REPAIR GUIDE - TurboDuo: Sound Fix

[Duo_R]

Thanks, I have another Duo that I am swapping parts with until I figure out exactly what the issue is before I just blind start ordering parts since that can get expensive. This Duo has had every cap replaced, and I think I already did a swap with on of the M chips. This Duo is in great shape now besides ADPCM. I have this project on hold at the moment but will pick up pretty soon on it. Sadly I am doing no more mods once I ship Tron's Duo-R back but always here if anyone has a question or two. Just be patient because I won't be on the forums as much as I used to.

[Duo_R]

Override or anyone, do you know a good source for the M41464-10's? And damn these were a bitch to remove. I thought I had the technique all done then I lifted some tracing!!! It is fixeable but still going to be a pain in the ass.

[blueraven]

This part number for the RAM is M41464-12 not M41464-10, so I Assume it will not work, however; you may want to contact this eBay seller to see if he/she has stock.

http://tinyurl.com/mvdn6k

[Charlie]

"This part number for the RAM is M41464-12 not M41464-10"

The dash typically refers to the speed of the chip, if a 12 (slower @ 120ns) works, a 10 (faster @ 100ns) can be subitituted, but not the other way around.

Charlie

[incrediblehark]

So i replaced the pre and post op-amp caps in my duo mentioned by Dean and Duo-R (4 10uF 16V & 2 22uF 16V) and restored sound to my US duo, but the sound is sratchy, especially when cd and adpcm is playing. would this be another cap issue? there was mention of some more caps to replace (100, 1000, 470, and 220uF caps) near the amp. any ideas about the scratchiness of the audio? i dont really want to replace all of the caps, i dont feel experienced enough to do it.

[override]

So i replaced the pre and post op-amp caps in my duo mentioned by Dean and Duo-R (4 10uF 16V & 2 22uF 16V) and restored sound to my US duo, but the sound is sratchy, especially when cd and adpcm is playing. would this be another cap issue? there was mention of some more caps to replace (100, 1000, 470, and 220uF caps) near the amp. any ideas about the scratchiness of the audio? i dont really want to replace all of the caps, i dont feel experienced enough to do it.

There could be a number of reasons as to why the audio is scratchy, read here for the cd portion of things....

The other could simply be there are more caps that need to be replaced, aswell since you say you dont feel experienced enough to replace all the caps, you could simply have a bad connection to the new caps you replaced. You want to make sure the legs of the caps are pressed down all the way onto the pads that your resoldering to, you dont want them floating in the solder. Bend your caps legs like this ][ on bottom and when you have them mounted straighten them up then reheat one side at a time while applying light pressure on top of the cap to that side. If they sink any then they are "floating in the solder", once they wont go down anymore then they have made solid connection with the pads!

As for the Duo goes all together, I would say if your gonna replace a couple caps then you may aswell replace all of them, its not that hard of a task, if you take your time and be careful as to not lift any of the pads from the board, you can have it done in a day I'd say. You could always hire someone from the boards to do the work for you, myself included! Red Ghost I believe is doing cap replacements aswell. Im not positive on anyone else, but possibly chop5 and blueraven.

[Duo_R]

My experience (and I have seen similar results with others) is that scratchiness means a couple caps leaked on your board and causing intermittent grounding of different pins and causing shorts which creates the scratchiness sounds. The only fix I am aware of is a dishwash method. Do lots of research and reading about before you attempt, there are a couple threads on here on how to do it.

[skevenna73]

One of the kids in the lab had her Tacoma truck keyed today.  It runs all the way down the passenger side.  Does anyone have recommendations for a repair shop?

[NecroPhile]

One of the kids in the lab had her Tacoma truck keyed today.  It runs all the way down the passenger side.  Does anyone have recommendations for a repair shop?

May I suggest that you try dying in a fire?

[blueraven]

OK:

Got the Black PC Engine Duo to limp me to the end of Xanadu; now the real fun begins.

I did the sound cap replacement, the 4 10mf caps, and the 1 47.  I used the hi-temp caps just in case becase of the known problem with the heat synchs. It worked fine for about 2 minutes; full sound, redbook and huey music.

All of a sudden there is a heck of a lot of scratching during gameplay, crackling over the voices and occasionally cutting out. Re-booting to the main screen, the deafening scratching continued. I pulled the system apart, and cleaned it with 60/40 alcohol and a toothbrush. I -reset the laser to the origin position to see if that was the issue. Upon re-assembly, the static was really bad.

Here's the problem: there aren't any more leaky caps on the mainboard;

---

EDIT: There was a lot more wrong. I just finished a complete cap replacement, and the problems went away. At least 10 caps were leaking at the original time of this post. 4 22's, the 3.3 under the HOP-M3 (which needs replaced), 2 100's, 2 4.7's and 2 47's. (all microfarads). A good scrubbing with 70% alcohol and a toothbrush took care of the excess electrolytic fluid. Photos posted on the PCE Duo complete cap replacement thread;

[King_Vidiot]

I sent my Duo away to get a region mod and the sound fix.  The region mod works but my sound (just the music, not the sound effects) still cuts out when playing certain CD-based games (Dracula X, Valis, etc). 

Could someone point me to the best post(s) that address this problem?  I was thinking of just opening mine up, seeing what the guy did who "fixed" my sound to see if I can spot anything he skipped or didnt do.

thanks

[D-Lite]

I sent my Duo away to get a region mod and the sound fix.  The region mod works but my sound (just the music, not the sound effects) still cuts out when playing certain CD-based games (Dracula X, Valis, etc). 

