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13 votes
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Can circularly and linearly polarized antennae be used together for FPV?

The compatibility of mixed polarity antennae depends greatly. For a little background in RF polarity, this diagram shows the difference between the four main types of antenna polarization available: (...
ifconfig's user avatar
  • 6,008
10 votes
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Can a receiver get damaged if you power it up without an antenna?

Running a receiver without an antenna should not cause any damage to the receiver, as no RF power is sent to the antenna (if your receiver has an active antenna there may be a DC bias present, but ...
Kralc's user avatar
  • 6,046
9 votes
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FrSky receiver snap-on connection problem

This type of connector is called a U.FL connector. Replacing the connectors will be super fiddly, but is possible if you are skilled with a soldering iron. The cable side is the more difficult bit ...
Kralc's user avatar
  • 6,046
8 votes

How to mount XM+ receiver antennas?

I really like the way the Joshua Bardwell does it. He puts one on each rear arm facing forward with a zip-tie and heat-shrink over the top. It places the antennas at 90 degrees to each other and so ...
Paul Kendall's user avatar
6 votes
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Can I mount my RX and VTX antennae next to one another?

The distance is dependent on the wavelength of the lowest frequency. You can calculate the wavelength $\lambda$ (m) from $\lambda = c \div f$, where $c$ is the speed of light in a vacuum (ms-1) and $f$...
Kralc's user avatar
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6 votes
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How to mount XM+ receiver antennas?

TL;DR: From purely a range consideration the 90 degree mounting is the best because of the orientations your quad might see. You'll want to get the antennas as far away from the frame as you can so ...
ipaq3115's user avatar
  • 525
6 votes
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Is it feasible to use an RC car transmitter/receiver to control an RC plane?

Maybe! Let's take a look at what parts from the RC car we might be able to reuse for an RC plane. You haven't shared any specific details about the RC car you're looking to salvage parts from or the ...
ifconfig's user avatar
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6 votes
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Brushless Upgrade for RC Car

The important points are: The physical size. One of these is labelled 'BL3650', which probably means that the can is 36mm diameter and 50mm long. Of course, it doesn't have to be exactly the same ...
Robin Bennett's user avatar
5 votes
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Taranis X9D Plus 2019: Switches SE,SF,SG,SH, and SI are not working/responding on Betaflight

The issue was on my Crossfire Nano receiver. I had to change the operation mode from 8 channel to 12 channel. Now switches from SE - SH work. Even though I defined all my knobs, switches, and button ...
DroneDome's user avatar
  • 567
5 votes

Can I mount my RX and VTX antennae next to one another?

The rule of thumb here is the further away from each other the better. The problem is, that receiver is operating on different band and so it has some input filtering to not receive "out-of-band&...
LQd's user avatar
  • 71
5 votes
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How do I test if my DX5e antenna is still good?

That's probably OK, but you should do a range test. All transmitters have a mode that transmits a much lower power than normal, and if that is sufficient to control the model at 30 paces, full power ...
Robin Bennett's user avatar
5 votes

Is it feasible to use an RC car transmitter/receiver to control an RC plane?

Back in the early days of RC, people only had single channel radios, and vintage models were designed to be flown with only the rudder (and a small amount of fuel in the tank to limit the maximum ...
Robin Bennett's user avatar
5 votes
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Binding DX5e (or any other hobby controller) to generic "toy" drone - protocol compatability

There are many different communication protocols used for radio controlled models and even for the same vendor the parts/versions are not always compatible. While most use the same chips to build ...
bingo-fuel's user avatar
5 votes

Could using a 2.4GHz controller frequency interfere with an onboard computer trying to access 2.4GHz WiFi networks?

The control radio will probably only interfere with the WiFi adapter when it's within a meter or two. Once the drone is flying the signal will be weaker and the error handling should be good enough to ...
Robin Bennett's user avatar
5 votes
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Can't disable SAFE or change SAFE mode

I found a solution the next day. I noticed that while holding down the panic button (A button on the transmitter, channel 6), I appeared to have full control of the controls. This led me to realise ...
ThatCoolCoder's user avatar
4 votes
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Possible to use Eachine E160 with Futaba T6EX transmitter/receiver set?

