JR 12X LCD Flicker/Click - No RF?

[Snowflake6515]

I vaguely recall reading (no joy searching, however) that some 12X radios have a problem with the LCD screen flashing on/off and/or the screen going blank.

My 12X started flashing about once per second with an audible click. It kept doing this and the RF (blue light indicator) did not come on. That had happened after flying one of my helis and then changing models to fly something different.

The XMTR can turn on in "setup" mode, but not in regular mode. When I charged the XMTR battery, I noticed that, after about one-half hour or so of use, that the voltage indicator drops below 9.1 volts, there is a flash/click with the LCD display, then the RF turns on, the screen shows the status and the voltage rises to 10.1 or 10.2 volts.

I called Horizon Hobby twice and recieved two answers: (1) bad cell in XMTR battery (only been charged with supplied charger) and (2) something wrong in RF section that it is drawing too much current.

I should mention that this problem only started, and is reproducible, when the weather dropped to about 40o F.

Has anyone else had this problem? If so, what was the fix? I've read the LiPo thread and might just go that route if it is a bad cell in the NiMh pack. However, if there is a fundamental flaw then it needs to be repaired.

Thank you.

Michael

[Snowflake6515]

Update: Bottom line? No change. The unit was returned to Horizon Hobby and I received it in time for the weekend flying. The tech report said that the battery had come loose and simply press it firmly into the slot and that will "fix" the problem. Total BS. If the battery was loose, on their end, it probably happened during the shipping for repair.

I charged the XMTR battery, and rebound some models, spending about 45 mintues with the RF section on, in total, About 20 - 25 minutes into the rebinding, setting paramaters, etc., when switching from system mode to normal mode, I would get one click/flick of the LCD screen. I started to worry about the "repair".

I left the XMTR in the garage overnight (about 45oF), with around 9.9 volts still showing at shutdown, but this morning, as I made my checks prior to going out to fly, the XMTR will not turn on - just a constant flick-flick-flick of the LCD screen and a clicking sound. No RF, no screen, totally useless radio.

I'm really stuck, folks. Does anyone else have any ideas? I cannot send it back becaues Horizon Hobby has proved that they are completely incompetent with respect to this radio.

Thank you.

Michael

[CSWHITING]

I Seem to have same issue with my 12x when its cold and the voltage gets below (9.2v) my screen flickers and goes blank i thought the battery was the problem. I was investigating lipos but dont want to void warranty. Not happy about your experience with the repair?

let me know if anyone has come up with a good solution.

[Snowflake6515]

Update: I figured that maybe the battery (NiMh) might be at fault - bad cell, perhaps. So, I figured for $80 I would try a new battery. I ordered it and, when it arrived, I could not charge it - blown fuse in a brand new, out of the box, battery. Returned it and Horizon Hobby is going to reimburse my charges. I ordered a second battery and charged it with my DX7 charger for 24 hours. I plugged it into the radio and it seemed to work, so far; several flights today.

I now have it in the garage overnight (about 45oF) and will test it tomorrow.

I, too, am thining of a 2S LiPo with two of the 1N4001 diodes in series to drop the voltage to avoid an overvoltage situation. I'll post my findings after the cooler temperature overnight...

[Snowflake6515]

The battery must have been the culprit as I've had ZERO problems with the LCD flickering / clicking and it holds its charge even in cold weather. Now, if only I could get HH to reimburse me for purchasing an extra battery to prove that they could not solve the problem.

[zeb29]

I know this is an old thread, but I'll tell you that my experience is similar to yours only I also had servo settings getting corrupted. Not that the ATV settings changed, but the actual servo travels changed.

I sent it back to Horizon and it came back to me with a note saying they could find nothing wrong and had done a low battery check, but when I pulled it out of the shipping box (it was a bit cold) the radio would not turn on again.

Much gnashing of teeth on my part but one of the Team-Horizon guys picked up on one of my bitching threads on a forum. Got with Jodi who runs Team-Horizon and we did some testing. It had a bad battery.....

Neither your nor myself are the first I've talked with about bad batteries on the 12X, but most of us have started using the DX-7/X9303 walwart for charging as I think the included charger which puts out 250mah at 12.0 volts is just too much. My battery always got really hot when charging and that's a classic case of overcharging high capacity NiMH cells.

I also got a 2700mah battery pack from NoBS and found a new walwart JR just came out with that's 270mah output at I'm guessing a lower voltage since there are no specs on the charger for voltage like in the past. That walwart has a warning to not leave it on for more than 10 hours, only gets the batteries slightly warm when charged which is supposed to happen and is a bunch faster than the 110mah unit from the DX-7/X9303.

Your choice, but I think the 12X included charger is what's causing the problems and I've not used mine again.

[Leon Luke]

Hey snowflake, and others that have noticed the flicker in cold temps and low votage, after replacing the battery have you guys encountered any more problems? I too have just experienced the same issue after a full charge. I think it is an intemittent bad cell in transmitter battery. The screen would flicker on and off, and the rf would not light up blue, although I could access the setup screens. When I got home I plugged in the charger and after a few seconds the screen lit up and transmit blue led came on. When I unplugged the charger, and let the voltage drop, I turned the unit off and on, but it would do the same thing...flicker. As soon as I plugged the charger back in the thing would light up normal. I guess it is the battery. But funny thing is the battery seems to be rejuvinated with only a few minutes of charging, and now it has held solid at 9.5 volts for over an hour. It seems like the battery has an intermittent bad cell.

[zeb29]

Just re-read my post, it'll fix your problem if you proceed as I suggested to snowflake....;)

[Ah Clem]

My transmitter did this for the first time today.

This thread was a goldmine. From what I can tell, when the transmitter is turned on, the RF deck draws quite a bit of current when starting up. When I got mine to start again (after sitting for an hour or so) the voltage dropped to 8.8 as it started up. I would imagine the threshold for starting is just under that.

I examined the JR transmitter pack and found a small white component in series with the cells-can anyone tell me what this is?

Horizon, per their website, appears to be out of transmitter batteries. I would substitute a different brand of Ni-Mh or Ni-Cad, if I can identify what this component is and if it is necessary.

Thank you all in advance.

[zeb29]

The voltage difference between when the tx is first turned on and then goes to it's transmit mode is the key to finding the battery issue if you ask me. When my radio was new, there was a .5 volt difference between booting up and when it started transmitting, i.e. 9.8 volts during boot up and 10.3 volts when it started transmitting. When I started experiencing problems, that difference was .9 volts and it was taking a long time to come on, about 6 seconds or so.

With the new 10X pack, the voltage difference was .1 volts and it turned on in half the time, about 3 seconds. With the new NoBS pack as well as the new JR pack, that voltage drop is .2 volts (not an unusual difference since you're dealing with NiCD on the 10X pack vs. a NiMH pack on the NoBS and JR packs) and it still turns on in about 3 seconds.

Not working when cold is another key indicator I had and it makes sense as lower temperatures affect battery performance.

Can't tell you what that part is, but I just sent my cassette off to NoBS batteries and they installed the Sanyo 2700 mah cells in it. You can either order the cells from him and install yourself, or he'll do it for free if you ship the cassette back to him.

I also got a new 2000 mah from Horizon, but when I experienced my problem they were out of 12X packs then too so I used a 10X (they're 1100 mah NiCD) pack I got from a local guy until I got the other packs.

JMHO, but I'd not use the included JR 12X specific charger again if I were you...