Could someone point me to the best post(s) that address this problem?  I was thinking of just opening mine up, seeing what the guy did who "fixed" my sound to see if I can spot anything he skipped or didnt do.

thanks

Do you know what the person did to fix the sound?  Unless it was a full cap replacement you can assume that's likely the problem.  I'm not going to ask you to post the person's name here, but I would send it back and ask for it to be done again since you paid for the work.  Well, providing you paid for a full, guaranteed repair.  For me, when I do one of these (only done it once for someone else so far, but have done many for consoles I have on hand), I thoroughly check the system performance before sending it out and asking for payment.  There's a chance it's the pots too, if they weren't adjusted.

[King_Vidiot]

I assume what he did was a full cap replacement, I guess what I'm asking is once I open up the system, how can I verify this or not?  Maybe he missed a cap or two?  And if it's the pots, how do I test or adjust?

[Charlie]

==>And if it's the pots, how do I test or adjust?<<=

SEARCH function may help!

"5 silver pots on the Turbo Duo pcb"

Charlie

[King_Vidiot]

...or you could have saved your keystrokes and just posted the link

[Charlie]

Nah, then I would have had to find it myself!  Less work this way.

Good luck

Charlie

[Duo_R]

D-lite,

any thoughts to the lack of ADPCM sounds? I got a full cap replaced Duo everything works except ADPCM sounds. Very strange, no scratchiness anymore just 0 volume for ADPCM. Alot of good ideas shared on here but wondering if u ever tackled that one yourself.

Duo

I sent my Duo away to get a region mod and the sound fix.  The region mod works but my sound (just the music, not the sound effects) still cuts out when playing certain CD-based games (Dracula X, Valis, etc). 

Could someone point me to the best post(s) that address this problem?  I was thinking of just opening mine up, seeing what the guy did who "fixed" my sound to see if I can spot anything he skipped or didnt do.

thanks

Do you know what the person did to fix the sound?  Unless it was a full cap replacement you can assume that's likely the problem.  I'm not going to ask you to post the person's name here, but I would send it back and ask for it to be done again since you paid for the work.  Well, providing you paid for a full, guaranteed repair.  For me, when I do one of these (only done it once for someone else so far, but have done many for consoles I have on hand), I thoroughly check the system performance before sending it out and asking for payment.  There's a chance it's the pots too, if they weren't adjusted.

[SNKNostalgia]

I wonder if the Oki MSM5205 ADPCM chips tend to fry out on Duo systems? I mean it is hard to imagine what else can go wrong after replacing all the caps. The only other cause I can think of is bad traces with corrosion from the leaking caps before replacement. The other problem could be no power getting to the to the Oki chip, or the CD control board not sending the data to it.

[D-Lite]

D-lite,

any thoughts to the lack of ADPCM sounds? I got a full cap replaced Duo everything works except ADPCM sounds. Very strange, no scratchiness anymore just 0 volume for ADPCM. Alot of good ideas shared on here but wondering if u ever tackled that one yourself.

Duo

I sent my Duo away to get a region mod and the sound fix.  The region mod works but my sound (just the music, not the sound effects) still cuts out when playing certain CD-based games (Dracula X, Valis, etc). 

Could someone point me to the best post(s) that address this problem?  I was thinking of just opening mine up, seeing what the guy did who "fixed" my sound to see if I can spot anything he skipped or didnt do.

thanks

Do you know what the person did to fix the sound?  Unless it was a full cap replacement you can assume that's likely the problem.  I'm not going to ask you to post the person's name here, but I would send it back and ask for it to be done again since you paid for the work.  Well, providing you paid for a full, guaranteed repair.  For me, when I do one of these (only done it once for someone else so far, but have done many for consoles I have on hand), I thoroughly check the system performance before sending it out and asking for payment.  There's a chance it's the pots too, if they weren't adjusted.

ONCE.  And replacing the 5205 worked perfectly for it.  Again, only had this happen once out of dozens of systems and that fixed it, as SNKNost said.  So odd to have an IC fail like that, but was exactly the cause.

[Duo_R]

D-lite - unfortunately 5205 swap didn't change anything on this Duo. I have replaced some other parts, and I am still trying to find sources for some of the other IC's. It would be awesome if someone had a full part reference for all the IC's on compatible replacements and source.

I did a swap from a US Duo to a JP Duo with the M5205 chip. Both systems retained the same behavior (US Duo no ADPCM, JP Duo has ADPCM but fading audio). The JP Duo hasn't had a cap swap yet so that is why the fading audio is there. As I stated both systems behaved exactly the same. So I am beginning to suspect another part. What about the other IC's near this area? I know one of them is the opamp, what os the IC between Opamp and the M5205 chip? It is directly above the voltage regulators, long skinny IC.

[override]

Duo_R your still messing with that duo?

Whatever happen to the two chips I sent you?

[Duo_R]

Hey man sorry totally slacking on getting those back to you. Just send you a PM, reply with your addy and they will be on their way. Yeah unfortunately swapping the IC's didn't change anything, so at least it ruled those out for me. I got more IC's to swap up but not much time. More seeing if others have fixed this issue before I go mad and replace every damn part... LOL

-Duo

Duo_R your still messing with that duo?

Whatever happen to the two chips I sent you?

[unclebugspayton]

So if i have scratchy sound i should change the post op amp caps and pre amp?

[blueraven]

I'd recommend changing all the caps around the heat synch's, but you may be able to get away with just the sound caps. I wasn't so lucky. I had the same problem; scratchy sound, and it went to fade out after a month or so. Make sure you clean up all of the excess flux and grime around the sound chip; this was causing the problem on one incredibly dirty unit from a turbo-smokers house.

I've just finished 2 complete cap replacements on Black PCE Duo's; I'm running the green NTK hi-temp caps for the sound area, as they can withstand hours and hours of extended gameplay.

[unclebugspayton]

What can i use to clean the excess flux and grime around the sound chip?

[ogre]

I just use regular old cheap rubbing alcohol 90%. You can get other flux cleaners but I have found them to be no more effective.

