New power adapter

[+batari]

This is the promised 7800 power adapter.

 

 

It takes a bog-standard 12v PSU. This accepts either tip polarity, or AC. The circuitry converts to the proper polarity on the 7800 so there is no guesswork involved and you can use a wide variety of AC adapters. If the AC adapter plugs in and outputs at least 1A, it will work!

 

It is available with either a 2.1mm or 2.5mm adapter, and one will be created that has both plugs. 2.1mm is shown.

 

This converts 12v to filtered 9v at up to 1.5A. It would also likely work with voltages from as low as 10v to over 20v, though 12v is recommended.

 

This is PSU I had lying around, and I'm not sure what it's for.

 

 

When I first plugged this in, I was shocked at how clear the RF was to the TV. It looks like all along, the PSU I was using was a cause of RF interference. I wasn't expecting that!

 

The tiny PCB itself acts as a heat sink, as the regulator is soldered directly to the copper ground plane on the PCB. It gets a little warm to the touch but not excessively hot. A non-contact thermometer shows the temperature after running a game on a Concerto cart for an hour.

 

 

The final version may have an additional heat sink but it seems to not really need one.

 

I am still looking for a source for a plug that fits into the 7800. The one shown above fits but the positioning notch was too narrow. Looking for something that already exists and is designed for electrical applications with at least a 1A capacity. A 3D printed plug is a possibility only if nothing suitable can be found.

[+-^CrossBow^-]

They don't have as many...but console5 has wire harnesses with the right plug on the ends of them. I was buying up a few when i was making my barrel jack adapters to use with them last year.

 

 

[+batari]

6 hours ago, -^CrossBow^- said:

They don't have as many...but console5 has wire harnesses with the right plug on the ends of them. I was buying up a few when i was making my barrel jack adapters to use with them last year.

Thanks, though the price is too high. $5 each just for the connector means that every adapter costs more to make than it could sell for.

[+-^CrossBow^-]

3 minutes ago, batari said:

Thanks, though the price is too high. $5 each just for the connector means that every adapter costs more to make than it could sell for.

That is why my adapter cables I had to sell for $15 shipped. It cost me nearly 10 in parts alone for everything in such a small quantity and between $3 - $5 to ship them to various places 1st class at the time. That is why I didn't make more even though I wanted to. I had hoped another would buy in larger bulk to take over and offer them to the masses at a lesser price.

 

Aside from C5, I'm not sure of any other places to get them. From what I can tell, even on the DF cart that passthrough cable I think is 3D printed?

 

[rj1307]

Yes, in Dragonfly I use a plug printed on the printer and contacts like this: https://www.tme.com/us/en-us/details/hdp20-1662911/d-sub-plugs-and-sockets/te-connectivity/166291-1/

In addition, 0.5mm wires that I solder and not clamp to the contacts.

 

 

[+batari]

That 3D printed plug looks good and is probably the only option, as I just can't find anything out there that will work. I would need a strain relief with mine though as the board hangs from it and that will be further attached to the 12v power cable.

[NISMOPC]

WOW! Looking forward to this.

 

My 7800 daily use power supply buzzes and interferes with TV via speakers.

 

Was planning on a modern type adapter, but this will be perfect since I have several PSU's that are similar to the one you are using.

[christo930]

On 1/13/2021 at 1:17 AM, batari said:

This is the promised 7800 power adapter.

 

 

It takes a bog-standard 12v PSU. This accepts either tip polarity, or AC. The circuitry converts to the proper polarity on the 7800 so there is no guesswork involved and you can use a wide variety of AC adapters. If the AC adapter plugs in and outputs at least 1A, it will work!

 

It is available with either a 2.1mm or 2.5mm adapter, and one will be created that has both plugs. 2.1mm is shown.

 

This converts 12v to filtered 9v at up to 1.5A. It would also likely work with voltages from as low as 10v to over 20v, though 12v is recommended.

 

This is PSU I had lying around, and I'm not sure what it's for.

 

 

When I first plugged this in, I was shocked at how clear the RF was to the TV. It looks like all along, the PSU I was using was a cause of RF interference. I wasn't expecting that!

 

The tiny PCB itself acts as a heat sink, as the regulator is soldered directly to the copper ground plane on the PCB. It gets a little warm to the touch but not excessively hot. A non-contact thermometer shows the temperature after running a game on a Concerto cart for an hour.

 

 

The final version may have an additional heat sink but it seems to not really need one.

 

I am still looking for a source for a plug that fits into the 7800. The one shown above fits but the positioning notch was too narrow. Looking for something that already exists and is designed for electrical applications with at least a 1A capacity. A 3D printed plug is a possibility only if nothing suitable can be found.

Mold the plug.  I'm really surprised this is less well known in the vintage gaming hobby, but you can get silicone molding compound and pourable resin pretty cheap.  Once you make a mold, you can pour as many copies as you want.  With such a small item, you can easily make a multi-copy mold where one pour will give you 5 plugs.

You can copy anything plastic (or metal or wood) using this method.  The silicone mold picks up detail so well that you can literally copy records that will play on a record player. New copies of very rare Edison Diamond Discs are being produced this way.

Even if the original is broken, you can just glue it together for the mold, just making sure you sand the repair otherwise all of the copies will appear to be repaired.

