In this post I’ll be reviewing the new Eachine TX250 250mW video transmitter from Banggood. Here are the specifications:
- Transmitting Power: 250mw
- Operating voltage: 7V-26V
- Channels: 40 (Raceband capable)
- Dimensions: 21X32.5X8.1 mm
- Weight: 7.5g
- Connector: RP-SMA
- Antenna Circular Polarization: RHCP
Here is a frequency chart:
The included manual:
My first impressions of this VTx were very good. It comes packaged quite well in a cardboard box with foam padding, compared to the plain anti-static bags I am used to receiving products in. The VTx itself is only slightly larger and a couple of grams heavier than the extremely popular Aomway 200 mW VTx. However, the added size could make a difference in micro builds.
This VTx uses a push button for changing channels instead of the typical DIP switches (like that on the original Aomway). This makes it much easier to switch channels, but it also increases the risk of stepping on someone else’s channel if you fly with others. This is because you must cycle through many frequencies while the transmitter is powered on, meaning that may pass over a frequency someone else is using. With the Aomway you can power off, go directly to the frequency you have been assigned, and power on. Using an RF terminator/ dummy load could reduce the risk on the TX250.
The antenna seems pretty durable. Initially it was easier to bend, but held its shape better than the blue Aomway antennas. However, now it tends to start drooping a bit, and the thin spot on the antenna looks like it could be a point of failure. Inside the case, this is a 3-lobe RHCP cloverleaf. This seems like a generic cheap cloverleaf, so I am not expecting the greatest performance out of it. I may replace the RP-SMA connector with an SMA one and use some other antenna on this quad instead.
Installation/ Flight Testing
I installed this VTx on my large Reptile 500 quad (which was also my first quadcopter) but did not get to test it for a while due to heavy rains. I came across a bit of trouble while setting it up as the camera I was using (Eachine CCD 1000TVL) is 5V input whereas the red wire of the servo plug that comes with this VTx is direct battery voltage (Vcc). I incorrectly assumed it is regulated 5V like the Aomway 200mW and plugged it directly into the camera. To be fair, the manual does mention this, but it would be nice to have this labelled on the VTx as well. The camera heated up a lot and the video was full of interference. Luckily, I noticed my mistake in time and the camera survived. I moved the red wire to the 4th pin in the connector on the VTx side by lifting the tab in the JST-SH with a hobby blade and sliding it into the other slot. This is the one next to the white wire on the other side and is regulated 5V. This is also mentioned in the manual but again, labelling on the VTx would be nice. For those who want to use audio with the VTx, the manual claims it is supported (the 5th pin) but there is no cable for it. You will need either fine soldering skills, pre-crimped JST-SH wires or a crimping tool if you want to use it.
Range on this transmitter is pretty good. I use an FR632 diversity receiver with an Aomway helical antenna and Aomway cloverleaf and I flew out to a couple of hundred meters with solid signal. I did not try flying behind any obstructions though. This being the first time I was flying FPV on this quad and this location, I played it safe and flew relatively close by. Since this quad is equipped with GPS and is capable of RTL, I will try flying to the limits of this VTx and update this review soon.
After using this VTx, I would say its pros and cons are as following.
- Single push button for frequency changing and frequency display: This is definitely more convenient than fiddling with tiny DIP switches.
- Included cloverleaf antenna: You don’t get another of those whip antennas that end up in the junk box anyway.
- Simple to use: This was practically plug and play with the Eachine 1000TVL camera. The cables are nice and short and do not require cutting and soldering like the Aomway cables.
- Solid range: I haven’t got to test this to its limits yet but so far it does appear to have pretty good range, sufficient for most mini quads.
- Push button for frequency changing: Although I mentioned this as an advantage of this VTx, it is also a disadvantage in some ways as it increasing the risk of stepping on someone else’s frequency while changing channels. As long as you are extra-careful with frequency management while flying with others and/ or use an RF terminator, this is not a deal breaker.
- Included antenna: The stem of this antenna seems like it could wear out with multiple crashes. The quad I put this VTx on is not as crashable as minis so I won’t be able to test it for myself. However, considering that this VTx including a CP antenna costs less than the Aomway VTx alone, it is a pretty good deal even if you have to replace the antenna eventually.
- Cable pinouts: One thing to watch out for is that the red wire to the camera is full Vcc. As long as you are aware of this, it is not a big deal and can easily be switched to 5V. If you want to use audio, the included cable does not have a wire for it, but I am not sure how many pilots fly with a mic anyway.
Overall, this is a pretty good VTx for the price. It is especially convenient for those new to FPV but works well even for experienced pilots. The push button simplifies channel switching and the included cloverleaf is a nice touch. I am definitely happy with it so far.
You can buy this VTx from Banggood.