[kattare]

Alcohol and Q-Tips for me.

[agt_dale_cooper]

For ADCPM audio (sourced by U502), come out mono through cap c652 to passive filter (uses c623), to one-half of U503 amp  , out U503 (cap 653) through passive filter (uses c621) to other-half of U503, into U504 audio gate (both channels), continue as above.

Dear God, I'm working on ANOTHER of these failed frelling Duos.  Got one as parts off some guy on the TurboList, but has no ADPCM, even after recapping most of the board in that vicinity.
Board does play Redbook, does play in-game.
ADPCM test vehicle is "Gate/Bonk 1/Bonk 2" disc...when you first boot it, Bonk comes out in the spotlight and TALKS....you see the quote on screen, but there is "Bonk-ese" that plays in the background when the quotes come on the screen:
Screen text "Me Bonk" - ADPCM plays "Ooga Bonk"
Screen text "You Player" - ADPCM plays "Dabba Dooba"
Screen text "We Play" - ADPCM plays "Ooga Mooga"
[Apologies to Bonk if I've spelled his words incorrectly   ]

Assuming the recap was successful, how do we test the surface mount components mentioned by Charlie?
I'm looking specifically at:
C652 (bottom of board, surface mount)
C623 ("""")
C621 (top of board, surface mount)
I'm looking to test ALL caps before resorting to replacement of the M5205.

Speaking of, anybody have intelligent solutions for doing this?  Chip lifters or something?  A really tiny spatula?  What's proper methodology for doing something like this?

[Duo_R]

ok I am beginning to suspect the BU4053BF chip for my ADPCM problems and I think I found a more current replacement:

BU4053BCF

http://pdf1.alldatasheet.com/datasheet-pdf/view/36348/ROHM/BU4053BCF.html


Does anyone know how to apply the test circuits listed in the PDF? Is it possible that we can run these tests to determine if the stock chip is functioning properly?

[Charlie]

There are two "easy" ways to test this chip, without even unsoldering it.  But "easy" doesn't mean simple or practical.

This chip is simply an electronic switch.  All it does is connect some input signal to an output line.  But, it does that under strict control.  You can either:
1. Monitor those control signals, use the data sheet to determine what the chip should do to the output line, then check if it has, in fact, done that.
2. Temporarily make the switch connections yourself; that is, "short" the input to the output.

Method #1 is dependent upon the system manipulating the controls signals, which means you have no direct control over them.  The difficulty here is that you are at the mercy of whatever the configuration the game controls, with, of course, any exceptions that can be configured with some kind of operator options.  Basically, you are saying "ok, with the controls inputs set as X (which is outside my control), the signal I see on Y should come out Z.  Let me check that".  You'll need to use the data sheet to derermine X, Y and Z.  Again, you have no control over X, and therefore no way to positively guarantee you have checked all inputs/output, since all possible combinations may not necessarily be functional for that game.  By the way, do you have appropriate test equipment?  An oscilloscope is ideal, but generally not part of your gaming system.
A VOM (multimeter) may work, if it is sensitive enough to detect very small sound signals.

Method #2 is much easier, and only requires a short piece of jumper wire.  However, it is much more prone to error, which can equate to destroying the chip.  In this method, you basically make the electronic connection yourself.  If the sound suddenly starts working, you now have a clue (Note: if this DOES work, it DOES NOT follow that the chip is bad.....this is only another clue).  The problem with this is that you don't know what input signal is supposed to connect with what output signal.  Generally, this is not a problem in terms of hurting the chip...just make very, very sure you are connecting inputs to outputs, and not to power or ground.  Also, you must realize that you are likely to get strange sounds, because you will be connecting a signal that the game has turned off, and forced that signal on.  However, you are not necessarily looking for correct sound in the first place...you are testing to see whether there is any sound at all.

Charlie

[Duo_R]

what pins are jumped for method 2?

[agt_dale_cooper]

FINALLY got some love out of my PAIR of ailing PCE Duos...
Had one (mentioned earlier in this thread, months ago) that's been sitting around doing nothing.....ADPCM worked, but no Redbook.
Bought another off a dude on the TurboList as parts.....Redbook works, but no ADPCM.

Pulled the M5205 off both units, switched out their respective M5205s.  Used a socket to facilitate easier testing in the future:  Radio Shack 276-1992, $0.48.  Soldered the socket down, stuck the working 5205 into it, and Bonk talks.  NICE!!!

Methodology/tools used:
Radio Shack 45 watt desoldering iron/bulb, P/N 64-2060:  http://www.radioshack.com/product/index.jsp?productId=2062731
Desoldered all 18 pins, sucking solder up with above product.  This thing is HOT, don't let it sit on your chip's leg while you answer the phone.  Excessive heat applied directly to any chip will fry it's little guts.

Once all 18 pins were reasonably clean, plugged in the Weller WM120 12W:  http://www.frys.com/product/64252?site=sr:SEARCH:MAIN_RSLT_PG
Using MP131 tip:  http://www.frys.com/product/64311?site=sr:SEARCH:MAIN_RSLT_PG (comes with the unit above)

Grabbed the chip (still stuck in place at this point) with these black tweezer-looking things, Radio Shack 276-1581:  http://www.radioshack.com/product/index.jsp?productId=2103244
Suprisingly handy....allows you to maintain pretty much consistent withdrawal pressure on the chip.

Flipped motherboard over, heated individual pins that appeared to still be holding on to the board, chip came off easily.

Rinse and repeat for donor board.

Install socket mentioned above, RS 276-1992....the divot in the end of it goes towards the heatsinks.  Installing this socket also keeps you from overheating the chip itself while soldering (you're soldering socket instead directly on chip), provided you didn't already with the desoldering iron above.  Use the WM120/MP131 combo to solder it in place...stick the thing onto the board, solder.  Heat each leg protruding through the board, touch with solder, should be sufficient if you're connecting PCB pads and socket legs.

