FPV system

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I use a first person view (FPV) system (camera, transmitter, receiver and display) both under my drone, as well as in a LEGO train (allowing you to get a driver seat view).

Runcam 2 system

The first first person view (FPV) system I used was a Runcam 2 system.

Manufacturer website: https://shop.runcam.com/runcam2/

Despite it's build in battery, it was fairly small (21mm high, 38mm wide, 66mm deep), so fitted in the LEGO train (most action cameras are too high or too wide).

The disadvantage was that the runcam behaves as a wifi basestation, to which you connect the iPad or iPhone. This was not a stable connection. In addition, it interfered with the control of the drone, also at 2.5 GHz. Since I wanted to always be able to control my drone, I turned wifi off, and only made recordings on the included flash card. The second disadvantage was that I was frequently unable to turn the camera on: pressing the on button simply did not turn it on. I bought a second battery, but the problem persisted. After about a year with various results, I gave up using the Runcam 2.

Resolution: 1920*1440

Standard password for the "runcam"

5.8 GHz system

Instead of wifi, I later bought a camera and receiver based on 5.8 GHz transmission. This system simply transmits analog video streams, and is frequently use for racing drones. That advantage is there there is virtually no delay between the time of recording and the display on screen. In addition, when the connection becomes too weak, you will get more noise, but the video feed may still be eligible. This is unlike a wifi connection which has longer latency and drops the connection completely if there is too much noise.

Hawkeye Firefly Fortress Micro FPV Camera

The Hawkeye Micro FPV Camera is an all-in-one system, with combined camera and 5.8GHz transmitter.

Manufacturer website: http://www.cnfpv.com/portal.php?mod=view&aid=104

The modules can be separated (with 10cm wires in between), which allows better positioning in a drone or vehicle.

It allows for a wide range of input power. According to the specs 1S (3.7V), 2S, 3S up to 6S (22 V). In my experience, when connected to a single (1S) LiPo battery, the LEDs light up, but I don't get an image on the receiver. When powered with 2S, all works fine. I had good experience powering it from a LEGO Brick (with 6 NiMH batteries) that was drained to 6.5 Volt total, and the camera still worked fine. Note that the transmitter can only take 3.3-5.5V, but this is properly capped by the camera, which is connected to the battery.

The camera settings can be adjust with a small 5-button touch pad that can be connected to the camera. The settings are displayed as an on-screen display.

The transmitter settings can be adjust with a small button on the main board. a short press cycles through channels (1-8), a 2-second press cycled through the bands (A-F (and H?)), a 5-second press cycles through transmission power.

Available transmission power are: low ("0" mW), for very short distance testing, all LEDs off; 25 mW (1st LED on); 50 mW (2nd LED on); 200 mW (3rd LED on).

Camera resolution is 960 lines.

Receiver

The receiver is an unbranded "5.8G FPV UAV video wireless transmission". It features a 4.3 inch screen, and build-in LiPo battery (600 mA, 3.7 Volt)

5.8 GHz frequencies

Both the Hawkeye and FPV receiver use their own intricate description to select one of the 48 or 40 channels. This table assumes the out-of-the-box frequencies for the Hawkeye transmitter. It is possible to remove a resistor to allow 72-channels, starting with (more common?) 5865 MHz for A1.

