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  1. IBV

    IBV

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    Hi there,

    Now finally I got all set up... and already run into a problem which I have no explaination for..:

    I got:
    2 120cm long 12dbi TP-link omni-antennas on the roof.
    2 Sunhans golden 3W boosters
    2 10m long RP-SMA antenna cables from the confernece room to the roof.

    I tested the big antennas with a short cable and they work excellent. Both Sunhans boosters show a permanent blue light (and not blinking like written in the manual but this seems normal)
    I tested the big antennas from the roof and suddenly the left Sunhans amp is only displaying white light (no signal).
    I thought this gonna be an easy troubleshooting and changed the antenna cable (and thus antenna) from left to right.- same problem! Still the left amp shows white light.
    I then changed the amps as well to see if the amp got a problem but then again the left side only showed white light. My conclusion is that the amps actually work. I then connected the outputs of the amps to my dbs02 antenna and both work again.
    Today I went up the roof with the RC and connected the roof antennas with short cables and both amps show blue light,
    I also tested to fly with the white light on and it works. However, it doesn't seem to amplify anything but also doesn't block the signal through the amp.
    It obviously has something to do with the long cables but I'm confused as I cannot say what the problem is nor which cable (I twisted them).

    Does anybody of you know why only left side shows white light with long cables? What does the left side do? - I unplugged the amplifier shortly and saw the video link went off.
    Can it be that the cable is dampening the receiving signal so that the amp lets it through but it's just not enough to trigger the blue LED on the amp?
    What cable specs should I use for long cables?
    I know Jermeiha got some experience with his "flying frominside the house".


    It would be great if you could help out...
     
  2. Mark The Droner

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    This kind of problem is discussed in this thread and the recommended cable seems to be in this post:

    Sex, Lies and Roof Top Antennas!

    But even then it's going to be challenging. And expensive.

    Re the blue lights, I'm not exactly sure what the deal is. I have two silver Sunhans. One blinks blue, the other is solid blue. I'm not quite sure why one is solid. Seems to me it should blink.

    There is at least one more thread somewhere discussing rooftop antennas and cables.

    Hope this helps somewhat.
     
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  3. flyboy73

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    There is considerable loss in cables at the frequencies you are dealing with. It is likely that unless your cable is very low loss, and designed for those frequencies, you are getting almost no RF energy to the antennas at all, and your receiving signal is also being attenuated to a very large degree. What type of cable are you using? For lengths you are talking about I wouldn't expect much unless your cable is of the type used by for satellite reception. It would probably be double shielded and about one inch in diameter.
     
  4. Sim597

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    Without reading your whole post, I've got same thing, lol Except backwards my downlink amp, or the right one doesn't glow the blue lights, I think we have somehow blown the amp for that channel, or it's not enough to kick it in. Mine is only receiving on the left side so I took the amp out of the equation and just flew past my battery, just barely made it home, now my FC signal was pegged the whole time, but as usual my DL was spotty past 2 miles but was full bars when I turned around at 3.1 miles


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  5. Sim597

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    I think he's using LMR-400 which is what I use and others, you lose about 3.4dB in 50' plus another dB in the "whips" which he should use of LMR-400


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  6. Sim597

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    It is blinking, but your remote is working properly, it's just so fast, and both ways possibly for flight control and telemetry date coming back, in test one side send/receives, the other, the left just receives


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  7. Sim597

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    Oh, I see in the post, the other commenter is correct, you can't use any old cables that are 30' your loss is tremendous. Even without a booster if u use 30' of LMR-400 you will get a signal


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  8. IBV

    IBV

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    Thanks for all the answers. I don't know which cable I'm using. It says 50ohms h155. Thought of changing to
    One with 0,46db loss per meter (ca3 feet) and using 2 pieces 4Watt Sunhans boosters on the roof.
    What is the left side of antennas actually doing? Is it the downlink?
     
  9. IBV

    IBV

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    OK. That makes sense
     
  10. IBV

    IBV

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    I will try to place the left side amp on the roof and right side near the remote..... If left side is downlink only and right side is Rc bi directional. Can anybody confirm that this is the case?
     