Insert M5205 into socket, divot in end of chip goes towards the heatsinks.  The chip should press down into the socket...if it doesn't, clean your chip legs for ease of insertion.  NO NEED TO SOLDER CHIP INTO PLACE.

Reinstall board into machine, test.  If Bonk talks, you're stoked.  Sell it quickly.   

Fortunately for me, this simple switch worked....now it's onto installing the region switch...urgh.  [Kynar 30 gauge + Radio Shack 276-1570 + 82MS2R3 slide switch = bliss...]

Still looking for commentary on how to test the surface-mount caps mentioned earlier on this page......can't test them in-circuit, pulling them off the board is the only way...perhaps if Charlie can come up with recommended values for these guys in the ADPCM circuit, this can help Duo_R with his 'already replaced the chip' dilemma.

[agt_dale_cooper]

Let it be it known today, May 31, 2010, "Memorial Day" here in the United States of America, that PC Engine Duo serial number 1X146474A gave it's life so that others of it's kind might live.
On a day where we all remember and honor our dead, so shall 1X146474A be remembered and honored.
 

[Duo_R]

Dale did the Duo get sacrificed in vain?

[Charlie]

==>"what pins are jumped for method 2? "<<=

Answer already in my previous post:
==>"You'll need to use the data sheet to derermine X, Y and Z"<==

(And, yes, I know I spelled "determine" incorrectly)

You yourself already posted the source for the previously mentioned data sheet.  It is infintely more practical to look at that, than it is to type out four paragraphs of text to describe the block diagrams and flowcharts.

----------------------------------------------------
==>"perhaps if Charlie can come up with recommended values for these guys in the ADPCM circuit"<==

Gotta dig through the notes, see what I can do about getting ANY data about the ADPCM circuit.  However, I suspect that there is a significant amount of stuff in that entire section.....if you can narrow down to anything specific you need, that would help. 

Back later,

Charlie

[Charlie]

Back here, for a quickie.
Checked through a few of the previous posts we have had about this problem.  Do a search for "U503" and you will get a lot of data buried in two different threads.  True, that is not ALL the data.  However, the data that IS posted is the most significant for troubleshooting; what is missing is stuff that has a low probability (but not zero!) of causing the problem.  If you have tried all the stuff already listed in those posts, let me know and we'll go further.  However, be aware that, if we have to dig deeper, it means we need more minute details and will probably get complex to describe and more frustrating to analyze.  (Unless you have an electronics lab, in which case you probably already fixed it!!!)

Let's hope the failure is on the analog side, and not the digital side!

Charlie

[agt_dale_cooper]

For ADCPM audio (sourced by U502), come out mono through cap c652 to passive filter (uses c623), to one-half of U503 amp  , out U503 (cap 653) through passive filter (uses c621) to other-half of U503, into U504 audio gate (both channels), continue as above.

Assuming the recap was successful, how do we test the surface mount components mentioned by Charlie?
I'm looking specifically at:
C652 (bottom of board, surface mount)
C623 ("""")
C621 (top of board, surface mount)

C652, C623 and C621 are all part of the circuit described by Charlie in first quote.  These are SURFACE MOUNT, and in order to test them, you need to remove them at least partially from the board.  As I don't know specifically what the frell they are, I was looking for Charlie to provide insight:
1)  What they are (diodes, capacitors, etc.)
2)  Possible part numbers if replacement is needed
3)  Test values for working unit, or multimeter SETTINGS to test.  Have multimeter, will test, once I figure out how.  Will post values for others' reference, might be helpful in analyzing Duo_R's "already replaced the M5205" problem.  If one of these surface mount cats have blown, would presumably account for unit's behavior.

Duo_R, I can't locate "BU4053BF".....give me an approximate physical location, I'll pull mine from my leftover parts (1X146474A from above) and send to you if needed.  Bear in mind, however, that the ADPCM on this unit did NOT work.....yours for the taking if you feel like testing with it, though.  Board is parts, and I'm gonna toss it soon.

[Charlie]

C652 is 0.1 uf (microfarads)
C623 is 0.22 uf (microfarads)
C653 is 10uf, 16V
C621 is.....I have no notes on that one, nor C622.  (But see end of post)

First question: is the capacitor in question a series path from point A to point B, or a bypass path from point A to ground?  For the above:
C652 is series, point A to point B
C623 is bypass, point A to ground
C653 is series, point A to point B
C621 is bypass, point A to ground
C622 is series, point A to point B
 
Bypass caps usually mean the cap can be temporarily removed; it will allow the circuit to work, but not necessarily properly or the most efficiently.  However, if that cap is preventing the proper function completely, removing it and finding that you now get a partial circuit function is certainly a key indicator!

Series cap usually mean the cap absolutely must work for the circuit to work.  You want to check these caps after you have eliminated any bypass caps as the problem.  Reasons for that is, the series cap needs a bit more in-depth analysis.  So, do the easier bypass caps first.  In the case of the ASPCM circuit, both C623 and C621 can be removed for this analysis.  Keep track of which is which, and remember to reinstall (or replace) them later!!!!

So, the next step is the series caps, right?  Yes,.....but there is a little bonus for us in this circuit; C622 is used as feedback, which means the circuit can probably operate without it!  So go ahead and remove it, too.  Again, remember to reinstall/replace.

Since you have (presumably) removed the bypass caps, do a little testing...
Start with the simplest analysis first: A capacitor is going to be shorted or open.  You want to check for both of these errors; if you can eliminate both of these possibilities, then assume it's good (NOT a guarantee, but a reasonable bet for first level troubleshooting).

[What about testing for a "leaky" cap?  That's why I said "simplest analysis first".  Determining if a cap is leaky can require a bit more work (unless of course you see electrolyte all over the board!), and the short/open checks can help you toward this.]

