The NEW Build Your Own Arcade Controls
Main => Consoles => Topic started by: jasonbar on August 13, 2009, 04:07:45 pm
-
Anybody know what would cause a Dreamcast to get extreeeeemely quiet?
One day it was fine, & the next day, I need to turn my AV receiver all the way up to "MAX" to be able to hear it, and even then, it's pretty quiet. With any other game system plugged into the same input jacks on my receiver, I can't get anywhere near "MAX" on the volume knob before I'll go deaf.
Any ideas?
Sounds as if an audio amp in the Dreamcast pooped out...?
Thanks,
-Jason
-
Could just be the cables themselves. Try to find some replacements first.
-
if its on RF try re tuning it again on another spare channel and also try twisting the aerial lead in and out of the tv very slowly whilst the tv is off because the sound cut out on me just yesterday and after fiddly with the cable it worked out fine.
Also as hypernova said try a different cable.
and you could also try soldering an audio port on to the main board like in the vga mod http://www.mmmonkey.co.uk/console/sega/dc-vga.htm as the A/V port may be failing.
worth a shot :)
-
Thanks for the ideas.
I'm not using an RF connector. I'm using an S-Video cable w/ individual RCA left (white) & right (red) plugs.
I doubt that both the left & right cables would go bad simultaneously. Smells like a problem inside the DC to me...
Thanks for the link, but if those 3 points on the PCB (ground, left, right) are after an audio amp, or at least shorted directly to the AV cable jack, then I think I'll get the same results by using audio off of those pads as I'm getting now...
Thanks,
-Jason
-
Well, I've got good news & bad news.
Plugged the Dreamcast in tonight. Sound works great. That's good. But the fact that it's inconsistent is bad.
Kept getting lots of resets too.
Think it's time for a new Dreamcast--they seem to be pretty cheap around here...
-Jason
-
glad your sounds back :)
for the resets at least give http://www.mmmonkey.co.uk/console/sega/dc-reset.htm a go :) it sorted mine out brilliant, i just took out the power board and rubbed some kitchen towel over the pins bending them ever so slightly and it works great - not had a reset since.
-
Another +1 for the reset fix on that page. Not mine, but a friends dreamcast kept doing this badly (usually under a minute from power on) so I said I would have a go for her. Many nights of problem-free dreamcast gaming ensued.
-
http://web.vtc.edu/users/cph11120/DreamcastProject/Schematics/AudioOutSchematic.htm
The (common) audio components seem to be mostly passive with the exception of IC304, so if you had any intentions of attempting a fix, I'd start there. The only other common chip is the D-A converter, and if you've got any sound at all thats probably working.
I've never actually opened my DC, but I suspect that by the time you source a surface mount part, get the old one out, the new one in, etc, it'd be easier to find one on Ebay. :)
-
I got my extra DC from www.chasethechuckwagon.com :nlp for $25 shipped with 2 games and 2 controllers
-
Having a quick look through the schematics there, I'd say definitely have a look at the operational amplifier IC, IC304A & B and transistor TR302. I know a replacement dreamcast could be cheap but if a piece of dreamcast hardware can be fixed I think it should be :) Fantastic system
-
I got my extra DC from www.chasethechuckwagon.com :nlp for $25 shipped with 2 games and 2 controllers
":nlp" :laugh2:
Having a quick look through the schematics there, I'd say definitely have a look at the operational amplifier IC, IC304A & B and transistor TR302. I know a replacement dreamcast could be cheap but if a piece of dreamcast hardware can be fixed I think it should be :) Fantastic system
Oh yeah, TR302 is common. Not quite sure its purpose - might be a limiter of some sort. Since the other two transistors short the audio directly to ground, perhaps TR302 is the common trigger? Signal gets too high and it clips it?
Seems like that would have been easier to do by changing the gain on the opamp.
-
Oh I hated opamps, I could never get my head around them. My philosophy is, if its in the circuit and somethings not working, replace everything! I had 4 batch replacements of components on my first arcade monitor till it worked, capacitors, resistors, ic's then finally transistors.
Of course as you say, dreamcast probably is surface mount so I'm not sure how accessible those components would be... I do remember seeing some full size components when fixing that reset bug so he might be in luck.
I'd have a look at mine, but I've not been able to get the screws out of my dreamcast! The little ones just slip out under any duress and my really large screwdrivers are too wide to fit into the recessed holes. Never had any trouble with other dreamcasts though :S
-
Thanks for the link--that was handy. I cringed, opened up my Dreamcast, & bent & cleaned the pins. Played for 1-2 hours with no resets or other weirdness. Hope it's good now, thanks!
Cringed? Oh, that's just because this Dreamcast sent me to the emergency room when I was trying to resolder a button battery to the circuit board & ended up shorting & blowing up the battery & getting the full blast of hot Lithium in my eyes. It's amazing how fast burned & abraded corneas heal! I later installed a battery holder on leads to the circuit board so that I could do all my soldering with no battery in place & then just pop in the battery later...
Anyway, the only final weirdness on my Dreamcast is that I have to enter the date every time I turn it on & most power-ons also send it to the menu screen instead of just booting the game. I'm guessing that the new battery's not doing its job? I presume that a good-battery Dreamcast should just boot to a game when powerd on?
Thanks,
-Jason
-
Anyway, the only final weirdness on my Dreamcast is that I have to enter the date every time I turn it on & most power-ons also send it to the menu screen instead of just booting the game. I'm guessing that the new battery's not doing its job? I presume that a good-battery Dreamcast should just boot to a game when powerd on?
Are you cutting power to the Dreamcast? Even with a battery it'll only hold a charge and keep the current time for a few hours. Ultimately you'll need to keep it on a regular source of AC power if you want it to remember the time. But this has been fairly standard on a LOT of consoles.
-
Yah, when I don't use the DC, it's in a box in the basement.
So, that battery backup for the time lasts only a few hours? That seems rather weak...no point in ever replacing the battery on that console then (for me)...
Thanks,
-Jason
-
.. a replacement DC battery should last a lot longer.. i believe the original was about 200mah.. i've replaced mine with a batterypack and 2 AAA batteries about 2000mah and it lasts at least a day.. although i've just done it and haven't actually tested how long it can last
and if you go into the setup you can enable or disable autoboot in there.
-
Thanks--still seems like an awfully short period to keep time, considering that a similarly sized watch battery can keep time for months, if not years, in your wristwatch... :dunno
Thanks--I did set that autoboot option in the menu, but it didn't stick--maybe now that I've got more stability, I can try that setting again & see if it sticks this time.
Thanks,
-Jason
-
Thanks--still seems like an awfully short period to keep time, considering that a similarly sized watch battery can keep time for months, if not years, in your wristwatch... :dunno
The hardware in a console is minimalist and often functions arn't key get sidelined. The clock in the DC likely isn't nearly as power efficent as you'd see in, say, a PC. The same thing happened with the Xbox. It's clock was built into the Northbridge which isn't where it typically goes in a PC. It consumes like 50 times the power as a PC's clock. This still isn't a LOT, but it means that on batteries the Xbox would drain the battery in a month. The battery would be dead before it could be shipped, shelfed, purchased and opened by the user. Instead the Xbox uses a HUGE capacitor the size of a C cell battery that can power the clock for 2-4hrs.
Finally it IS just a game console. It mostly lives it's life next to the TV. Keeping time correctly and at all times isn't exactly critical to it's operation like time keeping on the PC is.