Force fx black series issue

[Hefty]

Hi,

I don't know if it's the right part of the forum to post this, let me know if it isn't.

So i got a Darth Vader force fx black series saber and i wanted to use the circut board  into my Dark Initiate LE v4. i tested off the hilt my board with the switch and all and it worked. so i decided to install it into my hilt and it stop working. i don't know if i broke the board in anyway and i would like to know how to troubleshoot my board. i tried the test points and all seemed to give me some voltage reading (3.3-7.4 depending on the tp). when i press the switch i seem my led flashing but dosent stay on. i cannot receive any sounds from the board.

The power seem to go trough the board since when i put my meter on the positive and negative, i get a voltage reading. nothing seem to be fried, no smell of burn or black spots on the board.

Any help or hint would be appreciated

Thanks!

Hefty

[Kouri]

If you used  a US lithium-ion battery pack with an FX sound board without a 5V regulator, you very likely fried the board. The boards typically run at 3.6-5v, with some folks pushing them up to 6-6.5v. The lithium-ion pack would've put out 7.2-8.4v.

[Hefty]

oh, darn it. you know what could have fried on the board?

[Vyk]

The power seem to go trough the board since when i put my meter on the positive and negative, i get a voltage reading. nothing seem to be fried, no smell of burn or black spots on the board.

The amount of power you're dealing with would probably not leave any visible damage on the board, but it's well more than the board is designed for; I agree with Kouri that you probably fried the board.  I haven't seen a Force FX board, but the lower-end (basic or Ultimate FX) Hasbro boards basically have one important chip on them, some sensors, and a bunch of SMT resistors and capacitors.  Fried sensors shouldn't stop the board from firing up, and discrete resistors and capacitors are generally much more durable than the transistors inside the chip.  If your board has external power transistors for the blade and they fried, the result would probably be the opposite of what you're seeing--you'd have sound but no light.  Likewise, any dead external sound circuitry shouldn't affect the blade.  The fact that it's refusing to fire up aside from a brief blink is a bad sign.

The slight bit of encouragement I can give is that the symptoms you describe are similar to what happened with my basic Hasbro board when I broke a wire.  After I found that and repaired it, all was well.  I'd suggest going over the wiring very carefully to make sure that you don't have a broken wire.  Also check the board in case you accidentally cut a trace (unlikely--the boards are usually coated so that you'd have to exert some real effort--but if you think it's possible, look); if you did any soldering, look for possible bridged connections or board damage.  Make sure none of the factory solder joints seem bad (unlikely, but worth checking).  Take an extra-close look at any capacitors for any sign of damage.  (If you're lucky, they marked the SMT components with Rs or Cs; my cheap board has that, so I'd assume the Force FX does unless they were desperate for space.  On the other hand, many SMT capacitors are small enough that I doubt you could tell if they were blown from visual inspection.)

Once you've checked everything you can think of, hold the power wires on the original 3xAA battery pack's terminals (or any other power source that will deliver no more than 5V), cross your fingers, and hit the switch.  If it works, I would never try to run that board off of more than 5V; normally, I'd feel comfortable putting 6V through one of those boards, but with an already-stressed board, I'd stick as close to the 3.6-4.5V design spec as possible.  (Assuming your Force FX uses the same power that mine does.)

Good luck!

[Hefty]

The amount of power you're dealing with would probably not leave any visible damage on the board, but it's well more than the board is designed for; I agree with Kouri that you probably fried the board.  I haven't seen a Force FX board, but the lower-end (basic or Ultimate FX) Hasbro boards basically have one important chip on them, some sensors, and a bunch of SMT resistors and capacitors.  Fried sensors shouldn't stop the board from firing up, and discrete resistors and capacitors are generally much more durable than the transistors inside the chip.  If your board has external power transistors for the blade and they fried, the result would probably be the opposite of what you're seeing--you'd have sound but no light.  Likewise, any dead external sound circuitry shouldn't affect the blade.  The fact that it's refusing to fire up aside from a brief blink is a bad sign.