Now what?......
You want to check if the cap is shorted or open.  You need to apply both tests, as you can get an ambiguous result and will need both data points to eliminate the ambiguity.   Make a chart for each cap, check:
1. With power off, resistance from first pin to ground
2. With power off, resistance from second pin to ground
3. With power on and no ADPCM audio active, DC voltage on first pin relative to ground
4. With power on  and no ADPCM audio active, DC voltage on second pin relative to ground
5. With power on and ADPCM audio active, AC voltage on first pin relative to ground
6. With power on and ADPCM audio active, AC voltage on second pin relative to ground
Note that, for 5 & 6, you may be looking for a few hundredths of a volt, so you need to use the most sensitive scale on the meter, and make sure you are NOT getting a false reading caused by any nearby electric/electronic interference.

Now you need to use the tool between your ears:

If the cap is shorted, then the DC voltage will be the same on both it's pins.  Of course, be careful that the cap doesn't, by coincidence, connect two points that happen to actually have the same DC voltage.   Usually, however, the whole point of the cap is specifically intended to keep the two voltages separate, so, if the DC voltages are different, assume the cap is not shorted. 
 
If the cap is open, you will certainly have different DC voltages on it's pins (again, unless the circuits in use happen to have the same voltage). But a good cap will have this too, so check the AC voltages.  You should have the same on both sides; that's the caps job, to get the signal from point A to point B.  We will assume that point B is, itself, not the problem.  If it looks like the cap IS open, it is safe to temporarily connect a second, new cap into the circuit...without having to remove the original, suspect cap.  Just be sure to observe polarity, if any.

Shortcut:
In the case of the ADPCM circuit, U503 is used as a two-stage amplifier filter.  This means that pin 1 has a much more powerful ADCPM signal than U502 or any parts in-between. So, you could try just measuring the AC voltage on pin 1, and compare the value of ADCPM audio off with the value of ADCPM on.  But I guess you have done that, otherwise you would not be concentrating on the actual capacitors.  However, as we have shown, C652 (and C653, which you did not mention) are the only two critical caps in this circuit.  And if you do the simple short test (same DC voltage on both pins), and the simple open test (connect a second known-good capacitor across them), testing this circuit is easy.

As for C621 and C622:
I mentioned that C622 could PROBABLY be removed and the circuit could still work.  This is because both of these caps are used as "filter elements" in an "active filter".  This is a fancy way of saying they help "shape" the sound, kind of like an equalizer is used for audio systems.  Of course, this equalizer only has one setting.  But, without those caps, this equalizer circuit MAY have characteristics that, while still functioning properly, act like it isn't.  So removing C622 if it is good (but you don't know that) has a small chance of actually making things appear worse. 

As for the values, that depends upon what effect the equalizer is supposed to have; that is, what the audio is actually supposed to sound like.  For test purposes, I would remove them both until you have (probably poorly) working audio, then reinstall them one at a time as a test.

Charlie

[chany60126]

Hey Guys,

I could really use your help. This is probably a stupid question, but do you need a 4.5 MM gamebit to open up a US Duo?? I used the one recommended on page 4 of this thread from

http://www.ncsxshop.com/cgi-bin/shop/NUS-45MM.html

and it won't fit on the screw!! Did I purchase the wrong one??

[agt_dale_cooper]

4.5mm gamebit is standard for the USA Turbo Duo.  Top of screw is CONVEX.
Torx Security T10 is standard for the Japanese Turbo Duo.  Top of screw is concave.

If your 4.5mm doesn't fit, perhaps they sent a 3.8mm by mistake.
Got a NES or SNES cart kicking around the house?  They're put together with either flat head (NES) or 3.8mm (NES/SNES) screws.
Got a Genesis cart around the house?  They're put together with either philips or 4.5mm screws.

Check your screw bit against the NES/SNES/Genesis carts to determine it's size.  If this doesn't work, take a GOOD picture of your screw, and we'll collectively figure it out for you.

[chany60126]

4.5mm gamebit is standard for the USA Turbo Duo.  Top of screw is CONVEX.
Torx Security T10 is standard for the Japanese Turbo Duo.  Top of screw is concave.

If your 4.5mm doesn't fit, perhaps they sent a 3.8mm by mistake.
Got a NES or SNES cart kicking around the house?  They're put together with either flat head (NES) or 3.8mm (NES/SNES) screws.
Got a Genesis cart around the house?  They're put together with either Phillips or 4.5mm screws.

Check your screw bit against the NES/SNES/Genesis carts to determine it's size.  If this doesn't work, take a GOOD picture of your screw, and we'll collectively figure it out for you.

Well, I am pretty sure that it's not a 3.8 MM security bit as the bit can't even fit inside the hole where screw is for SNES games. I tried it on a couple of Genesis games and it can't grip it. I am not sure if this company gave me a generic gamebit or what. The grooves on the bit don't look wide enough to grip the screw even though it fits the hole.

This is the best pic I could take with my cam:

[agt_dale_cooper]

From the picture, appears you have the correct style bit.
DON'T understand it's ability to open a Genesis game.
Are the screws in the Genesis the same as the screws in your Duo?
Got anybody local to you that handles such matters?  Try Craigslist, if present for your vicinity.
Don't know what to tell you, unfortunately...strange.

[chany60126]

From the picture, appears you have the correct style bit.
DON'T understand it's ability to open a Genesis game.
Are the screws in the Genesis the same as the screws in your Duo?
Got anybody local to you that handles such matters?  Try Craigslist, if present for your vicinity.
Don't know what to tell you, unfortunately...strange.

I went to my local Play N Trade since they can repair anything, even retro. The repairs guy confirmed that it was definitely the wrong bit since it is not keyed in properly compared to the screws on the Duo. He even tried to open up an n64 system, but no dice. Too bad he couldn't find his gamebit. The screws on my Duo are the same ones as the Genesis carts. What a headache... Where did you buy your gamebit from??

