JR 2.4 Ghz ISSUE

[onecan]

Hello

I have taken the plunge to JR 2.4 Ghz over the past month shifting all my planes to it. So far I have flown smaller glow models and electrics with no issues.

I am running a JR DSX9 transmitter which is basically our version of the 9303 2.4 and using JR 921 RX's. I installed a 921 rx with 2 satellites and a glitch counter into my 40% Comp Arf Extra last night and headed to the field today. I did an 'advanced' range test using the glitch counter while rotating the model around in circles for 1 minute as advised and got an acceptable level of lost frames on each RX with no total frames lost and no holds.

However I did another test with the engine running (TX at 30 paces with the bind switch in, while rotating the model around for 1 minute) and got 452 lost frames!!

So I fired up the DA150 again while standing right next to the model (NOT holding the bind switch in) with the glitch counter on the F mode and it was acting like a rev counter!! The more you rev the engine the faster the lost frames counter would climb .... doing this test I had no lost frames on any of my 4 RX's but the 'F' count was in the hundreds!!

Needless to say I didn't fly the model like this. I have included 2 photos showing my RX installs (sorry about the quality it was taken with my phone). What on earth could be causing this??

My setup is a JR EQ10 Power expander with Super Reg and 2x Fromeco 5200's for the batts. It has a Smart-Fly optical ignition cutoff, so can't see any noise feeding back through this to the RX.

This has got me baffled and rather nervous!!

Thanks in advance,
Jonathan

[RustyTumbles]

Not really sure. At first though maybe the fact the main RX is down behind the tank, but on my WH Sukhoi my main rx in down behind the tank also. Do you know what aerial is the worst or is it a constant over all aerials? From what I have read and heard 0-7 frames lost in a flight is not uncommon.

Here are my data logger figure from my last flight today.

A: 67
B: 137
L: 47
R: 15
F: 001
H: 000


and a few pics of my install.

[onecan]

Thanks for the quick reply Rusty

During my engine off range test the main RX down low was missing frames really bad, my numbers were something like:

A: 136
B: 252
L: 36
R: 12
F: 0
H: 0

Which I thought wasn't too bad and probably to be expected, given as you say the main rx is located low beside the fuel tank and there is a strip of carbon moulded into the fuse on the other side. However the 2 satellites, 1 up high and 1 in the turtle deck were good and low so that was ok.

Then I though I should try a engine on range test which resulted in massive frame loss, but the really weird thing was standing right beside the model on the ground (WASN'T holding the bind button) and revving the engine which resulted in the following figures after about 20 secs of engine running:

A: 0
B: 0
L: 0
R: 0
F: 284
H: 0

And as I mentioned earlier the F reading was like a rev counter, the faster you ran the engine the faster that number climbed. At full throttle those figures were flying through!

Its got me buggered .....

Jonathan

	Quote: Originally Posted by RustyTumbles
	Not really sure. At first though maybe the fact the main RX is down behind the tank, but on my WH Sukhoi my main rx in down behind the tank also. Do you know what aerial is the worst or is it a constant over all aerials? From what I have read and heard 0-7 frames lost in a flight is not uncommon. Here are my data logger figure from my last flight today. A: 67 B: 137 L: 47 R: 15 F: 001 H: 000 and a few pics of my install.

[RustyTumbles]

I guess you may have to go through the usual stuff like plug caps, ignition leads, kill switch etc. maybe try getting the main RX up higher above the tank, but from the engine running figures it seem to me like a engine/vibration issue. Keep us posted on your findings.

[RustyTumbles]

Is this the same model you flew at the DA challange last year???

[Stu_D]

Jonathan , I'm with Rusty on this one . It looks like a loose connection with
the count going up with the vibration increasing . Its always a hassle when
all the leads are bundled together , if you pull on one who knows what other
leads have been effected . Your side aerial from the base receiver also look
to be pushed up at 90 deg not out to the side as it should be .
There have been some cases of poor performance when the transmitter
is low on voltage as well .

My installation is almost the same as yours and its 100% fine is so I would
lean more to a loose lead or plug as Rusty said .

Stu

[onecan]

	Quote: Originally Posted by RustyTumbles
	I guess you may have to go through the usual stuff like plug caps, ignition leads, kill switch etc. maybe try getting the main RX up higher above the tank, but from the engine running figures it seem to me like a engine/vibration issue. Keep us posted on your findings.

Thanks Rusty, I will go over the whole ignition setup and see what is going on. I have a spare ignition so I might throw that in there and see what is happening.

	Quote: Originally Posted by RustyTumbles
	Is this the same model you flew at the DA challange last year???

Yep thats the same 260 that we had at the DAC last year.

	Quote: Originally Posted by Stu_D
	Jonathan , I'm with Rusty on this one . It looks like a loose connection with the count going up with the vibration increasing . Its always a hassle when all the leads are bundled together , if you pull on one who knows what other leads have been effected . Your side aerial from the base receiver also look to be pushed up at 90 deg not out to the side as it should be . There have been some cases of poor performance when the transmitter is low on voltage as well . My installation is almost the same as yours and its 100% fine is so I would lean more to a loose lead or plug as Rusty said . Stu

Thanks Stu, I will check the whole thing out. As you say it is a real pain with everything bundled up together but it sure beats the alternative!!

Thanks Guys,
Jonathan

[3dubya]

Hey onecan were you getting glitches on ur old mhz freq in it..

[onecan]

	Quote: Originally Posted by 3dubya
	Hey onecan were you getting glitches on ur old mhz freq in it..

Hey TD

I used to get a glitch occasionally while low around the back of a roller, it would be a hit of failsafe (throttle to idle) but other than this is was rock solid .... 2.4

The 2.4 was still working fine yesterday and if I hadn't had the glitch counter in it would have just flown the model, but seeing this frame counter acting like a rev counter didn't exactly turn me on!

1CAN

[JimC-MD]

I am not sure about this.......

Based on your description, I might try another flight log. I wonder if the problem is the flight log itself showing the lost frames without the RX units seeing anything........

Just a curiosity and a cheap test.

[onecan]

	Quote: Originally Posted by JimC-MD
	I am not sure about this....... Based on your description, I might try another flight log. I wonder if the problem is the flight log itself showing the lost frames without the RX units seeing anything........ Just a curiosity and a cheap test.

Hi Jim.

I will try this out aswell, I brought another flight logger for a mate when i got this one so I will get that and try it also.

Cheers,
Jonathan

[3dubya]

	Quote: Originally Posted by onecan
	Hey TD I used to get a glitch occasionally while low around the back of a roller, it would be a hit of failsafe (throttle to idle) but other than this is was rock solid .... 2.4 The 2.4 was still working fine yesterday and if I hadn't had the glitch counter in it would have just flown the model, but seeing this frame counter acting like a rev counter didn't exactly turn me on! 1CAN

ha ha yer the logger may be a bad thing, too much info, i had some small glitch probs all of a sudden in mine on 36mhz, i had just changed me ignition and was suspecting new ign-cap was dogey, but was told if ur ign-caps are bad you couldn't walk 10 feet without plane going nuts. So i plunged for 2.4 for i didn't want to piss around all day trying to find small 36mhz rf prob, all ok so far on 2.4 FASST.