Anybody know the Power amperage on the TI video out connector?

[Mitkraft]

I've installed the F18A mod and had already cut the RF modulator off of my video cable and added connectors for video and audio. One of my next projects will be to make an imitation TI brand monitor from the guts of a computer monitor placed inside the shell of a TV that bears a decent resemblance to the TI monitor. What I'm thinking about doing is putting speakers inside the TV and I'm wondering if I can't power them from the 12V power that originally powered the RF modulator. Does anybody know what the safe power handling capacity of that would be? Or would I be risking needless stress on the TI and should maybe just power the speakers separately?

 

Thanks!

[+save2600]

+1 for powering the speakers discretely.

[+Schmitzi]

+1 for asking, and not trying first

 

 

/Edit/ I have checked all my PDFs for max. consumption, sorry, no bonus

Edited April 17, 2015 by schmitzi

[+save2600]

Amplifying speakers is a tricky stuff. Too many variables here to make assumptions, even if you're just powering "small" or tiny speakers and never crank them up, you've got to look at things like impedance, current, volume output, etc. Best to just take the audio line out into a set of powered speaker(s). You've already got the F18, speech synthesizer and whatever else hooked to your system which is all being powered by a little (or large in this case) sealed wall-wart of sorts that already gets warm to the touch. Personally, I wouldn't risk it, even if you might get what you think is decent output out of such a scenario.

[Shift838]

I agree with Save.. I would not risk it. a set of powered speakers is the safest option.

[matthew180]

The F18A uses less power than the original 9918A, plus the DRAM chips are no longer used when the F18A is installed. You can completely remove them if you want additional power savings, or at the very least they are now sitting idle.

 

The 12V supply is pretty low from what I remember, and you would have to measure the console's 12V consumption to know how much would be available for your use. Or you can measure the current draw being used by the RF modulator and assume that is a safe value.

[Mitkraft]

Thanks for the replies. I'm might have given the wrong impression though. I was going to use the 12V to feed a set of powered speakers. I was going to feed them with the 12V line from the video out in place of their own power adapter. I'm pretty sure I have a set that was originally intended to mount below the monitor and got their power from particular monitors that had a special power connector. I believe it was 12v but don't remember the amperage requirements. I need to dig them out and check. I also have a similar set that was meant to be powered from a USB port. That might be an option as well and could tap into the 5V instead. But I also hear you guys saying "don't risk it" I was concerned as well to begin with.

[+Ksarul]

The original 99/4 had a very small internal speaker (under the grille behind the cartridge port), so the machine can drive a single speaker. The problem will be current draw. This document shows all of the specifications for the PEB and its circuit cards (including expected current draw), but it does not do the same for the console. I typed this one in as a restoration project a few years ago, as the only complete copy of it I'd ever seen was a really poor photocopy. I think I put one up at one point that gave the console the same treatment. I'll have to look some more to see if I can find it.

[Stuart]

Console power consumption:

 

http://www.avjd51.dsl.pipex.com/ti/ti.htm#power_supply_consumption

[Mitkraft]

Good info. Thank you all. I think what I'm going to go is power the speakers from their own adapter. I'd rather not risk the stress on the 30 something hear old hardware or add any extra heat inside the case.