[DragonmasterDan]

From the picture, appears you have the correct style bit.
DON'T understand it's ability to open a Genesis game.
Are the screws in the Genesis the same as the screws in your Duo?
Got anybody local to you that handles such matters?  Try Craigslist, if present for your vicinity.
Don't know what to tell you, unfortunately...strange.

I went to my local Play N Trade since they can repair anything, even retro. The repairs guy confirmed that it was definitely the wrong bit since it is not keyed in properly compared to the screws on the Duo. He even tried to open up an n64 system, but no dice. Too bad he couldn't find his gamebit. The screws on my Duo are the same ones as the Genesis carts. What a headache... Where did you buy your gamebit from??

Play N Trade's generally have trouble doing repairs for systems they either don't have an outside vendor to repair or are not in their guidebook.

Added in edit: After consulting a friend of mine who was employed at one. Most of what they do internally at his store is simple NES 72 pin connector swaps. Everything else they were sending out to a vendor. It's on a franchise by franchise basis apparently.

I'm guessing you went to the one next to the movie theatre in Downtown Elmhurst?

In any event, I bought the correct gamebit from Nintendo Repair Shop online.

[chany60126]

From the picture, appears you have the correct style bit.
DON'T understand it's ability to open a Genesis game.
Are the screws in the Genesis the same as the screws in your Duo?
Got anybody local to you that handles such matters?  Try Craigslist, if present for your vicinity.
Don't know what to tell you, unfortunately...strange.

I went to my local Play N Trade since they can repair anything, even retro. The repairs guy confirmed that it was definitely the wrong bit since it is not keyed in properly compared to the screws on the Duo. He even tried to open up an n64 system, but no dice. Too bad he couldn't find his gamebit. The screws on my Duo are the same ones as the Genesis carts. What a headache... Where did you buy your gamebit from??

Play N Trade's generally have trouble doing repairs for systems they either don't have an outside vendor to repair or are not in their guidebook.

Added in edit: After consulting a friend of mine who was employed at one. Most of what they do internally at his store is simple NES 72 pin connector swaps. Everything else they were sending out to a vendor. It's on a franchise by franchise basis apparently.

I'm guessing you went to the one next to the movie theatre in Downtown Elmhurst?

In any event, I bought the correct gamebit from Nintendo Repair Shop online.

Yep, I went to Play N Trade in Elmhurst, it's only a half mile from my house. The guy who does repairs, Steve, has worked with gamebits before. He seems to know what he is talkin about. He is excellent at soldering stuff as he has fixed many RROD for 360s. I will probably seek his advice on how to solder since I have never done that before. The guys there are awesome.

I will look into the nintendo repair site after I email the peops (ncsx.com) who sold me the wrong gamebit. I think.
There is a label on the baggie where gamebit came that says 22-1150. Did your gamebit have a similar description?

Thanks,

[DragonmasterDan]

From the picture, appears you have the correct style bit.
DON'T understand it's ability to open a Genesis game.
Are the screws in the Genesis the same as the screws in your Duo?
Got anybody local to you that handles such matters?  Try Craigslist, if present for your vicinity.
Don't know what to tell you, unfortunately...strange.

I went to my local Play N Trade since they can repair anything, even retro. The repairs guy confirmed that it was definitely the wrong bit since it is not keyed in properly compared to the screws on the Duo. He even tried to open up an n64 system, but no dice. Too bad he couldn't find his gamebit. The screws on my Duo are the same ones as the Genesis carts. What a headache... Where did you buy your gamebit from??

Play N Trade's generally have trouble doing repairs for systems they either don't have an outside vendor to repair or are not in their guidebook.

Added in edit: After consulting a friend of mine who was employed at one. Most of what they do internally at his store is simple NES 72 pin connector swaps. Everything else they were sending out to a vendor. It's on a franchise by franchise basis apparently.

I'm guessing you went to the one next to the movie theatre in Downtown Elmhurst?

In any event, I bought the correct gamebit from Nintendo Repair Shop online.

Yep, I went to Play N Trade in Elmhurst, it's only a half mile from my house. The guy who does repairs, Steve, has worked with gamebits before. He seems to know what he is talkin about. He is excellent at soldering stuff as he has fixed many RROD for 360s. I will probably seek his advice on how to solder since I have never done that before. The guys there are awesome.

I will look into the nintendo repair site after I email the peops (ncsx.com) who sold me the wrong gamebit. I think.
There is a label on the baggie where gamebit came that says 22-1150. Did your gamebit have a similar description?

Thanks,

I've bought from NCS many many many times. Not usually had a problem. My gamebit (I bought two different ones from Nintendo repair shop at the time) literally arrived in a regular envelop in a tiny baggie with an invoice.

Added in edit:As far as that play N trade goes. I like the people there. I never find much product I want there however. Whereas I've had better luck finding retro stuff I want at some of the other Play N trades in the area. Cool people there though. I've been there 20-30 times, some of the employees recognize me there by now.

The downside to that Play N Trade is the location. Living only a half a mile from there is one of the few ways to actually get to that play n trade since downtown Elmhurst has practically no parking. I usually park all the way down by Hamburger Heaven and just walk whenever I go to that one.

[chany60126]

From the picture, appears you have the correct style bit.
DON'T understand it's ability to open a Genesis game.
Are the screws in the Genesis the same as the screws in your Duo?
Got anybody local to you that handles such matters?  Try Craigslist, if present for your vicinity.
Don't know what to tell you, unfortunately...strange.