The product page of the helicopter states it is compatible with: FUTABA S-FHSS, expandable satellite receiver, and supports DSMX DSM2 PPM S-SUS Your TX/RX are from Futaba but from the older FASST ...
bingo-fuel's user avatar
4 votes
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r-xsr won't bind to qx7s

Okay, I solved it: I had installed the EU version of OpenTX, but I hadn't flashed the internal module on the transmitter. When I did that it worked flawlessly.
Hannes Hultergård's user avatar
4 votes
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Does the FS-R6B receiver work with the JJPRO EM-16 transmitter?

There are various digital protocols, and many receivers are able to handle more than one protocol (and so can a few transmitters). It looks like that transmitter uses "AFHDS 2A", so you need ...
Robin Bennett's user avatar
4 votes
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What is this 4th row of pins on some receivers?

Modern RC receivers that support PWM/servo output will also support other output modes, which is what the fourth row of pins are usually for. The extra row of pins you notice on the FlySky FS-iA6B ...
ifconfig's user avatar
  • 6,008
4 votes

Need tips on getting this to fly properly

That sounds like you don't have a flight controller. You won't be able to fly a quadcopter without electronic stabilisation of some sort. The basic configuration is not naturally stable. An analogy is ...
Robin Bennett's user avatar
4 votes

Could using a 2.4GHz controller frequency interfere with an onboard computer trying to access 2.4GHz WiFi networks?

No. Radio systems that claim to be "2.4 GHz" don't actually operate on EXACTLY 2.4 GHz. They have different channels a short distance apart. For example, nRF24 transmitters have an active ...
Proxy303's user avatar
  • 303
4 votes

Could using a 2.4GHz controller frequency interfere with an onboard computer trying to access 2.4GHz WiFi networks?

From a strict RF standpoint there will be some interference. This would occur if the RC and Wi-Fi were near the same frequencies, transmitting at the same time, some phase relationship and etc. The ...
Kevin's user avatar
  • 501
4 votes
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What is this pad on the HappyModel EP2 2.4G ExpressLRS Receiver?

The pad in question appears to be a continuation of the Ground pad, which when connected to the pad immediately 'above' (per the images) puts the receiver into 'boot' mode. See https://www.expresslrs....
Kralc's user avatar
  • 6,046
3 votes

Can circularly and linearly polarized antennae be used together for FPV?

To add to ifconfig's excellent summation of how the signal strength would be affected by mismatched polarizations, I must point out that in order to benefit from the reduction of multipath ...
FlashCactus's user avatar
  • 2,997
3 votes
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Difference between XM and XM+ receivers?

According to Oscar Liang, the XM+: Is larger and heavier than XM (21.5 x 12 x 3.5 mm – 1.6 g) Has diversity antennae, unlike XM Has solder pads in addition to pin headers Doesn't support Smart Port ...
ifconfig's user avatar
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3 votes
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Why don't multiprotocol transmitters work with Radiolink receivers?

The Jumper T16 multiprotocol module doesn't support Radiolink receivers, as you know. This is because the module doesn't have any hardware to recreate the Radiolink protocol. As can be seen on the ...
ifconfig's user avatar
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3 votes
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How to use an XM+ receiver without a flight controller?

Yes, you most certainly can. The device you will need is called an SBus Decoder, which splits the SBus serial signal from your FrSky XM+ into several different PWM channels. Example of an 8-channel ...
ifconfig's user avatar
  • 6,008
3 votes

r-xsr won't bind to qx7s

Another potential cause for not being able to bind is having a different radio firmware on the receiver vs the transmitter module. I recently ran into this issue with some of my setups. The RX was on ...
QuadMcFly's user avatar
  • 1,200
3 votes

Is it feasible to use an RC car transmitter/receiver to control an RC plane?

This is an interesting idea and I think it could work. There are, however, a few things that are worth considering. First of all, a controller for an rc car will usually have only 2 or 3 channels. ...
Jacob B's user avatar
  • 5,792
3 votes
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Working on a Quadcopter. Unsure if this flight controller supports an FS-IA6 receiver

So, I don't believe the components you have are entirely compatible with one another. The FS-iA6 RX only has PWM/PPM outputs, while the BetaFPV F4 AIO 1-2S FC requires some kind of serial RX. The &...
ifconfig's user avatar
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