INTV II power supply options

[YannAros]

Hi,

 

I've posted this in an old thread but it might not show up anywhere:

 

I'm working on an NTSC INTV II in order to install my RGB mod inside.

I do not have the power supply that comes with it, is it 100% sure I can power it with 9-10V DC voltage. I have a lab power supply that will limit current in case but I want to be 100% sure before doing anything wrong.

This INTV II is not mine and I don't want to break anything.

 

Here is a picture of it's internal, what makes me doubt is the presence of a trafo on the power supply PCB that should only work with AC voltages, unless there is a kind of power switching mechanism after the first AC to DC conversion to create some higher voltages again.

I haven't found any schematics of the power supply board so I can't confirm / infirm anything.

 

Thanks a lot,

YannAros

[+-^CrossBow^-]

I use my 5200 PSU to power my Intellivision 2 when I want to use it for some reason (which, is rare honestly). But that is what I was using with it the last time it was really used when it was powered on for about 10hours during a convention about 5 years back. No issues.

 

However, I do have an issue I see in that pic you posted. The main voltage rail fuse has been replaced with a simple lead jumper?! Should be a small pico fuse mounted there. Or at least he NTSC units do.

 

[YannAros]

Thanks,

 

Atari 5200 is using 9V DC, so I  should be OK with my bench power supply.

I powered it up with a C64 power supply replacement outputing a beefy 9V AC and everything went fine.

 

Regarding the lead jumper at the place of the fuse it looks like factory mounted.

The console is a NTSC one, coming directly from the US, as far as I know there are not PAL INTV II;.

 

[+-^CrossBow^-]

Well, there should be a small pico fuse mounted there. I had to replace a burn out one in another Intelly II a few years back. 

 

On interesting thing I noticed with that Intelly 2 once it was brought back to life. Using the original Intv II AC power adapter that came with it, it would buzz quite audibly when plugged in and running. Using a 5200 PSU on it, it was quiet as a mouse. I'm assuming the AC through the transformer was the cause and that was essentially bypassed with a straight 9V DC running to it at that point.

 

 

[jsoper]

5200, Jag, and TG-16 will all work

Deathskull labs

[+-^CrossBow^-]

Jag and TG-16 won't work because the center diameter on those plugs is too small. At least now without changing out the power plug that plugs into the Intv II console. The Intv II uses a 2.5mm center pin size like the 5200. Not the 2.1mm found on Jag, Genesis,SMS, and TG-16. 

 

 

[YannAros]

As is it is quite noisy, I’ll try with a dc power supply tomorrow

[the_crayon_king]

1 hour ago, YannAros said:

As is it is quite noisy, I’ll try with a dc power supply tomorrow

Make sure to use a center-positive adapter. You probably already knew that but it is worth a mention just in case.

I had to learn that lesson the hard way many years ago.

[mr_me]

If the unit takes ac power, does it matter if it's center positive or negative.

[+wongojack]

18 hours ago, jsoper said:

5200, Jag, and TG-16 will all work

Deathskull labs

I have always remembered this quote from Deathskull - LOL: 

 

That 16.7V jazz is utter horseshit. I can't believe people go to such extreme measures to find a substitute power supply for these things. It's actual power requirements are about as generic as they get.

 

And @mr_me is right (I think he's always right).  The polarity doesn't matter since the Intv II takes AC power.

 

Edit - you also just taught be about the Arcade Archive, so thanks for that.

[YannAros]

12V DC worked perfectly! it draws 0.6Amps, so a generic 12V/1Amp power supply will perfectmy do the trick!

 

Thank you all for your inputs! 

[+-^CrossBow^-]

3 hours ago, YannAros said:

12V DC worked perfectly! it draws 0.6Amps, so a generic 12V/1Amp power supply will perfectmy do the trick!

 

Thank you all for your inputs! 

And that is why I use a 5200 PSU. Like most PSUs back then they are rated to output 10 - 9v but in reality it is more like 14v without a load. Again the internal system drops it down to the voltages needed anyway.

[the_crayon_king]

16 hours ago, mr_me said:

If the unit takes ac power, does it matter if it's center positive or negative.

No., or at least not as far as I can figure. I had forgot that the console that I work on literally every day is AC.  My brain is foggy after the vaccine. So I am slightly out of sorts.

 

To amend my previous statement; I still generally recommend not keeping a center negative adapter at all if you are collecting random old consoles (which often come sans adapter). I have never seen a console that has center negative as an input so I use the same center positive adapter to run maybe half a dozen consoles. Having a center negative around for my specific situation would be a liability since I would eventually pop it into one of the other consoles and possibly damage it. This is probably wildly unhelpful since this situation probably only applies to a few people.

[+-^CrossBow^-]

10 hours ago, the_crayon_king said:

I have never seen a console that has center negative as an input so I use the same center positive adapter to run maybe half a dozen consoles. Having a center negative around for my specific situation would be a liability since I would eventually pop it into one of the other consoles and possibly damage it. This is probably wildly unhelpful since this situation probably only applies to a few people.

Sega Master System, Sega Genesis, Jaguar, Most Roland Module PSUs all use center negative polarity on them. I might have as many devices in my house that use center negative as I do devices that use center positive. 

 

[the_crayon_king]

13 hours ago, -^CrossBow^- said:

Sega Master System, Sega Genesis, Jaguar, Most Roland Module PSUs all use center negative polarity on them. I might have as many devices in my house that use center negative as I do devices that use center positive. 

 

My GX4000, Action Max, Arcadia 2001, O2 (AC), Socrates, Intellivision 2 (AC), and 5200 all use the same DC center positive adapter.

 

My Genesis, SMS, NES (AC), and Jaguar all use the Genesis adapter (center negative DC adapter).

 

Looking through everything as long as I use the same adapter for everything except SEGA and the Jaguar it works.

 

[+-^CrossBow^-]

hehe.. see you are naming systems that are essentially alien to me minus the 5200 and Intelly. I've heard of the Arcadia but haven't played on one much less own one.

 

I guess my point was that you stated you hadn't seen a console that uses center negative. I was just stating that there are in fact well known gaming consoles that use that polarity configuration.

 

[the_crayon_king]

11 minutes ago, -^CrossBow^- said:

hehe.. see you are naming systems that are essentially alien to me minus the 5200 and Intelly. I've heard of the Arcadia but haven't played on one much less own one.

 

I guess my point was that you stated you hadn't seen a console that uses center negative. I was just stating that there are in fact well known gaming consoles that use that polarity configuration.

 

You are correct about many consoles being center negative. I really should think before I say things.

It looks like after a certain time period things shifted from being mostly center positive to mostly center negative.

What I am doing is probably not relevant to others.

 

I guess do whatever works to not allow yourself to use the wrong polarity (when it matters) which is not relevant to the Intellivision model 2. The polarity is something people sometimes overlook (myself included) which has more drastic consequences. Using a AC adapter on console that requires DC is also probably really bad.

[YannAros]

After having solved the power supply issue I still have questions about the Inty II. One issue we have seen on the Inty II we are looking at is high level of noise in the sound channel. The noise is getting lower when game is actually playing something but it remains quite higher than what I’m used too with INTV 1 models.

Is this normal? Is there something that can be done to improve ?