  11. Sim597

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    There was a guy that actually tested this, maybe it was either Gadgetguy or Jussaguy I think. Im positive the left side is Flight control and right side is HD downlink. I can also say for sure the right side does no transmission. I don't remember exactly but I think I remember that the left side, which makes sense, has the "room" to return the data back to the ground station, while controlling the AC. The HD channel doesn't have much more bandwidth due to video, but flight control doesn't take a bunch of actual bandwidth, just fast data, so the tiny bit of telemetry data is received in the left side along with control, right side is just for video


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  12. Sim597

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    Yes, but that above. I see you've got the 4w they're Awesome, don't get me wrong, but even with the inspire remote, ppl are saying they won't "catch" the signals from the remote for some reason, not strong enough? I don't suggest running amps in tandem, there is plenty of Info about why this doesn't work, even Jeremiah who said he got a little benefit off this crazy setup, no longer uses it, or recommends it. That's up to you, either way, good luck bro.
    I will say this, make sure your A game is on when your not there to see to land. I've gotten pretty good but still because of tall trees, I've got to thread a needle to bring mine in, and the wind, you won't feel it change, or see it, it's just a different deal, I liken it to Instrument flying, because it is, but without the benefit of feeling the Gs and motion you have in real flight at least.
    Nothing like sitting in the AC flying 3+ miles away. I've run my battery down pretty low, and when inside three times its started to land while I'm landing, so that's another thing, I hate coming in at 11% because I really have to fly to bring it to my porch, takes over a minute to bring mine in last 30' after bringing it thru trees.
    Here's another thing I learned. Apps that don't let me use the radar, both ways, the vision for actual altitude (above house roofline and when landing) and the radar on screen are great helpers in instrument landings. A P3P or a TyphoonH or an inspire are all left behind on this one thing. The TyphoonH has the radar, but the 5.8 freq. is too tall to put into a 50' cable, you'd have terrible loss.
    So the P4 using the P position is the only way I will bring my bird in when I cannot see it, the radar is a HUGE bonus. The vision system working at 30' and not 10' is also invaluable.
    Good flying bro, good luck with the test. If you haven't gotten the LMR-400 cable, I got a great deal on eBay for two 50' runs, no shipping with the connections on it, $100 total, free shipping. It's Wilson not Times Microwave, but it's not Chinese crap, it's as good (arguably) as TM


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  13. Sim597

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    LMR-400 cable has loss of 6.8dB per 100' you can buy LMR-600 cable, that's like 4.2dB (I'm guessing as I Dont remember exactly) but I remember in my 50' lengths, the cost vs saving less then 2dB isn't worth it. The 400 is 3/8" and the 600 is 1/2" thick! So it's some heavy duty but you don't need all that, especially if doing 30' runs, get Wilson or Times Microwave LMR-400 and you'll be golden with like 2dB loss


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  14. Sim597

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    We're talking like 45dB on my FC side. I'm not using amps on my HD channel side, so I'm at like 19dB on that side. The FC channel is super strong and barely ever moves off of 5/5 bars, even at range, so already way over FCC regs


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  15. IBV

    IBV

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    Just to complete this thread. It has been further discussed under the "flying from inside the house,etc.." thread.
    After testing several options and with two 3W and rwo 4W boosters near the roof antenna the conclusion is:

    The 15m coax cable dampened the signal so that the Sunhans golden 3W booster on the HD downlink side never triggered the blue LED to blink.
    With the 4W boosters at antenna side it seems to be sufficient to drive the cable and both blue lights are now there!. The booster near to the RC (downlink side) is not need actually. It also seems that when flying close the P4 or the RC is distorting due to too much of gain at the input of the P4 side or RCside internal amps. This is a minor issue. Range and penetration increased. Didnt test long range fully yet.
     
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  16. Sim597

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    I had one amp go bad on the power pin input, so I go to use the other one, and Signal drops at 800' or so, so I had one great amp that worked excellently, and the other it seems even with the blue light working, something else is going on there. I don't have the heart to tell Jake, but if he'd let me return the one that isn't easily seen to be broke (the one doesn't even power up) I'd send him some money just for the trouble, hate to even ask the guy, but right now, i have no working amps. I bought a cheap black 4W for like $21 on eBay, but I like those gold Sunhans, would love to see what I can do with two that are working correctly.
    It seems one of my problems was this amp they lights up, but clearly doesn't work, I've put 800,000' on the bird with the antenna on the roof, I know what and how far I can go, this second amp is certainly not working correctly, crap
     
  17. IBV

    IBV

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    That sounds bad. The specs of the Golden and the silver amps look same apart of the Silver one being 4W and the Led shows up and downlink. The golden are minimized for having them on the RC. But that comes at the cost of more difficult heat handling when boosting strongely. both got automatic gain control. the 4W on the roof work perfectly. When going behind obstacles the penetration is excellent. I tested the 3W and it seems the 4W are having a steeper amplification curve. both are none linear but the 4W seems to handle weaker signals better.
    Good luck with the change of the amp. Power pins are often the weak point in hardware these days. Wonder when they finally get this sorted.