Lost signal, lost plane

Hey there,
I've been flying my ultra micro sbach 342 and umx Pitts special using my Devo 8s for a long time without any problem. But I've had two catastrophic crashes in the last 2 weeks both from a signal loss. But here's the thing, when I fly them in a field I can take them out right to the edge of sight, Easily 100 yards or more. But the two crashes I experienced occurred while flying on the roof of my apartment's sixth floor parking garage And at a fraction of the distant I routinely operate them. The first crash happened to my UMX sbach. I took it up and had no problems through the first two batteries. I would fly past the edges of the parking garage with no issues. But on the third battery after about 2 minutes of flight I had the plane heading away from me, about 25' over my head and maybe 55' Out from me, and no more than 20' past the edge of the garage roof and it just lost signal and fell out of the sky. I had never had a problem with signal before so I started going over other possible issues. I found the plane shredded but all the internals were in good working order except the battery which I was unable to find. I just didn't want to believe it was a signal issue because of the extensive range I've seen in the field and since I made the rookie mistake of forgetting to check that batteries voltage before flying I was leaning towards a bad battery.
So yesterday I was again flying from the parking garage roof, this time with the UMX Pitts special. I made sure to double check the battery and had a great first flight. I kept the plane in a tighter vicinity, to ease the worries in the back of my mind that I could have experienced signal loss. I then checked my second battery, and put it up again. I flew problem free for about 3 minutes and while turning it back towards me, literally no more than 40 feet out and 15 feet up when it lost signal. HEARTBREAK. Just like the first crash I was past the edge of the parking garage roof. But I had made that same pass at least 15 times between the two batteries without issue, and this time I'm positive the batteries voltage was good before flight.
The UMX pitts wasn't as lucky as the sbach, it is lodged in a tree about 4 stories up, and I ran out day light trying to rescue it.
So the main question I've been trying to get to is what kind of effect on signal would flying from the top of a 6th floor structure create? please forgive for rambling, but im sure most of you can relate to the grey cloud that comes over you when you lose a model.
Also does anyone have any suggestions to help optimize signal? Tips? Products? I recently purchased some fpv equipment and Before I start hanging planes with cameras up in trees I want to know I have a solid radio link.

I don't think being on top of a six story building should be an issue in and of itself. However, if it's like the apartment buildings/condos I'm familiar with, every apartment in it will have at least one 2.4GHz wifi network. We know that excessive 2.4HGz wifi signal can cause DSM signal loss. That's why Blade recommends against turning on Wifi video if you have a GoPro on their first camera platforms, and switched to a camera with 5.8GHz Wifi for the later ones.

You might take a portable computing device up there, and see how many networks there are.

Which protocol were you running because dsmx offers packet loss telemetry on the ultra micro's which might help determine if it's just some really strong interference in that area also what power setting were you running on? If I had to guess there may be a 2.4ghz security system in the area causing your problems.

I was using the DSMX protocol and I beleive 30mw power setting. Possibly 10mw, I'm not by my tx at the moment. And as for the wireless networks, there are literally hundreds. I can look at the wifi networks on my phone, then close and re-open the screen and there will be all new networks. I live no more than a half mile outside of downtown Houston in a neighborhood with predominatly 3 or 4 story structures, so flying on the 6th floor parking garage is one of the only open areas available. I had no idea wifi routers ran on 2.4ghz frequency. So is there anything I can do to prevent or reduce interference?
Also what power setting would yall recommend, and why?
How do I access the packet loss telemetry?

There isn't really anything you can do for interference except for upping the power unless you want change the antenna's. As far as what power setting that is kinda of a broad question using 30mw should give you more range than you can ever use on a ultra micro unless your getting interference in that case the more power the better. To use telemetry first make sure it's on by clicking on dsmx where you select the protocol then just go to the main page layout and set a box for "frame loss a"

The 2.4GHz (and 5.8 used for FPV gear) is an unlicensed band, so lots of thing use it. Wifi is either 2.4Ghz or 5GHz, and the 5GHz band includes the 5.8GHz used by FPV. Most residential wifi is on 2.4GHz, though very old gear may be on the 5GHz band, and newer stuff may be on both the 2.4 and 5GHz band. Other things that use the 2.4GHz band include bluetooth, wireless telephones, and other household wireless devices. As an added kicker, microwave ovens use 2.4Ghz to cook, so a poorly shielded microwave could generate a lot of noise.

I'm not sure how to deal with it. If you're using DSM2, switch to DSMX. With Spektrum Tx's, you need to give them time to find the best channels to work on before turning on the Rx. I'm not sure if that applies to the deviation implementation, but if waiting 5 or 10 seconds after you get the main model page won't hurt, and might help. Adding a satellite to the Rx might help, but I doubt if you can do that to a UMX model.

You might try calling HH support and asking what they recommend for dealing with 2.4GHz interference. If you can borrow a Spektrum Tx and see if that shows the same problems, it would help with that. I buy Horizon products in part because HH support is so good, and keep a DX5e around for testing new models on, just so I don't have to deal hear "We don't support that transmitter." If you're looking at a new UMX and the RTF version comes with something like the 5e, it might be worth getting that for future use.

Hi,
it always breaks my heart, when a bird crashes.
Did you manage to rescue your bird from that tree?

jacklscott3 wrote: Just like the first crash I was past the edge of the parking garage roof

Was this close to the place the first signal loss happened?

You could put your TX in low power mode, and walk around the parking deck with the RX in your hand and watch the LED.
Maybe there is a specific spot on your parking garage roof with bad interference.
Maybe the signal causing the interference is only there from time to time, so you may need to observe for a longer time.

i had signal loss on my bixler / blade 130x (Devo 8s), flying lovely then my plane went into a panic mode and crashed :/. In the end i found out that the wire in the aerial where it bends was damaged, wasn't snapped but had slight damage. Ordered another aerial and haven't had a issue.