FASST and FrSky signal strength

[cymaz]

In a lull in today's flying session, (these, by the way, can last several hours due to talking and eating cake) the subject to failsafe and signal re-establish times came up.

So a couple of us conducted a small experiment. My Wot 4 XL has a FrSky TFR6 Rx powered by an Enenloop 6v battery. The Tx is a Futaba 9cap with a 8ch 2.4 Futaba module. Both batteries fully charged.

The plane was turned on along with the Tx and then it was then placed inside my aluminium case. Signal was perfect. The Tx case was then placed in our club hut, the opposite end from the shipping container-doors open.A distance of about 30 ft... Signal perfect. As soon as we shut the container door the plane went into failsafe. Within 1/2 second!!!

Now the important bit....as soon as the door was opened the full signal was restored.....within 1/2 second. The door needed just opening, opening it wider made no difference. The tiniest amount was enough.

So, the conclusion is?? If the plane went into failsafe when flying would we ever know about it?? I don't think so. Not with this set up probably. The rebinding in and out is almost instantaneous and if it did occur then I might think it was turbulence or wind effect somehow. It proves to me that the 2.4 signal we have in our set ups is very good.

Any thoughts??

[john stones 1 - Moderator]

Yes, i think they're very good as well

[Engine Doctor]

I have used FrSky with my Futaba FF9 and the reboot times as you say almost instantaneous. Brilliant kit ! Only had a couple of failsafe episodes in many years of flying with it and won't be changing anytime soon.

[Denis Watkins]

You are right Cymaz, fades do occur that you may not realise

Some Tx can record these and at the end of the flying day there can be dozens on the readout

And the flying has been completely unaffected

Edited By Denis Watkins on 01/04/2017 18:40:31

[cymaz]

I thought that by doing the test in some sort of order would make sense of the results. And I think it has.

Has any one done anything similar??

[john stones 1 - Moderator]

No Cymas your club huts too far away

[Former Member]

[This posting has been removed]

[Biggles' Elder Brother - Moderator]

With FrSky Taranis we have RSSI telemetry which can be data logged. I have done some tests with this at our field. We have a corner of the field that traditionally is known as the "corner of death". A disproportionate number of models have "gone in" in this area. Fortunately it a far flung corner and so it tends to be avoided.

I decided to turn on the RSSI telemetry with data logging and fly a raster sweep pattern around the field to see if I could indeed confirm that the said corner was a low signal zone. The results were very interesting.

1. There was no evidence at all that the signal was on average any lower in the corner in question than any other point ssimilar distance away.

2. Signal strength could vary apparently randomly by 3-6dB with time in the same spot! Bear in mind a 3dB signal strength change equates to approximately a 50% variation!

3. On at least one flight the Rx went into failsafe - and emerged again. I had no idea it had done that - I noticed nothing out of the ordinary flying the model! Now OK - had I been in mid-turn I might have noticed something - but flying straight lines on this raster scan - nothing. The time stamp indicated that the "outage" lasted approximately 2-3 seconds - quite a long time in reality when flying a model!

As Cymaz has suggested it prompts the question how often does this happen and we just don't know the recovery is so good?

BEB