Problems with Futaba 3PJ
 

Anyone using 3PJ with PCM receiver? Is the failsafe built-into the 3PJ very sensitive? I can't operate my car more than 10ft away without the failsafe kicking in. I tried at 2 diff. areas (Perling Leisure Mall and Bkt Indah Clubhouse, JB) and the same thing happened. I don't believe it is any real interference. Could the failsafe function/unit be faulty? I tried changing antennaes and it still won't work beyond 10ft. The crystals are 40 mhz channel 67 (what is the exact freq. huh? is it 40.670?). The Rx module is PCM and the 3PJ is set to use PCM. The RF LED is lit up fine i.e; signal strenght is OK. All the batteries (Tx/Rx) are fully charged. I haven't tried it without the failsafe function yet.
:( :( :( :(

any help appreciated.

tq

I used to have a 3PJS with PC receiver without such problem. The failsafe is working, but your range of 10ft is far too short. I really like PCM failsafe, especially you can let it go to a pre-set position.

Go back and find your seller to remedy.

What servo u using? Im using S9450. just broke the casing..Anyone know what the parts number for S9450 casing or other Futaba Digital casing will do?

I am using the same device as yours & was faced with similar problem once. It was due to my antenna wire close to breakage with a portion inside the receiver dangling. But not quite sure if you are facing the same cause. Anyway, you may want to check the followings:

1. Wiring harness between batts & receiver, receiver & antenna. The wires should be in good cond. & not rust / rot / close to breakage at any point of it.

2. Try with the batt. failsafe & freq. failsafe function off. This will shortlist the problems.

Hope these help, cheers!

I do not own a 3pjs, but I just can't ignore your problem, I have a same thing with my M8 once, I found out the problem is with my crystal, after using the crystal for a long time, it might have some internal cracks. I change the crystal and the problem is solved. Have you tried changing your crystal yet?

Thanks a lot for the response you guys, I really appreciate it. I've tried with the failsafe off but I still lost control beyond 10ft. I haven't tried changing the crystals but I got in touch with the seller and he's bringing replcement crystals to help troubleshoot the problem. Will any 40mhz Futaba crystal set do or is there a specific type for PCM? Also, the Rx wire/antennae sure looks skimpy, so I'm starting to think its because of a short Rx wire. However, the RF indicator in the LED is lit up, so doesn't this mean I'm getting good transmission? As for wiring between Rx and battery, since servos work fine (at short range), I assume Rx is getting enough power. My servo is a Sanwa ERG-VB and a TowerHobbies S3K. Someone else on another forum said the Rx might need to be re-tuned(?) and apparently, only Futaba can do this. Is there an authorised Futaba service center in Singapore? I've narrowed down my next plan of action;

1) change crystal set
2) replace Rx wire
3) replace Rx

Whatelse?
ok, hope it is something replceable and not a problem with the circuitry etc.

have a 3PJ myself. suggest, u try swopping crystals .. u'll be surprised at how sensitive they can be. when they work well, they give no probs. but if they are cracked, etc .. it's hell trying to trouble-shoot.

not sure if u need to get original futaba crystals? but FM/PCM use the same crystals, as far as i am aware of.

also, go scrutinise the antenna wire CAREFULLY.