Hitec Digital Problems

[jimbob]

I have just replaced the servos on my R50 with brand new Hitec HS-5925MGs on the cyclic and collective. These servos are rated 0.1sec/7.4Kg at 4.8v and I thought were a bargain at £50 each...

DISASTER!

Just went for a test fly, and found that when slowly moving the pitch up and down I would get a big glitch on the pitch and other controls too.

Could this just be a duff servo, and has anyone else used the Hitec Digitals to good or bad results?

Incidentally, I still have a smallish battery pack, but it was fully charged so dont think it was a problem.

Any comments appreciated....

Jim

[Ade_Law]

i am willing to place money on the fact your running PPM. I have seen exactly this problem.

a larger battery might well help the problem, minimum of a 2000mah sub-C sized nicad.

adding a PCM rx will cure the problem.

Ade

[ChrisB]

A friend of mine did have a dodgy servo that was causing glitching in other channels,i cant remember the make though,it may have been cough,cough Supertech but im not 100% sure..

[Ade_Law]

now chris... admit it... it was you and you bought a supertech servo :-)

Ade

[ChrisB]

No no not in this instance,the only Supertech i ever actually purchased was their `fast` one to try on the tail and it failed,the person in question was John Man,,,

Im a FOOTABA man now,first their gyros,now their servos,what next,,your are a terrible influence

[Ade_Law]

14mz :-)

Ade

[antsis]

I'm running 5645's on the CCPM and 5925 on the rudder of my pred along with a 2000mA 6V nicad and Futaba PCM receiver. Not had any problems.

[ChrisB]

14mz!!!!!

There are several things i would spend that sort of money on before one of those,i only want my Tx to control my heli not play music or display pictures and talk to me when i flick a switch

[jimbob]

You are correct that its a PPM receiver Ade, but I'm lost as to why the modulation system make a servo act oddly though?

I can swap to a PCM rceiver to try and see if it goes - do you know what causes it with the PPM?

Incidentally, its a dual conversion reciever - could that make a difference too? I can only surmise that its some kind of intermodulation problem...

Its ironic that my ancient Baron 30 with 148s all round, a coked up TT engine and a bent main shaft flies better than my digital R50 at the moment...

[jimbob]

Put a PCM rx in and so far it all seems ok - much less twitter on the servos, and no glitching as far as I can tell.

Lets wait and see, but it looks promising!

Latest news... all seems fixed. Very odd!!!

Oh well, now ive got a new PCM receiver and a 4100maH NiMh in both R50s at least they are almost the same spec.
Now all I need to do is get the clutch issues sorted and I'll be a totally happy camper

Thanks for the advice chaps.