitable with the AG01 Mini Gimbals, however I haven’t tried putting in them myself. Nonetheless, given the excessive price of AG01s, I’m undecided they make sense in such a budget-focused radio. Personally, I believe the inventory gimbals get the job performed simply high quality.
Inner Antenna & Vary
There’s no exterior antenna on the T8L, which helps maintain the radio compact. As an alternative, it makes use of a small ceramic antenna that’s built-in on the mainboard (you’ll be able to spot it because the pink chip marked “C3”). This setup is completely high quality for informal pilots, however you shouldn’t anticipate the identical vary or sign reliability as full-size radios just like the Radiomaster Boxer or TX15, each of which use full measurement exterior antennas that may be positioned for optimum alignment.
WiFi Antenna and a couple of.4GHz Ceramic Antenna
The RF energy is proscribed – the T8L maxes out at 100mW. Clearly, it’s not designed for long-range or demanding situations the place sign reliability is essential, however is greater than sufficient for:
- Indoor flying
- Tiny whoops
- Park flying
- Brief-range freestyle
Personally, I don’t think about this a flaw—it’s clearly an intentional design tradeoff to maintain the associated fee low and the shape issue compact. What I do want for, although, is a UFL connector for the antenna. That may permit customers to improve to a greater antenna and even route an antenna externally for improved efficiency.
With a correct antenna, even a 100mW ExpressLRS hyperlink can obtain a number of kilometers of vary (one thing I’ve personally examined). It’s a missed alternative, as a result of including a UFL would have opened the door for simple, secure, user-friendly upgrades with out growing price considerably.
Person Expertise and Management Really feel
The T8L feels pure to carry whether or not you’re a thumber or a hybrid pincher—although I do want the stick ends had been barely longer for pinching. The gimbals are surprisingly good for a price range radio. They’re easy, adequately exact, and I haven’t seen any jitter on any channel, which is nice. Hopefully this implies no deadband is required in Betaflight.
Out of the field, the spring pressure felt a bit too stiff for my style, so I loosened them. You possibly can entry the stress screws by peeling again the rubber grips on the rear and inserting a 1.5mm hex driver by way of the holes—no have to disassemble the entire radio.
Nonetheless, the vary of spring adjustment could be very small. Even the bottom pressure really feel barely too stiff for me. And for those who loosen the springs an excessive amount of, the gimbals begin to make a rattling/clicking sound close to middle stick as a result of lack of pressure, the gimbal mainly “floats” with nearly no resistance.
Luckily, Radiomaster contains spare, longer springs within the field. These longer springs present lighter pressure and a softer, smoother gimbal really feel.
That stated, a phrase of warning: changing the springs is NOT simple. You’ll want to totally disassemble the radio and the gimbals. The elements are tiny and fiddly. It’s doable, however requires endurance. If you happen to favor a looser gimbal really feel like I do, the modification is value it—the advance is noticeable.
I’ve additionally seen complaints on-line in regards to the problem of reaching the highest 3-position switches. Personally, I don’t discover this to be a problem. I suppose it is determined by how lengthy your fingers are. However actually, for those who battle to succeed in switches on a compact radio like this, you’ll doubtless run into the identical situation on most fashionable transmitters, that are bigger and have switches spaced even farther aside.
Energy and Batteries
Beneath the rubber grips on the again of the T8L, you’ll discover slots for 2 18650 batteries. These should not included, so think about the associated fee for those who’re on a good price range. If you happen to want suggestions, listed below are my examined favorites: https://oscarliang.com/best-18650-li-ion-battery/#Outcomes-and-Suggestions
To summarize, my high decisions are the Molicel M35A and Sanyo NCR18650GA. If you happen to’re ordering the radio instantly from Radiomaster, their 3200mAh 18650 cells are additionally an amazing possibility and prevent the effort of ordering batteries individually:
These 18650 are detachable, so you’ll be able to swap them on the go, which is nice for lengthy flying classes. Not sizzling swap although, it’s a must to flip the radio off. The 2 cells are linked in sequence, that means the radio is not going to energy on if just one cell is put in, two cells are required.
