Beige

My 9CAP is exhibiting something odd that i've never noticed before,

I was at the field, engine started ready to tinker with as the Tx battery was too low to risk flying (8.7v) when out of nowhere the Tx stopped transmitting and randomly beeped, previously the Tx will keep transmitting, only at a gradually lowering power well below 7v after the LCD has gone out and a warning beep has sounded.

I switched it off and on, still no RF... I took the module out and popped the crystal out (I'm in the UK remember) and checked out the contacts, all appeared fine so i put it back together and still no RF... So again i took the module out and bent the pins a fraction of a degree to the side put it back in turned on and had RF back, gave the module a wobble and couldn't disturb it.


Unless there some strange routine in the firmware that i've managed to run i'm thinking it's a hardware issue, that or the pin tweaking was a coincidence


I've currently got the Tx battery cycling on a charger so we'll see what it's really like.


Lastly, who repairs Futaba radios in the UK, Ripmax of course don't seem to want to know



*EDIT*

Maybe this should be in the Futaba support forum, oh well, I'm sure some kind mod will move it if they see fit

pilotpete2

Hi Ice,
Since this occurred while the battery voltage was too low to fly safely, I wouldn't sweat it too much.
As it seems that reseating the crystal made a difference, possibly a little resistance had built up on the contacts.
BTW, on this side of the "pond" there's no problem popping out a crystal, as long as you put the same one back in
Cheers,
Pete

BuschBarber

My Feedback: (2)

I have seen some strange things happen when my 9C Tx battery is too low. Either channels will not respond or they will hesitate and move by themselves. Mine is 72Mhz, although, I do not think that makes a difference.

I am currently using a 2 cell LiPo battery from TrueRC.com. It charges up to 12.4v and I recharge at 11.1v. I was using NiCad and NiMh before that.

LesUyeda

I really do not know if this applies to the 9, but the early 8UAF's had a pin problem. The antenna mount was the support for the lower section of the printed wiring board that the RF module pins are soldered to. As the antenna gets pulled out, and pushed in, the board is moved slightly, until the solder at the pins fatigues and fails. If it were mine, I would take out that board, and use an ocular to examine the solder joint at the board.

Les

sfsjkid

I agree with Les, never had the problem with my 9C, but had a similar one with the 9Z. I think depending on the frequency of replacing the module and/or even the method, the pins or possibly the connectors in the RF module is a point of failure.

Good luck!

Beige

The battery is getting about 500mAh in it before it peaks from a complete discharge, and considering it's an 800mAh i'd say it's had it

However, with the battery fully charged i can't provoke any kind of reaction so it looks like a new battery is in order.


Oh, i also stripped it down and had a close look at any points of posable stress on the pcb and didn't see anything of concern

sfsjkid

The pack may be on its way out but what voltage are you getting? Just double checking but when you say "points of possible stress" you mean you looked on the back of the pcb and looked for solder joints that were loose (a magnifying glass may help)? Also, the connections in the rf module may be at fault too.

pilotpete2

No, fortunately the 9C does not have that issue, the antenna mounts to a heavy plastic mount that's part of the front half of the case, and has a wire running to the board that the RF module connects to. That wire should be checked to be sure its tightly connected.
Your bringing up that issue made me think, and then I remembered that I wanted to convert my throttle to a smooth Heli throttle, so I had a good reason to open the case, job done. Thanks for jogging my memory
Pete

sfsjkid

Pete the problem is not with the wire but with the pins the rf module plugs into, you know, those things that stick out with the module removed. It is possible to "crack" the solder on those pins by plugging the rf module in and out depending on one's ham-handedness or shear bad luck.

pilotpete2

Good point, mine were fine, but I'll keep that in mind, as I currently switch between a fasst module and 72Mhz a couple of times a day at the field.
Pete

Wait a minute, what's with this ham fisted stuff, who moi
"If it ain't broke, yer not trying hard enough"

Beige

I can't remember the exact voltage, but somewhere around 11v just off charge, no dead cells

And yes i checked the base of the pins, just so you know, electronics is one of my hobbies so I've a good idea of what to look for



I'll go out with a park flier when i get another Tx battery and see if it does what it should.