Brain Dead 4-In-1?

[MAXXED]

My Blade CP 4-in-1 seems to be developing peculiar symptoms as it gets older.
It worked perfectly when it was new, but after many crashes :roll: and mileage, its behavior is getting a little strange.
When I first plug in the battery and spool it up, the gyro and proportional control are totally out of whack for about 30 seconds to 1 minute. The tail will be all over the place and impossible to control, as well as any cyclic controls.
It's like the Blade is having psychotic episodes.
Then after a minute, everything's fine! :?
If I do any upgrades, repairs, or fixes to the Blade, the same symptoms appear, but refuse to go away until a crash.
It almost seems like the impact is jarring something inside the 4-in-1 that's loose, and knocking it back into place.
Anyone else experience these symptoms? :?

[eddiemoth]

MAXXED, This is a common problem. I experienced that problem too awhile ago. People use words "my Blade CP has its own mind" or "my Blade CP is possessed" to describe the problem. Some people have to get a new 4 in 1 but my problem was caused by the fully charged battery li po. My problem always occurred when my TP battery was fully completely charged. I tried it with my RC-expert (weaker one) li po or less charged TP battery Li Po and I did not have the problem. So I did not fully charge my battery and if it is, discharge it a little bit, disconnected and then the problem was gone. Exactly like you said the problem happened the first minute and that is when your battery is fully charged.

It is hard to say if the 4 in 1 or the battery li po that has problem. I still use both my old 4 in 1 and old TP battery and don't have any problem any more. So try not fully charge your battery or use a different battery li po and see if it is difference. If you have the problem, disconnect the battery, let it stand a a couple minutes and then connect it again. I hope it is not your 4 in 1 problem.

[MAXXED]

eddie,

I think you hit the bullseye!
You're right, the Blade is really hard to control on a fully charged 3 cell li-po, but it calms down quite a bit when the battery stabilizes and drains off some capacity.
I wonder if going to a 2 cell li-po to drop the voltage would cure it? :?:

[eddiemoth]

MAXXED,
I think it will solve problem except I have never tried it before. A two cell li po pack would be compararible to the stock Ni-MH 9.6V except it is lighter in weight. The light weight should compensate the lost voltage so I would try it if you have a two cell pack handy. If you are going to try, let's us know what you find out.

[Sleepstalker]

Nice call fearless leader I haven't heard of that one...I wonder if Horizon is using the exact same 4 in 1 on the new Blade CP Pro?
I read that an upgrade to a good HH Gyro is easy to do on the CP Pro so maybe a different 4 in 1 config? If anyone can comment it would ALWAYS be appreciated...Sleepster... 8)

Also its kind of ironic that the other major 4 in 1 problem which is heat related seems to work the exact opposite , so when you first start hovering everything is ok for about a minute then the tail or the whole Blade will start to drift a little and need constant trimming and acting like "it's got a mind of it's own". Many have corrected this by ventilating the heat build up around the 4 in 1 by either removing the whole 4 in 1 case or by carefully drilling holes in the case and sometimes in the canopy also...Sleepster... 8)

[swatson144]

It almost seems like the impact is jarring something inside the 4-in-1 that's loose, and knocking it back into place.

I'd have to have a hard look at the crystal, with those symptoms. If I remember correctly they are mounted in a hole and have a cap that secures them. It's a good idea but may affect the survivability in the rigorous landing schedule while learning. Crystals aren't very tough and it's normal to replace them after crashes in bigger more costly birds.

I know it doesn't jibe with the 1 min thing you were talking about. It is amazing sometimes how we can decide it is power related instead of control.

Just a thought

Steve

[MAXXED]

eddie got me really curious about investigating this issue, and I made some interesting discoveries.
The 4-in-1 is indeed a little more twitchy in response on a fully charged 3 cell li-po, that packs 12.56 volts on my voltmeter.
As the voltage drops down close to 11.1 volts, everything does settle down considerably.
My Thunderbird ESC's low voltage cutoff kicks in at 10.6 volts.
After doing some research, I found a cure for the "brain dead" behavior of the 4-in-1.
The problem is the proportional and gyro gain pots.
They are very susceptible to our salty and moist Hawaiian weather.
I read a post where 3-in-1 oil was used to lube the pots, with good results, but I don't recommend it on electronic components.
I used an industrial grade electronic cleaner/enhancer/moisture displacer on the pots, and worked them back and forth.
You could also use an electronic contact cleaner or TV tuner cleaner from Radio Shack.
Problem solved!
The 4-in-1 acts like it's brand new again! :D

[eddiemoth]

Great detective work. You sounded like a scientist!