Quanum FPV Diversity Receiver – RC540R 5.8GHz 40CH

Diversity video receiver is becoming popular for FPV, and Quanum recently released their first diversity receiver for 5.8Ghz which we tested this week.

Get your Quanum RC540R FPV Diversity Receiver from Hobbyking.

This is a very simple unit, there is only one single multi-directional button that makes it very easy to use. There are 2 AV outputs and it takes 12V DC input. The antenna connectors are SMA.

Quanum FPV Diversity Receiver package content unbox

Quanum FPV Diversity Receiver video connectors 1 2 power plug

Awesome Features

It’s not just a diversity receiver that supports Raceband, it also comes with 2 other great features:

Independent mode – A diversity receiver is basically 2 receivers built together, which means it is possible to tune into 2 different channels at the same time. It’s useful when you want to see 2 different racers on 2 separate screens, or hook up your DVR’s to record their footage, at the same time with only 1 receiver device.

Spectrum Analyser – It actively sweeps the whole 5.8Ghz frequency band, and indicates what channels are transmitting signal. It’s great if you are going to a meetup or race, before you power on you can check what channels are free/safe to use. This is done with one antenna/receiver, which means you can still use the other antenna/receiver for video output.

Here are some screenshots of the screen in operation. Notice the purple/blue LEDs on the top, these are indicators showing which antenna/receiver is being used for video output (purple).

Quanum FPV Diversity Receiver screen led menu

Field Test

Just a quick test on the diversity receiver on my Fatshark Dominator V2 goggles, comparing the result with the old Fatshark Receiver (which has only 1 antenna).

I only tested the Quanum Diversity unit with 2 cloverleaf antenna’s (that are tuned to different frequency). I should have replaced one of the antenna with some higher gain ones, like a helical or patch antenna to get the most out of it, but didn’t have any with me.

It’s pretty easy to hook up the Quanum diversity receiver with the DomV2 goggles. The goggles allows you to turn off the internal video receiver, and connect to an external one via the AV port. I only use video so I left the 2 audio cable unconnected.

Quanum FPV Diversity Receiver with fatshark dominator V2 goggles

In the test I picked a couple of spots that are behind many trees, with the Fatshark receiver I normally got very weak signal, sometimes even lost signal completely.

Quanum FPV Diversity Receiver testing fatshark rx with single antenna Quanum FPV Diversity Receiver testing fatshark rx with single antenna 2

It’s pretty clear that the diversity receiver worked a lot better, when flying at those same spots it still picked up the signal, and the video was still visible and flyable.

Quanum FPV Diversity Receiver testing 1 Quanum FPV Diversity Receiver testing 2

Here is a video of the test.

Here are the manual/instructions for our reference.

Quanum FPV Diversity Receiver manual 1 Quanum FPV Diversity Receiver manual 2 Quanum FPV Diversity Receiver manual 3 Quanum FPV Diversity Receiver manual 4

Secret hidden menu

The following instruction allows you to access the service menu option of the Quanum 5.8 Diversity Receiver, to change default settings such as RSSI strength and switching times.

How to enter the service menu

While pressing and holding down the “Enter” button, while powering the receiver ON, the receiver will enter service menu.

test mode-quanum rc-540r diversity fpv video receiver

Here we will explain what each option (test) does.

1. “Setup Div level”

RSSI LED level – level of RSSI when Blue LED will turn ON (with presence of video signal
of course). The number is in RSSI percentage.

DIVERSITY_LVL – difference in the levels of two RSSI’s when the decision of switching will
be made. It is the RSSI hysteresis value. The value is set in RSSI percentage.

The less the number is, the less RSSI difference is required to initiate antenna switching. Setting very low hysteresis value will cause false switching.

DIVERSITY_TIME – approximately 100ms per point, depends on the many factors, max
is 150ms. Reducing this number will cause switching earlier but as a trade-off -premature
switching or erratic switching back and forth in WiFi dense areas.

