DX8 Need I Be Worried?

[Tripler]

As I said in another thread today.
Had my first real play with a DX8 and 6 today and had to keep re-binding.
Thought it was me doing something wrong but turns out it does happen with spekkies.
Never ever had to re-bind with any models using my Futaba 10c or worry about the rx position.
If someone asked me to recommend a TX, you can guess which one it would be.

[vtrnutter]

So no inverted flying with a DX8 ?

I'm talking about the antenna on the TX, not the RX.

[Mslater]

I'm talking about the antenna on the TX, not the RX.

Yes but is it just coz it's pointing up or is it because it is in the same orientation as the heli ?.

ie. If you fly inverted do you get best signal by pointing the TX down ??

[3d_willz]

i had a dx8 and it was perfect no probs at all but once i stated seeing all the probs slowly arrising i thought shit im getting rid b4 its not worth as much. the dx8 was only my tx for the halls so now thats gone i got the UGLY bastoooood dsx11 and my ole spunker tx.

[vtrnutter]

Yes but is it just coz it's pointing up or is it because it is in the same orientation as the heli ?.

ie. If you fly inverted do you get best signal by pointing the TX down ??

The article I quoted earlier shows how you should set the antenna on the main RX and satellite so that they are perpendicular to each other. That way, no matter what orientation the heli is in, you get the best reception.

The same is true on my RC cars - the antenna / RX should both be pointing straight up for maximum range - something to do with the 2.4 wave length apparently.

[Mslater]

The best diversity for aircraft is two antenna at 90 degrees - and always away from the carbon frame.

2 antenna are needed to avoid destructive interference from reflections of nearby objects.
90 degrees is required because the signal is polarised.

Also to note is that of the two wires from a spektrum rx only 1 is the antenna - the other is ground.

[Nick B]

Been using mine for a good 3 months now and have put many many hours on it.I only use spekky rx's with careful placement.

No probs so far

[wearypanda]

I have had mine about 4 months and have used it a lot. I have had two issues:

1. Lost range, discovered the ariel had come unplugged from the PCB. Put it back in and added a little hot glue to stop it happening again.

2. Just last weekend the aileron pot started glitching and not centering. Deviation of up to 23% seen on monitor. Had major trouble landing safely and it could have been the cause of a rollover the weekend before which I had attributed to mistakenly binding my SK720 in high res mode.

So, I love the radio, it feels right, has great functionality for the money and I feel very much at home with it. However, it's a bit like discovering that your partner has been having a bit on the side; I am just not sure if I can ever trust it again. This means that it will be difficult to relax again while flying with it. Not sure what I will do, but I am certainly thinking about alternatives, in particular the Aurora 9 looks like a good option.

[Mark_T]

Not sure what I will do, but I am certainly thinking about alternatives, in particular the Aurora 9 looks like a good option.

Just for balance, I have the Aurora 9 and I've experienced zero problems with it, but for interest I spent some time today measuring the output from the aileron / elevator / rudder channels and comparing the accuracy of the DX8 and the A9 for centring and holding the centre on one axis while moving on the other axis of the sticks.

Interestingly the A9 was not as accurate as the DX8 but this was almost impossible to see if you only had the radios own monitor screen to work with as unlike the DX8, the A9 does not try to give you a numeric indication, just a bar graph.

So while the DX8 might flicker slightly between two numbers you'd see nothing like that on the A9 even though the actual output was not as stable.

I'm beginning to wonder if Spektrum have caused some problems for themselves just by trying to express in percentage terms a value that will alter slightly due to the mechanics involved in the process and are thus giving people a feeling there is a problem when one does not actually exist.

Obviously when people see movements of 5-10% and above there is a real problem, but an apparent 1% movement either way could be something a lot smaller just on the edge of being rounded up or down.

The numbers give a false sense of accuracy (or inaccuracy in this case) for the DX8.

[wearypanda]

I agree with what you say about 1% or so variation from neutral. I would almost expect this as a result of the mechanical 'slop' on the gimbal mechanism. My issue gave much bigger and rapidly changing (from negative to positive too!) values with up to 23% off centre. Actually the first place I spotted it was when I connected the SK720 to my laptop and ran the Skookum configuration program. Here you have a visual indicator of the radio output and I could see straight away that something was seriously wrong.

[pgkevet]

I know these polls are always skewed.. but half the onwrs with problems and 25% no longer using it...that's high by any standard.

Just as a statement (not pushing futaba) but my FG12 gives both graph and percent figures on output and is normally rock solid. When it is currently having issues then both the graph and the cyclic numbers jitter by a few points... service tells me the pots probably worn from use/abuse in the 2.5 yrs I've had it.
My point here is that it may be a good habit to check that screen as part of the preflight. I've been doing that this w/e anyway and just flying little 'uns... it's been solid all w/e - reassuring before you arm the heli.

[Mark_T]

I know these polls are always skewed.. but half the onwrs with problems and 25% no longer using it...that's high by any standard.

Got to love statistics

From the same numbers you can also say 'over 75% using it happily'

[pgkevet]

Got to love statistics

From the same numbers you can also say 'over 75% using it happily'

Or ONLY 75% using it happily - politics :-)

[Wot_Happened?]

I've been watching this and other threads with growing concern - I had a DX8, I bought back in February this year - only charged the Tx battery to check the Tx out, I've been waiting for the dust to settle on these 'fixes' and ongoing issues.

Then I received the email about checking the PID and returning to HH for software update( I checked and mine was for recall) - then I saw the Gimball checking as well, tried the link to get return info - web link failed.

I bought my DX8 from Sussex Model Centre and decided to take it back yesterday (4th June) and see what they could do - they gave me my money back - no problem, no hassle. I would like to point out that I do not know if my DX8 had any 'issues' - I bought it to fit to my TRex 700E FBL (esp looking forward to looking at the logged data ). Still using my trusted DX7 .

In the end I weighed things up and thought that if anything were to happen as a result of the Tx going wrong I could not live with this - esp if someone was hurt - never mind the cost of repairs.

Big thumbs up to SMC.