Charging is completed by way of USB-C at round 8–9W most. On paper, charging a pair of 3000mAh cells from empty would take simply over 3 hours.
The radio itself is extraordinarily environment friendly due to the shortage of a display screen and its comparatively low transmission energy. Throughout my tesitng, it drew round 1W at most, that means a full cost (3000mAh cells) can final roughly 25 hours of use. If you happen to fly 3 hours a day, you might realistically get by way of a whole week on a single cost!
Configuring the Radiomaster T8L
The Radiomaster T8L makes use of a web-based configurator, and I’ve to say—it’s surprisingly effectively designed and simple to make use of. Even inexperienced persons ought to discover the interface simple.
Utilizing the Radiomaster Internet Configurator
To configure the radio, you:
- Maintain the M button and Energy button for 3 seconds to show it on
- Plug in a USB-C cable
- Open the Radiomaster Internet UI: https://radiomaster-rc.github.io/RM-Internet-Web page/Connection.html (I made a shortened URL, simpler to recollect: https://bit.ly/t8l-config)
- Choose the COM port and click on Join
As soon as linked, you’ll be able to entry:
- Gadget settings: quantity, sign/energy warning, firmware model, swap conduct, and many others.
- Channel monitor, settings, mapping and mode (1,2,3 or 4)
- ExpressLRS RF settings (comparable choices to ExpressLRS LUA script), you’ll be able to change RF energy, allow WiFi, change packet price and swap mode and many others.
- Stick calibration
- Firmware updates for each radio and Inner RF module
It doesn’t supply as many settings as a full EdgeTX radio, however for many pilots flying quadcopters, the out there configuration choices will cowl nearly the whole lot you want. My solely actual criticism is that the configurator URL is lengthy and never very user-friendly—that’s why I made this shortened URL: https://bit.ly/t8l-config
Setting ExpressLRS Binding Phrase
As a result of the T8L makes use of a built-in ExpressLRS module, you set the binding phrase utilizing the acquainted ELRS Wi-Fi technique:
- Allow Wi-Fi below the RF Settings tab
- Hook up with the radio’s Wi-Fi hotspot
- Open 10.0.0.1 in your browser
- Enter your binding phrase and click on Save
This works precisely like configuring another ELRS TX module or receiver.
Turning a Momentary Swap Right into a 2-Place Swap
I usually arm my drones utilizing a swap on the top-right nook, however the T8L doesn’t have a latching swap there. As an alternative, it solely has a momentary button—so I reconfigured it to behave like a 2-position swap.
Right here’s the way it works:
- Press as soon as → HIGH
- Press once more → LOW
There’s no bodily indication of the swap place, however the radio supplies audio cues if you press it:
- 1 beep = LOW
- 2 beeps = HIGH
To set this up, go to the Gadget tab and alter the Key Mode Setting for SA or SD from “Click on” to “Single”. This makes the momentary swap behave like a normal toggle swap.
You may as well remap the switches to channels you need.
Binding FPV Drones
Methodology 1: Utilizing Bind Phrase
As talked about, you should use bind phrase for binding. You possibly can set the bind phrase within the ExpressLRS WiFi UI (not the radio net configurator):
Methodology 2: Utilizing the Bind Button
The T8L has a devoted bind button, it places the radio in Bind mode. Then you too can put the receiver in bind mode by merely plug and unplug the battery 3 occasions.
Utilizing the T8L as a Simulator Controller
Utilizing the T8L for FPV simulators is plug and play for me.
Merely energy on the radio, join it to your PC with a USB-C cable, and launch your simulator (Liftoff, DRL, Velocidrone, and many others.). It’s instantly acknowledged as “Radiomaster SIM” with out requiring any drivers or setup.
For $35, it’s arguably the most effective price range FPV simulator radio out there at the moment.
Tear-Down
Let’s take a fast look contained in the T8L.
