Is there anyone with a known working karaoke attachment and a voltmeter willing to open it up and check the output connector voltages? I'm not getting any video output and I suspect the power supply is bad. I'm only getting mV readings on the pin closest to the front of the unit. Edit: for testing, I'm looking for the voltages present with only the power connected.
No video output, low output voltages, or both? How do you have it connected? My setup is: I'm using a PowerBright VC-100J for the 120V > 100V step down transformation (according to the silkscreen on the supply's PCB, it has an input range of 85 - 132VAC, so technically, the transformer isn't needed.). I have a NTSC-J Dreamcast attached to the Dreamkara unit using the Dreamkara's included pass through A/V and power cables, so the main power and A/V out cables are attached to the Dreamkara unit. As far as I can tell, the supply doesn't have a low power standby mode that's deactivated when the Dreamcast is turned on and powers up its G2 bus. It looks like the Dreamkara unit is always on at 5V.
I'm using a Japanese Dreamcast as well, I'm plugging the power direction into my wall. I'm in the States so a step-up or down converter is not needed. I have it hooked up the way its supposed to be. I suppose it'd be possible to separately power both, like Genesis and Sega CD, but I'd be afraid of destroying it.
Correct. Despite being set up correctly, I get no video out put. My assumption is a lack of sufficient power. But I really don't know.
We need to look elsewhere. I ran some some wire from the outputs to outside of the unit so I could put it back together just enough to connect the Dreamcast. When the Dreamcast was powered on, both outputs go to the expected 5V, so the G2 bus does take it out of standby by powering the unit enough to give the Dreamkara's power supply a proper load. I did a continuity check on the A/V connector that connects the Dreamcast to the Dreamkara and everything is OK there. The only other thing I can figure is there's a broken / cold solder joint on the A/V connector. Update after testing the A/V connectors: A continuity check shows the video can pass through just fine from the connector cable through the A/V IN and to the A/V out pin for composite video. The same for ground (both the shielding and the pin 1). Audio passes into the input fine, but nothing is showing up at the output. I suspect the reason for this is the input is being fed into a mixer for the microphones. That shouldn't affect the video... that signal should pass straight through. I have no idea what's going on. Even stranger is the software says it supports VGA, but that's impossible using the suggested configuration since the connector between the Dorikara and the Dreamcast is only capable of carrying composite.
you might want to look at the bottom of your japanese dreamcast and drikara, they are rated for 100volts. the us of a uses 110-120volt so you are ever so slightly overheating your equipment. so a step down transformer is needed to increase your longevity. smell your dreamcast when you plug it in vs your us dreamcast, it will be different.
Haha, oh are you going to like this then... I bet you've run the main output through to either an RF or VGA adapter, right? I did, but that won't work because it ONLY SUPPORTS THE COMPOSITE CABLE :banghead:. Those are hours I'll never get back, but at least I got some more experience checking over switching power supplies and I got some nice high resolution scans of the boards in the unit.
If you had watched/remembered/believed Retrocore 25, you would have known a while ago http://www.archive.org/details/RetroCore-Volume25 (dorikara starts at +- 45:00)
Yeah to be honest I never even checked it with a composite connection. I didn't have enough of a desire to play a karaoke game I couldn't sing to anyway.
