Help: Twin Famicom shows a signal for a split second, then seems to power off

[amc3]

Hi Famicom Lovers,

I'm still trying to get my Twin Famicom up and running. When I turn on the power while it's in disk mode, I hear the music for the "Please set disk card" screen for just  a split second and then it stops and my TV says there's no signal. I never see the red power light come on on the console.

If I repeatedly turn it off and on several times, I probably get the split second of music one out of five times. When a disk is in, the drive spins up and does one pass, then spots. No signal ever goes to the TV.

With a cartridge in, I also get no signal and no power light on the console.

Is this a power problem? I'm using a Radio Shack AC adaptor, 2.5 A, toggling between 7.5 and 9V, just to try that. Tip (inner contact) is positive. Fit feels tight in the console.

Thanks so much for any help!!
Post Merge: September 17, 2016, 03:15:42 pm
Big breakthrough but one that's only leaving me a little more confused: I unplugged the yellow video RCA cable from the Twin and plugged it into a DVD player's RCA video (yellow) out. Turned on the DVD player and turned on the Twin. Now I hear the FDS theme song as expected, while seeing the video from the DVD player. If I put a disk into the FDS (Metroid), I even hear its audio playing just as expected.

If I unplug the video from the DVD player, my TV says there's no signal at all and I lose the audio. (I understand that most TVs look for a video signal to determine whether there's any signal at all on a given input, so this makes sense.)

But what's going on here? Is it some kind of problem with the video out on the Twin?

Feeling close!! 
Post Merge: September 17, 2016, 07:58:23 pm
Another update: With the Twin in cartridge mode, the power on, and both the yellow and white video & audio cables connected to the TV, I tried unplugging and replugging just the video cable from the Twin. When the video cable was unplugged, the TV was giving a definitive "no signal". And most of the time, I saw the TV respond the same way it did when I powered up the Twin: seemingly detect a signal for a split second, and even produce audio during that split second. But then it would go back to "no signal".

But a couple of times of unplugging and replugging the video cable, the TV actually showed the video signal (and therefore also played audio)! One weird part is that the video was crystal clear but in black and white.

And then if I tried unplugging and replugging the video again, I went back to it usually not working...

Would love some thoughts...   
Post Merge: September 18, 2016, 05:05:57 pm
Yet another update:

I bought a composite to HDMI converter like this one from RadioShack https://www.radioshack.com/products/radioshack-composite-to-hdmi-converter and plugged the Twin into it and the HDMI out into my TV. IT WORKED. But there are lots of "artifacts" that actually look a little like JPEG or MPEG-4 compression, where you see things moving near the actual pixels that are animating. I might take the time to try to shoot a video of what I mean.

In the meantime, I also called Vizio support (just for fun; didn't expect much from it) and randomly got connected to a support person in Kansas who says he was "also a retro game enthusiast". He explained that the reason that the TV was essentially acting as though there wasn't a signal in the component/composite input was that "the TV has a higher refresh rate than most vintage consoles". I guess that explains why it worked when I converted it to an HDMI signal...And I guess that in those rare cases that it did work (after unplugging and replugging repeatedly), the TV was still considering it a component signal, rather than a composite signal, which is why it appeared black & white?


But I'm ultimately not satisfied with what that HDMI conversion produced. Anyone have any ideas on how to get a Vizio M50 to detect a composite signal from a Twin?

[Pikkon]

Looks like your tv does not like 240p.

Did you try the twin fami on another tv.

[amc3]

Haven't been able to try it on another TV. But that's definitely something I can and should try. Thanks for the suggestion.

What are my other options for making this work with this TV?
- Do the NESRGB mod to the Twin?
- Buy a $360 Framemeister? (Or would I have to first mod the Twin before I can use it with a Framemeister?)
- Keep using some composite to HDMI upscaler? (Are there better quality ones out there?)

Thanks!

[Pikkon]

The NESRGB will work just fine on a twin,if you can mod it yourself you will save a good chunk of money.

A framemeister would be ideal as it can upscale rgb,component,s-video and composite but even on a framemeister upscaling composite will still look bad.

Guess it depends on your budget and how much you want to spend,the cheapest option would be to find a old crt tv and use that on your twin fami.
And there's the retrousb avs system out now at a good price and can play fami/nes and outputs hdmi.