I went to my local Play N Trade since they can repair anything, even retro. The repairs guy confirmed that it was definitely the wrong bit since it is not keyed in properly compared to the screws on the Duo. He even tried to open up an n64 system, but no dice. Too bad he couldn't find his gamebit. The screws on my Duo are the same ones as the Genesis carts. What a headache... Where did you buy your gamebit from??

Play N Trade's generally have trouble doing repairs for systems they either don't have an outside vendor to repair or are not in their guidebook.

Added in edit: After consulting a friend of mine who was employed at one. Most of what they do internally at his store is simple NES 72 pin connector swaps. Everything else they were sending out to a vendor. It's on a franchise by franchise basis apparently.

I'm guessing you went to the one next to the movie theatre in Downtown Elmhurst?

In any event, I bought the correct gamebit from Nintendo Repair Shop online.

Yep, I went to Play N Trade in Elmhurst, it's only a half mile from my house. The guy who does repairs, Steve, has worked with gamebits before. He seems to know what he is talkin about. He is excellent at soldering stuff as he has fixed many RROD for 360s. I will probably seek his advice on how to solder since I have never done that before. The guys there are awesome.

I will look into the nintendo repair site after I email the peops (ncsx.com) who sold me the wrong gamebit. I think.
There is a label on the baggie where gamebit came that says 22-1150. Did your gamebit have a similar description?

Thanks,

I've bought from NCS many many many times. Not usually had a problem. My gamebit (I bought two different ones from Nintendo repair shop at the time) literally arrived in a regular envelop in a tiny baggie with an invoice.

Added in edit:As far as that play N trade goes. I like the people there. I never find much product I want there however. Whereas I've had better luck finding retro stuff I want at some of the other Play N trades in the area. Cool people there though. I've been there 20-30 times, some of the employees recognize me there by now.

The downside to that Play N Trade is the location. Living only a half a mile from there is one of the few ways to actually get to that play n trade since downtown Elmhurst has practically no parking. I usually park all the way down by Hamburger Heaven and just walk whenever I go to that one.

The Elmhurst Play N Trade is pretty good. They get some good stuff from time to time. I go there at least once a week since bank is right across the street. I am astonished to hear that you park all the way by Hamburger Heaven. You should park at the Chase/Walgreens parking lot right in front of the store. Chill out at Walgreens for a bit just to play it safe. I have found some pretty nice finds at Elmhurst PNT. In fact, I picked up Splatterhouse 2 and 3 for a combined $20 about a month and a half ago. The only other PNT i've been to is in bloomingdale right in front of Stratford mall, but I believe that one closed. Which ones do you like??

On a side note, I was surprised to see that the Microcenter carries 4.5 gamebits!! They are Out of stock but I'll visit the one in westmont and see if they'll order one for me.

http://www.microcenter.com/single_product_results.phtml?product_id=0335650

[DragonmasterDan]

From the picture, appears you have the correct style bit.
DON'T understand it's ability to open a Genesis game.
Are the screws in the Genesis the same as the screws in your Duo?
Got anybody local to you that handles such matters?  Try Craigslist, if present for your vicinity.
Don't know what to tell you, unfortunately...strange.

I went to my local Play N Trade since they can repair anything, even retro. The repairs guy confirmed that it was definitely the wrong bit since it is not keyed in properly compared to the screws on the Duo. He even tried to open up an n64 system, but no dice. Too bad he couldn't find his gamebit. The screws on my Duo are the same ones as the Genesis carts. What a headache... Where did you buy your gamebit from??

Play N Trade's generally have trouble doing repairs for systems they either don't have an outside vendor to repair or are not in their guidebook.

Added in edit: After consulting a friend of mine who was employed at one. Most of what they do internally at his store is simple NES 72 pin connector swaps. Everything else they were sending out to a vendor. It's on a franchise by franchise basis apparently.

I'm guessing you went to the one next to the movie theatre in Downtown Elmhurst?

In any event, I bought the correct gamebit from Nintendo Repair Shop online.

Yep, I went to Play N Trade in Elmhurst, it's only a half mile from my house. The guy who does repairs, Steve, has worked with gamebits before. He seems to know what he is talkin about. He is excellent at soldering stuff as he has fixed many RROD for 360s. I will probably seek his advice on how to solder since I have never done that before. The guys there are awesome.

I will look into the nintendo repair site after I email the peops (ncsx.com) who sold me the wrong gamebit. I think.
There is a label on the baggie where gamebit came that says 22-1150. Did your gamebit have a similar description?

Thanks,

I've bought from NCS many many many times. Not usually had a problem. My gamebit (I bought two different ones from Nintendo repair shop at the time) literally arrived in a regular envelop in a tiny baggie with an invoice.

Added in edit:As far as that play N trade goes. I like the people there. I never find much product I want there however. Whereas I've had better luck finding retro stuff I want at some of the other Play N trades in the area. Cool people there though. I've been there 20-30 times, some of the employees recognize me there by now.

The downside to that Play N Trade is the location. Living only a half a mile from there is one of the few ways to actually get to that play n trade since downtown Elmhurst has practically no parking. I usually park all the way down by Hamburger Heaven and just walk whenever I go to that one.

The Elmhurst Play N Trade is pretty good. They get some good stuff from time to time. I go there at least once a week since bank is right across the street. I am astonished to hear that you park all the way by Hamburger Heaven. You should park at the Chase/Walgreens parking lot right in front of the store. Chill out at Walgreens for a bit just to play it safe. I have found some pretty nice finds at Elmhurst PNT. In fact, I picked up Splatterhouse 2 and 3 for a combined $20 about a month and a half ago. The only other PNT i've been to is in bloomingdale right in front of Stratford mall, but I believe that one closed. Which ones do you like??

On a side note, I was surprised to see that the Microcenter carries 4.5 gamebits!! They are Out of stock but I'll visit the one in westmont and see if they'll order one for me.

http://www.microcenter.com/single_product_results.phtml?product_id=0335650

The parking by Walgreens is always full, I've had to park in the multi level parking which is only available certain hours closer to the train tracks a few times.