The radio makes use of a clear single-board design, nothing difficult and simple to take aside. Some controls, just like the gimbals and trim buttons, are linked utilizing plugs, making them simple to switch. Nonetheless, some switches are soldered on to the PCB, so changing these would require soldering.
You will have
- ESP8285 chip for ELRS Wi-Fi and Internet UI
- Semtech SX1281 for the two.4Ghz RF transceiver
- Ceramic antenna for the two.4GHz ELRS hyperlink
- Sq. wave wanting PCB antenna for WiFi.
There’s additionally an unlabelled connector below one of many battery slots. No official documentation but, so for now we don’t know what it’s for. Possibly extension for one thing cool sooner or later.
Radiomaster T8L vs. BetaFPV LiteRadio 4
These two radios are priced equally and share nearly an identical specs, so it’s inevitable to check them. After utilizing each, I believe the Radiomaster T8L comes out on high.
Why the T8L is Higher
- Superior construct high quality and design
- Extra intuitive configurator, and it’s web-based—no software program obtain required
- Higher inventory hall-effect gimbals
- Longer battery life thanks to 2 detachable 18650 cells
- Extra sturdy plastic shell
Whereas the LiteRadio 4 features a built-in 1S 2000mAh LiPo, the T8L’s twin 18650 cells supply dramatically higher battery life. You possibly can simply anticipate over 3 times the battery life with the T8L, and the flexibleness of swapping cells is a large benefit. However you do have to purchase the battery individually, so the T8L doesn’t actually have a value benefit.
The T8L is heavier (302g vs. 219g for the LiteRadio 4), however the further weight is sort of solely from the bigger battery capability. In use, the T8L nonetheless feels completely balanced and comfy for prolonged flying.
Points with Battery Voltage Detection and Low Battery Warning
Throughout my testing, I discovered the T8L’s battery voltage detection and warning to be considerably questionable:
- At 7.68V (3.84V per cell), the configurator stories 85%, and the radio exhibits 4 LEDs.
- At 7.50V (3.75V per cell), the configurator stories 76%, and the radio drops to a few LEDs.
- At 6.80V (3.40V per cell), the configurator stories 50%, and the exhibits 2 LEDs.
- At 6.2V (3.1V per cell), the configurator stories 30%, and the exhibits 1 LEDs.
- I didn’t get any audible low-voltage warning till the pack reached 5.5V, and the radio shut down nearly instantly afterward at 5.4V.
This behaviour suggests the voltage calibration could also be inaccurate, and the low-battery warning triggers far too late. As soon as the alarm beeps, you’ve nearly no time earlier than the radio powers off.
Sadly, I couldn’t discover any possibility within the configurator to calibrate the voltage studying or modify the warning threshold.
Hopefully Radiomaster can handle this in a future firmware replace. Till then, I like to recommend recharging the radio frequently slightly than counting on the built-in warning system—particularly for those who’re flying open air the place a sudden transmitter shutdown may very well be catastrophic. While you see 1 LED, it’s best to recharge the radio asap.
Remaining Ideas – Is the Radiomaster T8L Price It?
Total, the Radiomaster T8L is a improbable entry-level radio for anybody who desires to spend absolutely the minimal to get into FPV. It’s particularly interesting for inexperienced persons not sure about committing to the pastime, or for these wanting a reasonable controller primarily for FPV simulators or tiny whoops.
Get the Radiomaster T8L from:
If you happen to already personal a higher-end radio, the T8L is unlikely to switch it—it’s in all probability a downgrade in each vary and options. That stated, it makes a wonderful secondary transmitter, or a easy, budget-friendly radio for:
- Pilots who solely fly one mannequin
- Customers who hardly ever change radio settings
- Indoor or park-flying the place lengthy vary isn’t crucial
- Vacationers who need one thing light-weight and compact
For the value, it’s laborious to beat. The T8L delivers much more worth than you’d anticipate from a $35 radio, and regardless of its limitations, it succeeds at precisely what it was designed for.