VTX Name Frequency Hawkeye designation Monitor designation Possible Interference
Boscam A 1 5865 MHz C8 CH11
Boscam A 2 5845 MHz C7 CH12
Boscam A 3 5825 MHz C6 CH13 wifi channel 165
Boscam A 4 5805 MHz C5 CH14 wifi channel 161
Boscam A 5 5785 MHz C4 CH15 wifi channel 157
Boscam A 6 5765 MHz C3 CH16 wifi channel 153
Boscam A 7 5745 MHz C2 CH17 wifi channel 149
Boscam A 8 5725 MHz C1 CH18 wifi channel 144
Boscam B 1 5733 MHz D1 CH21 (wifi channel 148 is unused)
Boscam B 2 5752 MHz D2 CH22 wifi channel 149
Boscam B 3 5771 MHz D3 CH23 wifi channel 153
Boscam B 4 5790 MHz D4 CH24 wifi channel 157
Boscam B 5 5809 MHz D5 CH25 wifi channel 161
Boscam B 6 5828 MHz D6 CH26 wifi channel 165
Boscam B 7 5847 MHz D7 CH27
Boscam B 8 5866 MHz D8 CH28
Boscam E 1 5705 MHz A4 CH31 wifi channel 140
Boscam E 2 5685 MHz A3 CH32 wifi channel 136
Boscam E 3 5665 MHz A2 CH33 wifi channel 132
Boscam E 4 5645 MHz A1 CH34 wifi channel 128, weather radar
Boscam E 5 5885 MHz A5 CH35
Boscam E 6 5905 MHz A6 CH36
Boscam E 7 5925 MHz A7 CH37
Boscam E 8 5945 MHz A8 CH38
Fatshark F 1 5740 MHz B1 CH41 wifi channel 149
Fatshark F 2 5760 MHz B2 CH42 wifi channel 153
Fatshark F 3 5780 MHz B3 CH43 wifi channel 157
Fatshark F 4 5800 MHz B4 CH44 wifi channel 161
Fatshark F 5 5820 MHz B5 CH45 wifi channel 165
Fatshark F 6 5840 MHz B6 CH46
Fatshark F 7 5860 MHz B7 CH47
Fatshark F 8 5880 MHz B8 CH48
Raceband R 1 5658 MHz E1 CH51 wifi channel 132
Raceband R 2 5695 MHz E2 CH52 wifi channel 140
Raceband R 3 5732 MHz E3 CH53 (wifi channel 148 is unused)
Raceband R 4 5769 MHz E4 CH54 wifi channel 153
Raceband R 5 5806 MHz E5 CH55 wifi channel 161
Raceband R 6 5843 MHz E6 CH56
Raceband R 7 5880 MHz E7 CH57
Raceband R 8 5917 MHz E8 CH58
Diatone D 1 5362 MHz F1 Atmospheric research
Diatone D 2 5399 MHz F2 Atmospheric research
Diatone D 3 5436 MHz F3 Atmospheric research
Diatone D 4 5473 MHz F4
Diatone D 5 5510 MHz F5 wifi channel 104
Diatone D 6 5547 MHz F6 wifi channel 108
Diatone D 7 5584 MHz F7 wifi channel 116
Diatone D 8 5621 MHz F8 wifi channel 124, weather radar

Beware of technical and legal limitations:

  • Only frequencies between 5470 and 5925 MHz are allowed in Europe, so some of the D and E band may not be used! These are marked in red. In the US, the same limitations seem to apply.
  • The maximum power for a transmitter is 25 mW, which is not very much. This formally applies to non-specific short range distance (SRD) equipment, for e.g. telemetry and alarming, operating in the 5725 – 5875 MHz range.
  • For wifi equipment, operating in the 5470 – 5725 MHz range, the transmit power may be as high as 1000 mWatt, although with further limitations: max 50 mW/MHz, and compulsory use of transmission power control (TPC). Note that this is significantly higher than the max of 100 mWatt for 2.4 GHz wifi.
  • Reports on the Internet noted that for clear line of sight, you can get up to 750m on 25 mW, but that is easily reduced to 200m with trees, or 50m indoors. 200 mW power would roughly double that distance. Some people reported flying with 600 mWatt, but stipulated that was in remote locations only, with no risk of interference because 5.8GHz signal are easily dampened over distance.
  • Like wifi, a major source of signal block comes from water. E.g. foliage outside, moist in the air, indoor pipes, or those large moving sacks of water called humans.
  • Wifi5 (802.11n) and Wifi6 (802.11ac) only use channels 36-64 and 100-144.
  • The weather radar may also be a source of interference. The FCC had reserved 5600 - 5650 MHz for "meteorological aids", and the Dutch Doppler radar also operates in the C-band (5.6 GHz).

Legal pointers: