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DizzyKungFu
05-30-2008, 08:22 AM
I recently got ahold of one of the FX SW-616 kits (joe jedi construction) and gutted it for the soundcard to use in my MHS saber with a blue K2 Luxeon with two parallel 700mA BuckPucks.

I wired it up exactly like the diagram I found from Arm on Fire in his thread here: http://forums.thecustomsabershop.com/showthread.php?t=4252&page=2

And that was working great at first! Blade was nice and bright, sound was loud, I was very happy. But after turning it on and off a couple times to test it, something weird happened. At first I thought the sound had died completely, but then I realized that if I put my ear right up to the speaker, I could JUST BARELY still hear the sound effects. All the sounds are still correct... startup, hum, clash, shutdown. It's just extremely, extremely quiet now. Bizarre!

Nothing traumatic obviously happened to the sound board at the time this problem manifested. I didn't drop it. I'm only using 4 AAA alkalines at 6V, which is what Arm did and appears to be like others do with these kind of sound cards. I didn't see or smell any "magic smoke" or spot anything obviously damaged. And I assume that if I burned out the board, it would be totally dead, not just really quiet, right? I checked all the wires and all their solder connections, no problems there. I tried the speaker on another source and it worked fine. I tried fresh batteries. No change, it's still REALLY soft sound.

I don't THINK I did anything stupid, but maybe I did mess up somewhere and damage the board. But I can't for the life of me figure out how. Anyone ever hear of anything like this? Or simply have any thoughts on the matter?

ArkaiHalon
05-30-2008, 08:43 AM
I had this exact same problem with a vader sound card. Still have no Idea what happened.

Arm on Fire
05-30-2008, 09:33 AM
what are you using for a speaker?
Im also wondering if this problem is a product of pushing the voltage limits of a MR board by using 6v.
I had this happen when i tried to use a radio shack speaker, the speaker didnt take impact well ,but changed out the speaker and it's been fine ever since.

DizzyKungFu
05-30-2008, 09:58 AM
First of all; Arm, thanks for the great thread about building your "Fury" saber. The wiring diagram especially helped me out a lot! And I also stole your trick with taping and wiring the Buckpucks together. ;) Aren't you running 6v on your MR sound board, BTW? That's the impression I got from your posts.

To answer your question; I'm using one of the TCSS speakers. And I did think to try the board with another speaker (with no luck), and then tested both speakers on another source and they both worked fine. I'm pretty sure it's not a problem with the speaker... at least, directly.

Dark Navel
05-30-2008, 10:54 AM
This may sound really stupid, did you check your battery config?? Also try new batteries. Once the batts start to go it can cause crazy ^$^$ like this to happen. Not sure if your using a NIMH pack or a batt holder but make sure those connections are sound (no pun intended). I have seen the springs in batt packs come loose and cause issues.

DizzyKungFu
05-30-2008, 11:13 AM
This may sound really stupid, did you check your battery config?? Also try new batteries. Once the batts start to go it can cause crazy ^$^$ like this to happen. Not sure if your using a NIMH pack or a batt holder but make sure those connections are sound (no pun intended). I have seen the springs in batt packs come loose and cause issues.

Yeah, I thought of that. I'm using a battery holder with 4 AAA alkaline batteries, so I tried replacing both the batteries and the battery holder. To double-check, using a volt meter I tested the wires at the board's power input and at the ground, and it's reading that the board is indeed getting 6v. That was why I was originally afraid that I might have burned out the board, but 2 things about that don't add up 1) I'm pretty sure most people have claimed you can run safely a 616 board at 6v and 2) rather than just getting extremely quiet, wouldn't it just stop working all together?

But not a stupid suggestion at all! I posted this thread so I could get input, and maybe there is something I haven't thought of. Keep 'em coming!

Dark Navel
05-30-2008, 11:30 AM
Correct, 6V is the max for the MR boards including the MR-616. The only thing I can think of is maybe the board somehow hit the inside of the hilt and grounded/shorted something on the board?

The only true way of testing this out is to maybe but another 616 set? They're only 35 bucks right now. I'd hate to spend the $$ just to test it out but this way you'd be sure. If this isn't the problem and you get the same results well..then ya got yourself a 2nd soundcard for 35 bucks.;)

DizzyKungFu
05-30-2008, 11:48 AM
Correct, 6V is the max for the MR boards including the MR-616. The only thing I can think of is maybe the board somehow hit the inside of the hilt and grounded/shorted something on the board?

The only true way of testing this out is to maybe but another 616 set? They're only 35 bucks right now. I'd hate to spend the $$ just to test it out but this way you'd be sure. If this isn't the problem and you get the same results well..then ya got yourself a 2nd soundcard for 35 bucks.;)

Unfortunately, I got the last joe jedi kit in my local Radio Shack district. And they're going for like $60-$80 on eBay, plus $10-$20 shipping. The 616 is a decent enough sound card (certainly better than any Hasbro!), but that's a lot of money just for that, especially when you consider that the Ultrasound board was like $80 (when they were available) and that's also an LED driver!

fawnheart2000
05-30-2008, 02:56 PM
Ok first I think that you may have shorted out the speaker wires. basically blowing up the amplifier onboard the 616 joe jedi. I had this same problem.

secondly, check with your local radio shack, they are able to get some from other stores in their destict. Ask them how many are in their district. I've been able to get 9 616 joe jedi's from my local store at $35.

Novastar
05-30-2008, 02:58 PM
This problem smells very much like a capacitor that is loose or damaged, which could likely act as the sort of "audio amp".

This kind of thing actually happened to me back in 2007 for C4 with a CF v1.2. What I'd noticed is that this tantallum cap that Erv had attached to the audio chip was a bit loose on one of the leads. When it "broke away" a bit from that lead--the sound volume would drop to a whisper.

This is because the cap was SUPPOSED to be storing some energy FIRST... PRIOR to "shooting out" the audio signal. Since it couldn't, the signal was going right through, with no chance for some "good power".

I repaired it myself after speaking with Erv about things, and he told me where to look and what to look for. In retrospect, it made a ton of sense, and I immediately saw the "shakey" lead.

Anyhow... I'd *imagine* the SW-616 board could be quite similar... but... I don't know for certain.

DizzyKungFu
06-03-2008, 04:30 PM
Ok first I think that you may have shorted out the speaker wires. basically blowing up the amplifier onboard the 616 joe jedi. I had this same problem.

Hrmm... if you're correct about this, could I solve this by wiring in an amp on the speaker's lines? Like with this item from Radio Shack (it looks small enough): http://www.radioshack.com/product/index.jsp?productId=2062547

Admittedly, this is getting outside my electronics knowledge, but does anybody know if this would work? If so, how would I go about doing it?

Novastar
06-03-2008, 07:43 PM
I'm not 100% sure about the particular part you'd need... and... I think the chip there would need to be programmed to be "told what to do"... but...

...your IDEA is on the right track. :)

If you essentially substitute some kind of audio amp (I'd try a cap) of some sort... you could see how things turn out.

My GUESS is that... the WORST that could occur... is you could destroy the speaker if it ends up getting too much juice. But who cares--wire in a cheesy speaker that you don't care about for testing and there ya go.

I'm going to check with Erv on this... see if he's got some quick notes/suggestions.

erv
06-03-2008, 10:23 PM
Everything is in the boxes, so I can't get a look to the board itself, I don't have access to my MRs for the moment.
However, I thing that like most of the MR boards, the sound is generated from inside the resined chip on the board and you don't have any access. From what I remember on the previous MR boards is that the output amp is... a simple transistor mounted as a current amplifier. That's the part that burns generally. I suppose you could just replace this one, I think I did it before. I acutally took one of the transistor that was driving a led strip segment and swapped it.

DizzyKungFu
07-01-2008, 11:48 AM
Everything is in the boxes, so I can't get a look to the board itself, I don't have access to my MRs for the moment.
However, I thing that like most of the MR boards, the sound is generated from inside the resined chip on the board and you don't have any access. From what I remember on the previous MR boards is that the output amp is... a simple transistor mounted as a current amplifier. That's the part that burns generally. I suppose you could just replace this one, I think I did it before. I acutally took one of the transistor that was driving a led strip segment and swapped it.
Yes, that appears to be it. Thanks, Erv! While I wasn't able replace the one on the board itself because it's so tiny, I did manage to add a NPN transistor off the speaker out to restore the sound to a normal volume.

Darth_DevilGuy
07-01-2008, 04:34 PM
hmm, I'm having the same problem, what part specifically did you use and where in your circuit did you put it in? I'd like to know for myself but it'd be nice to have an answer on the boards too.

DizzyKungFu
07-01-2008, 05:51 PM
I used one of these: http://www.radioshack.com/product/index.jsp?productId=2062586 and wired it between the board's speaker out and the negative of the speaker. The base pin attaches to the board's speaker out (brown wire) and the collector pin attaches to the speaker's negative (usually a black wire, depending on your speaker). But a transistor has three pins so you need to wire the third pin, the emitter, to tap off the battery's negative line. I've heard that you generally have to "bias" a transistor by adding resistors, but I'm no electrical engineer and I couldn't tell you how to do that. However, this simple setup worked for me. :)