The slight bit of encouragement I can give is that the symptoms you describe are similar to what happened with my basic Hasbro board when I broke a wire.  After I found that and repaired it, all was well.  I'd suggest going over the wiring very carefully to make sure that you don't have a broken wire.  Also check the board in case you accidentally cut a trace (unlikely--the boards are usually coated so that you'd have to exert some real effort--but if you think it's possible, look); if you did any soldering, look for possible bridged connections or board damage.  Make sure none of the factory solder joints seem bad (unlikely, but worth checking).  Take an extra-close look at any capacitors for any sign of damage.  (If you're lucky, they marked the SMT components with Rs or Cs; my cheap board has that, so I'd assume the Force FX does unless they were desperate for space.  On the other hand, many SMT capacitors are small enough that I doubt you could tell if they were blown from visual inspection.)

Once you've checked everything you can think of, hold the power wires on the original 3xAA battery pack's terminals (or any other power source that will deliver no more than 5V), cross your fingers, and hit the switch.  If it works, I would never try to run that board off of more than 5V; normally, I'd feel comfortable putting 6V through one of those boards, but with an already-stressed board, I'd stick as close to the 3.6-4.5V design spec as possible.  (Assuming your Force FX uses the same power that mine does.)

Good luck!

Thanks for your answer.

i was going to rewire my board tonight to check it out. i really wish it could only be that :S

what does SMT stands for? i'm not too sure what i should look for.

also i'm the stupid one that put my lithium battery in and since everything worked i assume i was fine...

I have a big capacitor and my meter seemed to see the value of  it, meaning it should be fine. as for the chip, it is pretty much why i'm asking for help since i'm not too sure how it works since i get enough voltage on every pin.

anyway, i'll start with what you have and post my results

Thanks!

[Vyk]

what does SMT stands for? i'm not too sure what i should look for.

SMT is Surface Mount Technology.  It's widely used on modern electronics, being much more compact than older through-hole technology.  SMT resistors and capacitors are the little tiny rectangles that you'll see on the board; they are often arrayed in a line, but that's not a hard and fast rule.  There are also surface-mount transistors; these are slightly larger, marked with Q designations, and have three solder pads instead of two.  The larger capacitor you mentioned is probably a through-hole capacitor, with leads that penetrate the board and are soldered on the opposite side; it's a much stronger connection, but takes up more space, so it's now used mostly on large components.

I have a big capacitor and my meter seemed to see the value of  it, meaning it should be fine. as for the chip, it is pretty much why i'm asking for help since i'm not too sure how it works since i get enough voltage on every pin.

If you have a meter that measures capacitance, you can test the SMT capacitors.  Unlike a larger capacitor, they are usually not clearly marked for capacitance; so, basically, if they seem to be acting as capacitors at all, assume they're probably ok.  (And, of course, they'll be pretty low capacitance due to their small size.)

The problem with a chip is that voltage isn't the only concern; what matters is that everything is generating and passing the signals it needs to.  All you need is one transistor in there that will no longer switch and you're out of luck.  To know whether a chip is working correctly, you'd not only need to be able to measure the signal coming out (an oscilloscope should suffice here) but you'd also need to know what's supposed to be coming out.  If you aren't getting the right signal out, it's not something you can repair anyway; for that matter, it's usually not something you'd be able to narrow to a specific transistor even if you knew the internal design of the chip (which we don't).

My bet is that what's happening is that a transistor that is supposed to latch the power on was burned out by the over-voltage.  As a result, when you apply power, you get a brief flash as everything starts doing what it's supposed to, but the transistor doesn't actually hold the power on.  Now, I just realized something; I'd been assuming that such a transistor would be internal to the chip, but now I'm not 100% certain of that.  I found a picture of a Force FX Vader board (no idea if it's Signature or Black Series, or if there's a difference) and I noticed something interesting--there are a total of seven small SMT transistors (marked Q1-Q7).  Some of those must be for the blade segments; however, my Force FX only has five blade segments, and if yours is the same, there are two transistors "too many".  If one of those is what switches incoming power, and that is what has failed, you're down to the problem of having a single bad transistor rather than a bad chip; SMT is a nightmare to solder to (I'm nowhere near steady enough to do it), but it can be done, and you can get replacement transistors.  How to test them, though, is something I'm not sure of....  I know that many multimeters can test transistors, but that's for a larger, through-hole transistor, and for when they're separated from the circuit.