General rules of settings and recommendations: Timing of switching depends mostly on

  1. How long RSSI1 is higher than RSSI2 consequently (DIVERSITY_TIME)
  2. Threshold between RSSI1 and RSSI2 in percentage when timer starts counting
    time (DIVERSITY_LVL). If threshold is low the timer starts earlier and switching occurs
    more often. If threshold is high then there should be more significant difference between
    RSSI 1 and 2 to make it switch. The algorithm also analyses the RSSI to estimate
    environment quality – noisy urban or clean rural areas and it affects timings a bit.

Trying different values for these settings to find an effective for your setup.

2. “Screen test”

RIGHT button will change screens.

screen test-quanum rc-540r diversity fpv video receiver

Press ENTER to exit to main menu

3. “Speaker test”

Pressing RIGHT button will turn speaker ON, pressing LEFT button will turn speaker OFF.

speaker test-quanum rc-540r diversity fpv video receiver

Press ENTER to exit to main menu

4. “LED Test”

led test-quanum rc-540r diversity fpv video receiver

 

  1. Press NAVI button UP. Right blue LED will be ON
  2. Press NAVI button UP one more time. Right blue LED will be OFF
  3. Press NAVI button DOWN. Left blue LED will be ON
  4. Press NAVI button DOWN one more time. Left blue LED will be OFF
  5. Press NAVI button RIGHT. Left red LED will be ON
  6. Press NAVI button RIGHT one more time. Left red LED will be OFF
  7. Press NAVI button LEFT. Right red LED will be ON
  8. Press NAVI button LEFT one more time. Right red LED will be OFF
  9. ENTER to exit to main menu

5. “Menu Rx Test”

a) Press RIGHT to change channel on Rx1 and select channel of your video transmitter
RSSI number will become large and letter “V” appears

menu rx test-quanum rc-540r diversity fpv video receiver

b) Select Rx2 and select channel of your video transmitter
RSSI number will become large and letter “V” appears

c) Press ENTER to exit to main menu

6. “menu Switch Test”

menu switch test-quanum rc-540r diversity fpv video receiver

Pressing left and right buttons allows manually assign outputs to any of two antennas in
any combination:

  • Both outputs out to left antenna
  • Both outputs out to right antenna
  • Left output to left antenna and right output to right antenna
  • Left output to right antenna and right output to left antenna

Troubleshooting

Problem Solution
1 Receiver finds channels during scanning, Blue LED is ON on active channel but no video on the monitor or goggles Check AV cable and monitor settings/Input selection
2 Receiver cannot find channels or picture quality is poor Check antenna/ antenna connector/transmitter
3 Receiver finds active channel and the picture is mixed with another
picture
Another transmitter works at the same channel.
Coordinate channels with your fellow flyers.
4 Device stopped working or doesn’t work as described (display turned off or characters are corrupted, no video out, no control etc.) Recycle the power.

9 thoughts on “Quanum FPV Diversity Receiver – RC540R 5.8GHz 40CH

  1. helicocrasher

    The channel naming seems to be “special”.
    The F band is displayed/called A,
    the A band is displayed/called B
    the E band is displayed/called D
    and the race band is disaplayed/called R
    Seems confusing to me.

    Reply
  2. Lloyd

    You can change the diversity timer to switch between the 2 antennas, by default it is 10 second, which is way too long

    Reply
  3. BWX

    I would have liked to see how many times the Quanum diversity switched during that video. My guess is zero times from what I have seen so far. It doesn’t change fast enough at all. From what I have seen it is basically like running a diversity with a huge delay which is like running a single receiver unfortunately.

    Reply
  4. ozzymuppet

    RE: Cloverleafs tuned to different frequency. I assume this is as they’re different brands, given the slight differences its likely the tuning will be different yes?

    Also, do you have any special pick for non megabucks antennas? I like the AOMWAYs myself.

    Reply
    1. Oscar Post author

      The antenna in the picture without any casing is tuned to ch7 on IMRC band, it’s custom made :)
      i quite like the spironet, with some fibre tape it’s nearly indestructible so never have to replace them LOL. I haven’t tried the aomway yet

      Reply

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