R/C Tech Forums

R/C Tech Forums (https://www.rctech.net/forum/)
-   Nitro Off-Road (https://www.rctech.net/forum/nitro-off-road-130/)
-   -   Radio Electronics HELP (https://www.rctech.net/forum/nitro-off-road/249461-radio-electronics-help.html)

NCWC 10-23-2008 08:50 PM

Radio Electronics HELP
 
Futaba 3PK, Reciever is Futaba PCM 1024. Servos Are Futaba S9351 on steering, S9350 throttle. 1600 NiMH 6v Venom battery. I disassembled the radio tray for routine cleaning and inspection, everything passed. When I put it all back together just like it came out I turned the radio on, switched the car on and the transponder light came on but the servos did not center:confused:. I gave all the connectors a second look, everythings in the right spot and connected good. I even bypassed the switch with no luck. Both batteries are topped off. Thanks:)

mracer 10-23-2008 09:17 PM

Make sure you have the servos plugged in correctly. I know this sounds dumb, but you could have plugged the leads in wrong. I have fixed a few for people that this was the only problem. It is easy to get the leads turned around backwards into the rec. This will make them appear to be plugged in but they won't work. The black lead goes close to the outside of the rec.
Hope this helps.

NCWC 10-23-2008 09:42 PM

Thanks for the help but Futaba uses a tongue and groove type deal on the connectors, so i know they are correct. It seems like either the servos are not getting a power supply or the radio is not transmitting or the reciever is not sending a signal to the servos.

mracer 10-23-2008 10:02 PM

Sorry that didn't help. I am not familiar enough with that radio system to make anymore suggestions. I am sure tomorrow someone will be able to help you.

jamminnay 10-23-2008 10:24 PM

it may be possible that the rx and tx lost there bind.. i have had that happen with spektrum in the past.

NCWC 10-23-2008 10:35 PM

I dont think my radio has such a thing. Its not a 2.4 GHZ system

jamminnay 10-23-2008 10:36 PM

lol well i guess i should have read closer... i would say if our transponder light is on and the servos are not working the problem either lies with the crystals or the reciever

NCWC 10-23-2008 10:39 PM

Were getting closer:). I didnt think of the crystals. Do they "go bad" over time? The whole deal run like a top 1 week ago, and before i tore it down.

fiveoboy01 10-23-2008 10:41 PM

Do you have the wrong model selected in the transmitter?

Er I suppose it would still work with PCM though... But just a thought.

NCWC 10-24-2008 08:43 AM

Model selected is correct.

cjtamu 10-24-2008 08:59 AM

Servos aren't centering or just not responding at all? If your PT is on then you know the battery is supplying power to the RX. If the servos just aren't centering, it could be several things. First question is, did you turn on the radio and power up the car before you put the servo horns back on? You have to do that first, then put the servo horns back on in the same position they were in when before.

NCWC 10-24-2008 09:14 AM


Originally Posted by cjtamu (Post 4974070)
Servos aren't centering or just not responding at all? If your PT is on then you know the battery is supplying power to the RX. If the servos just aren't centering, it could be several things. First question is, did you turn on the radio and power up the car before you put the servo horns back on? You have to do that first, then put the servo horns back on in the same position they were in when before.

Thats what I was doin. After I assembled it i turned the radio then the car on to center the servos so i could put the horns on. The servos arent centering or responding to any throttle or steering inputs.

cjtamu 10-24-2008 09:30 AM

Take the crystals out of the receiver and transmitter and put them back in. While they're out, make sure that the crystals are on the same frequency. Are the servos getting power? B/c even if there's no radio signal they should get power, and they'll move or hum when you turn the switch on. How old is your battery? They go bad after while and it's possible the battery voltage is low too.

NCWC 10-24-2008 10:11 AM

Ive tried removing and reinstalling the crystals with no luck and they are of the same frequency. The battery is about 6mo old with about 1.5 gallons runtime. The servos are not making any noise when you turn the switch on. I believe there is no power reaching them.

cjtamu 10-24-2008 10:42 AM

It's weird that the PT comes on b/c that means power is getting to the Rx. And I know with the Futaba j-plug you can only put the servos in one way so it's not likley you fried them. Try plugging the battery directly into the receiver and see what happens. If you have another receiver try it and see what happens. You can also check the battery voltage if you have a charger that also discharges. Set the discharge at 0.5 amps and voltage cutoff at 1.0 V/cell. Hit the discharge and see what it reads. I had some goofy servo issues not long ago and when I tested my battery the voltage went below 5.0 immediately. Replaced the battery and it solved the problem. The only other thing would be, did you spray the receiver with anything when you were cleaning it?


All times are GMT -7. It is currently 08:24 PM.

Powered By: vBulletin v3.9.3.8
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.