PCB has no enclosure, the Cuav and pixhax mini for example have an enclose with pigtails coming off one end.
I’m not shy to solder, I do all the time and have nice bench Hakko equipment, I just don’t want open boards like that for what I’m planning.
I’m down between the Cuav Nora and Pixhawk4 Mini, but still reading and researching hoping someone can convince me of another unit similar in form factor
HolyBro Durandal. H7 processor vs. the F7 in the Mini. And better IMU isolation which probably doesn’t do much for you with a Plane. Not a recommendation just another FC in a case option. I suppose Cubes with a Mini Carrier Board would be another.
Hi Dave, the Durandal is a great recommendation, similar processor as Cuav nora but it is cheaper, you actually convinced me to look at this and not consider the mini anymore. I’m all about having more I/O for expansion and future capability.
Wise move IMO. New features and options are continually added so its prudent to spend a few $$ more now to protect for that.
Agree 100%, plus I’m just starting, last thing I want is to run out of I/O and be limited by the FC. Now just have to find a dealer that has it in stock. Seems like all the vendors are no longer carrying holybro products or went out of business
Banggood may be your only choice for a Durandal. I don’t know where you are but other Holybro FC’s are available from US retailers. But, these tend to be what’s supported by Betaflight also.
Thanks Dave i found it on there, since its coming from China i think i can order it directly through the MFG in that case.
I assume the same for this unit in terms of ESC powering the servo rail
and
Do you have recommendations on FPV/HD video cameras and communication frequency and reliable hardware?
runcam and caddx and foxeer have hybrid cameras and one that are self contained with its own battery.
Is there a reputable video comms link rx/tx like the Crossfire that you recommend?
I saw your question about this before. Crossfire is an RC protocol, nothing to do with video.
Beyond that no,
understand i was just referencing the Crossfire like dragon link as reputable RC protocol but looking for something similar for video.
I’ve been suggested ready made RC 1.3Ghz for video but that is about it
Can i get some feedback on radio links.
RC should be the lowest frequency
Video higher than RC
How about the Flight Controller Telemetry? Can that be the same frequency as the RC or will this cause problems?
Lets assume one uses Dragonlink or Crossfire at 900Mhz, than 1.3Ghz for FPV, the FC telemetry option being 900MHz is that okay?
How about if the FC telemetry is 433Mhz and its lower?
Wiki doesn’t quit tell you much other than what is available: https://ardupilot.org/plane/docs/common-telemetry-landingpage.html#common-telemetry-landingpage
If you’re using dragon link you can have full telemetry and RC link on the one unit. You would only need to add a VTX. Another option is the RFD900X system. It will also do RC and telemetry on one link. (Crossfire says it also can, but no, it can’t. Not yet at least)
Technically the 400MHz (433) will go further than the 900MHz (915), but for most consumer grade gear I don’t think the difference will be too much. The other thing to consider is that 400MHz gear is typically for Europe, and 900MHz is North America and Australia. Depending on where you are you may run into interference (or cause interference) if you use the wrong one. And then again, if you’re in the middle of no-where it probably doesn’t matter.
I’ve never seen telemetry radios below 400MHz (but now that I’ve said that someone will provide an example 
) As you get lower in frequency you’ll get better range, but you will have lower bandwidth so less/slower data.
Hi Allister, thanks for the great feedback.
On the crossfire subject, I’ve checked the wiring diagrams but I didn’t see anything in Crossfire that allows the Rx to connect to the Telemetry port on a Pixhawk for example? Some do have a port but I don’t believe the pigtail is standard you see on Pixhawk, I don’t know if that is reserved for their own telemetry products but lets say it is not. On the TX side (Standard model) there is no USB connection like you see with the FC telemetry TX/RX made specifically for these flight controllers to be able to connect to a PC or Android tablet for Mission planning? How would you send that data from the crossfire Standard TX to a laptop or android device? (Is this why you say it can’t be done?)
(https://www.team-blacksheep.com/tbs-crossfire-manual.pdf)
I guess my follow up question is if the Crossfire is 900Mhz and the FC telemetry is also 900Mhz(assuming the crossfire does not connect to laptop as I described above) is this not a good setup as the FC Telemetry being on the RC link both at 900Mhz could cause issue and problems?
thanks
I don’t know about Crossfire but I have 915Mhz RC and 915Mhz telemetry radios on some craft w/o interference. I suppose it depends on the type of protocol used.
In most cases for me the 915Mhz telemetry is redundant as I get what I need on the Transmitter. FPV users with OSD say the same thing.
Thanks for the feedback Dave, at least if worse comes to worse that is what I will have to run.
Now i’m debating between Crossfire and Dragonlink. Any thoughts?
No skin in that game I use Frsky 915Mhz. If I had no hardware I suppose I would either go with Crossfire or maybe ExpressLRS. I may Transition my Frsky stuff to ExpressLRS at some point anyway when support for Frsky telemetry has matured a bit
Thanks, i’m going to research ExpressLRS now
I suppose it depends on the source of info but this seems to me to be in a Beta stage still. And transitioning all my Frsky stuff over would be a huge PITA so I’m waiting…
Makes sense, the info they posted about latency and frequency delta is quite enticing if they have a stable version. I’m leaning towards dragon link now, have to keep reading.
Crossfire, Dragonlink and RFD900 will all connect to the pixhawk the same way, through an open serial port.
Crossfire is more about low latency. It’s a solid, fast link, but unless you’re shooting tight gaps, that may go unnoticed for most long range flying.
Dragonlink has much better telemetry performance compared to Crossfire. Through Dragonlink you can have both RC control to your radio and Mavlink telemetry to your GCS. Because it’s one link, you don’t have to worry about interference issues between RC and Telemetry. The Dragonlink module will be on your radio and has a WiFi module that you can connect your GCS. I’ve only setup one plane with Dragonlink. It worked, but I wasn’t a fan of the physical gear. I didn’t like how the TX module mounted to my radio, and I didn’t like the antennas on the RX. The one I used was an older module so I had to do a DIY mod to upgrade from the bluetooth to wifi GCS link. It worked, and once I got everything set up it was stable, but it wasn’t my favourite. I switched to RDF900X TXModV2. The basic concept is the same (RC link and wifi GCS), but the physical setup of RDF900 was more appealing to my projects. Both Dragonlink and RDF will support Yaapu telemetry on your OpenTX radio as well.
Crossfire is trying to do the same, but if it’s just not mature enough yet in this space. You can use two serial ports, one for CRSF and one for MAVLink (if you’re on 4.1). With the MicroTXv2 I’ve been able to get wifi GCS link using this configuration. It works, but the MAVLink GCS is unstable. When CRSF support becomes stable in 4.1 I may switch a few more of my personal projects to CRSF in hopes that the GCS link improves. But this is mostly a financial decision. The CRSF system came out of my own pocket, but the DragonLink and RDF systems belong to my employer. And the CRSF Nano RX is a fraction the size of the others. All that said, if GCS telemetry is a priority for your project, I wouldn’t recommend it.
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