As I was writing this, one more thing occurred to me.  You probably already thought of this, but I'd feel really stupid if I didn't mention it and it turned out to be the problem.  Are you using the right kind of switch?  I saw that you "tested off the hilt my board with the switch and all" but I wasn't completely clear whether you meant you tested with the switch from the Force FX saber or the switch from the Ultrasaber.  If you were using a momentary switch where you needed a latching switch, you might get behavior similar to what you described--a flash and nothing else.  (I can't physically work the switch on my Force FX fast enough to know what a momentary switch might do to it; I'd think it would do a full power-up/power-down, but it might just flash like you described.  The light definitely starts slightly before the sound on mine.)

[Hefty]

SMT is Surface Mount Technology.  It's widely used on modern electronics, being much more compact than older through-hole technology.  SMT resistors and capacitors are the little tiny rectangles that you'll see on the board; they are often arrayed in a line, but that's not a hard and fast rule.  There are also surface-mount transistors; these are slightly larger, marked with Q designations, and have three solder pads instead of two.  The larger capacitor you mentioned is probably a through-hole capacitor, with leads that penetrate the board and are soldered on the opposite side; it's a much stronger connection, but takes up more space, so it's now used mostly on large components.
If you have a meter that measures capacitance, you can test the SMT capacitors.  Unlike a larger capacitor, they are usually not clearly marked for capacitance; so, basically, if they seem to be acting as capacitors at all, assume they're probably ok.  (And, of course, they'll be pretty low capacitance due to their small size.)

The problem with a chip is that voltage isn't the only concern; what matters is that everything is generating and passing the signals it needs to.  All you need is one transistor in there that will no longer switch and you're out of luck.  To know whether a chip is working correctly, you'd not only need to be able to measure the signal coming out (an oscilloscope should suffice here) but you'd also need to know what's supposed to be coming out.  If you aren't getting the right signal out, it's not something you can repair anyway; for that matter, it's usually not something you'd be able to narrow to a specific transistor even if you knew the internal design of the chip (which we don't).

My bet is that what's happening is that a transistor that is supposed to latch the power on was burned out by the over-voltage.  As a result, when you apply power, you get a brief flash as everything starts doing what it's supposed to, but the transistor doesn't actually hold the power on.  Now, I just realized something; I'd been assuming that such a transistor would be internal to the chip, but now I'm not 100% certain of that.  I found a picture of a Force FX Vader board (no idea if it's Signature or Black Series, or if there's a difference) and I noticed something interesting--there are a total of seven small SMT transistors (marked Q1-Q7).  Some of those must be for the blade segments; however, my Force FX only has five blade segments, and if yours is the same, there are two transistors "too many".  If one of those is what switches incoming power, and that is what has failed, you're down to the problem of having a single bad transistor rather than a bad chip; SMT is a nightmare to solder to (I'm nowhere near steady enough to do it), but it can be done, and you can get replacement transistors.  How to test them, though, is something I'm not sure of....  I know that many multimeters can test transistors, but that's for a larger, through-hole transistor, and for when they're separated from the circuit.


As I was writing this, one more thing occurred to me.  You probably already thought of this, but I'd feel really stupid if I didn't mention it and it turned out to be the problem.  Are you using the right kind of switch?  I saw that you "tested off the hilt my board with the switch and all" but I wasn't completely clear whether you meant you tested with the switch from the Force FX saber or the switch from the Ultrasaber.  If you were using a momentary switch where you needed a latching switch, you might get behavior similar to what you described--a flash and nothing else.  (I can't physically work the switch on my Force FX fast enough to know what a momentary switch might do to it; I'd think it would do a full power-up/power-down, but it might just flash like you described.  The light definitely starts slightly before the sound on mine.)

Hi  thanks for the big description here. i  will test those capacitor and check for the transistor. i will also try to find  those surface mount transistor if needed. also as for te switch i was using a latching every time, it was the same as my black series.

Thanks a lot it will give me something to think. i'm currently in the prossess of moving so i wont be able to do a complete check right away. i will update my post my my finding and troubleshooting in case of future use.

Again, thanks a lot!

[Vyk]

Good luck!  (Good luck with the move, too, for that matter. )