The Bloomingdale play n trade is terrible as far as what retro stuff they get, I work almost directly across the street from it and am there frequently, it's still in business (I saw a thing on Craigslist saying they were closed but they're still there) but it's not really visible from Gary Avenue and most people don't know it's there). As far as Play N Trades go, The better ones are Naperville, and North Aurora. I've also had good luck with Batavia.

In general People Play Games and Videogames etc have better product anyway.

But yeah, Elmhurst PNT is a nice store and it's much better than bloomingdale. But I've not had good luck finding stuff there.

[chany60126]

From the picture, appears you have the correct style bit.
DON'T understand it's ability to open a Genesis game.
Are the screws in the Genesis the same as the screws in your Duo?
Got anybody local to you that handles such matters?  Try Craigslist, if present for your vicinity.
Don't know what to tell you, unfortunately...strange.

I went to my local Play N Trade since they can repair anything, even retro. The repairs guy confirmed that it was definitely the wrong bit since it is not keyed in properly compared to the screws on the Duo. He even tried to open up an n64 system, but no dice. Too bad he couldn't find his gamebit. The screws on my Duo are the same ones as the Genesis carts. What a headache... Where did you buy your gamebit from??

Play N Trade's generally have trouble doing repairs for systems they either don't have an outside vendor to repair or are not in their guidebook.

Added in edit: After consulting a friend of mine who was employed at one. Most of what they do internally at his store is simple NES 72 pin connector swaps. Everything else they were sending out to a vendor. It's on a franchise by franchise basis apparently.

I'm guessing you went to the one next to the movie theatre in Downtown Elmhurst?

In any event, I bought the correct gamebit from Nintendo Repair Shop online.

Yep, I went to Play N Trade in Elmhurst, it's only a half mile from my house. The guy who does repairs, Steve, has worked with gamebits before. He seems to know what he is talkin about. He is excellent at soldering stuff as he has fixed many RROD for 360s. I will probably seek his advice on how to solder since I have never done that before. The guys there are awesome.

I will look into the nintendo repair site after I email the peops (ncsx.com) who sold me the wrong gamebit. I think.
There is a label on the baggie where gamebit came that says 22-1150. Did your gamebit have a similar description?

Thanks,

I've bought from NCS many many many times. Not usually had a problem. My gamebit (I bought two different ones from Nintendo repair shop at the time) literally arrived in a regular envelop in a tiny baggie with an invoice.

Added in edit:As far as that play N trade goes. I like the people there. I never find much product I want there however. Whereas I've had better luck finding retro stuff I want at some of the other Play N trades in the area. Cool people there though. I've been there 20-30 times, some of the employees recognize me there by now.

The downside to that Play N Trade is the location. Living only a half a mile from there is one of the few ways to actually get to that play n trade since downtown Elmhurst has practically no parking. I usually park all the way down by Hamburger Heaven and just walk whenever I go to that one.

The Elmhurst Play N Trade is pretty good. They get some good stuff from time to time. I go there at least once a week since bank is right across the street. I am astonished to hear that you park all the way by Hamburger Heaven. You should park at the Chase/Walgreens parking lot right in front of the store. Chill out at Walgreens for a bit just to play it safe. I have found some pretty nice finds at Elmhurst PNT. In fact, I picked up Splatterhouse 2 and 3 for a combined $20 about a month and a half ago. The only other PNT i've been to is in bloomingdale right in front of Stratford mall, but I believe that one closed. Which ones do you like??

On a side note, I was surprised to see that the Microcenter carries 4.5 gamebits!! They are Out of stock but I'll visit the one in westmont and see if they'll order one for me.

http://www.microcenter.com/single_product_results.phtml?product_id=0335650

The parking by Walgreens is always full, I've had to park in the multi level parking which is only available certain hours closer to the train tracks a few times.

The Bloomingdale play n trade is terrible as far as what retro stuff they get, I work almost directly across the street from it and am there frequently, it's still in business (I saw a thing on Craigslist saying they were closed but they're still there) but it's not really visible from Gary Avenue and most people don't know it's there). As far as Play N Trades go, The better ones are Naperville, and North Aurora. I've also had good luck with Batavia.

In general People Play Games and Videogames etc have better product anyway.

But yeah, Elmhurst PNT is a nice store and it's much better than bloomingdale. But I've not had good luck finding stuff there.

It's good to hear that the one in Bloomingdale is still open, I did see the ad on CL that it was closing. Very odd... There is a new PNT that just opened in Melrose on north ave. I will probably wait a little bit for them to accumulate some retro games.

People Play Games and Video Games Etc are awesome. Their prices for nes/snes games are a little iffy, but their assortment of T-16, neo geo, and other retro stuff definitely make it worth the trip to those locations.

Hopefully I can get a good gamebit soon. I would love to have my turbo duo's sound problems fixed before the Video Game Summit in Lombard comes along since I am heading the Turbo Fest booth. At least I have my T-16 + CD that works great, but that would be a big load to carry around.

[onetunafish]

Hello all!

I think I might have a similar problem, except with a CD-ROM 2 Unit.

Similar symptoms:

- Cd-rom audio goes silent or out of sync after a while in some games (ie rondo of blood)
- the cd-rom audio quality is really bad, cracks and static noise, even playing music cds
- In one game the sprites don't show up at all (martial champions)
- Every now and then the just a moment seems to go on forever

From what I've read, it might need to replace some caps, clean the laser lens and/or adjust it or even replace the whole cd reader. I couldn't find which caps to replace on the CD-ROM unit, would any body be kind enough to point those out to me? I took a quick glance at it but I didn't see any poped caps or signs of leakage but I'm no expert. Any help is very much appreciated.

Ed