[doubledown]

1 hour ago, christo930 said:

Mold the plug.  I'm really surprised this is less well known in the vintage gaming hobby, but you can get silicone molding compound and pourable resin pretty cheap.  Once you make a mold, you can pour as many copies as you want.  With such a small item, you can easily make a multi-copy mold where one pour will give you 5 plugs.

You can copy anything plastic (or metal or wood) using this method.  The silicone mold picks up detail so well that you can literally copy records that will play on a record player. New copies of very rare Edison Diamond Discs are being produced this way.

Even if the original is broken, you can just glue it together for the mold, just making sure you sand the repair otherwise all of the copies will appear to be repaired.

Do you think this molding compound concept would work to make a good mold of this small power plug, which has two holes that run through its length?

[christo930]

45 minutes ago, doubledown said:

Do you think this molding compound concept would work to make a good mold of this small power plug, which has two holes that run through its length?

Yes, but not the whole length.  A piece of tape would have to cover one side of the holes in order for a mold to work. Then you would have to poke a hole through the finished product. 

 

If you only need one of something and you are very good at 3d printing (designing), 3d printing may be the way to go.  But anything you will need many of, definitely molding is the way to go.  Once you have the mold, you can just keep it.  There is a lot you can do with the resins. They come in many different strengths, cure times and you can custom color them as well by using pigment compatible resign.  There are a lot of videos on YT showing how do to it.

The only time I have ever seen this method in classic gaming is on a handheld repair channel.  This was especially helpful in Tomy electromechanical toys that use things like gears and battery covers.

 

A really nice thing about using this method is you can repair broken parts, repairs that would never hold, and then mold repaired part. But an even bigger nice thing is you can make custom parts from either modeling clay or wood or anything else really. All you need is the correct shape of an original. Then you can just pour unlimited (practically) copies.

My windows are old and all of their functionality of going up and down and tilting are all enabled by plastic parts. You cannot get the plastic parts anymore. So for $10 in plastic parts, thousands of dollars of windows need to be replaced.  I have made some replacement plastic parts and so-far so-good.  I don't know how this resin based plastic will hold up to the realities of sitting in a window, but I just don't have 20 grand burning a hole in my pocket to buy new windows.  But of course, I still have the molds and these are a 5 minute job to replace them. So if I have to replace them every couple of years, no big deal.

[doubledown]

On 1/13/2021 at 1:17 AM, batari said:

This is the promised 7800 power adapter.

 

Please understand that this is not a snarky or sarcastic comment/question at all...but a true curiosity, I preempt this question with this note, as tone and sarcasm are often inferred and/or misinterpreted.

 

So what you're looking to provide/offer, is this small power board to 7800 console adapter plug (pictured next to the quarter), which will be powered by a separate 12V power supply (that the user will provide), to provide the necessary 9V to the 7800.  Is this correct?  Is there any reason, as to why not just use a new 9V power supply (re-create the "stock" wall-wart concept)?  Obviously the new 9V P.S.'s factory plug end would need to be be changed to the 7800 compatible version.  Again, I'm just curious, and maybe there is something I'm not quite understanding.  

[+DrVenkman]

On 1/13/2021 at 12:17 AM, batari said:

It takes a bog-standard 12v PSU. This accepts either tip polarity, or AC. The circuitry converts to the proper polarity on the 7800 so there is no guesswork involved and you can use a wide variety of AC adapters. If the AC adapter plugs in and outputs at least 1A, it will work!

 

9 minutes ago, doubledown said:

Is there any reason, as to why not just use a new 9V power supply (re-create the "stock" wall-wart concept)?

Um, did you read the post you quoted?

[doubledown]

Just now, DrVenkman said:

 

Um, did you read the post you quoted?

I did, then I quoted it, then I asked a question about it.  

[+-^CrossBow^-]

I think the idea on this is to allow someone the ability to use any other supply that likely already have on hand. Specifically a Sega power supply or NES power supply as an example? That is my take away on this?

 

Again, back in Sep - Nov of last year I created a simple wire adapter harness that allows you to use a sega PSU on one end and plug it into the 7800 power port on the other. This does the same but doesn't care about the polarity etc and allows for more universal PSUs instead of a specific series.

[doubledown]

9 minutes ago, -^CrossBow^- said:

I think the idea on this is to allow someone the ability to use any other supply that likely already have on hand. Specifically a Sega power supply or NES power supply as an example? That is my take away on this?

That's kind of what I was thinking too, but I just wasn't sure.  If this power adapter is to be a very inexpensive adapter / partial power solution for the 7800, then I suppose I could see the draw for some budget-minded people.  Me personally, I would just assume have a single component, dedicated power adapter for the console.  As it is now, I have 2 7800 consoles, and 2 original power adapters...1 of which is starting to fail, and that I will need to replace.  I just assumed that I would buy a new 9VDC power supply, and splice the 7800 adapter end onto it's cable, unless somebody knows some reason why this wouldn't work.  And looking at the original post, he mentions feeding his adapter with 12V, so I don't think the Sega or NES power supplies would work...don't they only output 9V?  

 

Again, I'm not saying anything negative about this, and I am by no means an expert in the 7800 scene...that's why I was asking.  If it's known by some that off the shelf modern 9VDC power supplies (once they have the correct connector on their cable) won't work properly with the 7800, and this circuitry/adapter is a solution for that, than I would understand it more.  

[+DrVenkman]

4 minutes ago, doubledown said:

If it's known by some that off the shelf modern 9VDC power supplies (once they have the correct connector on their cable) won't work properly with the 7800, and this circuitry/adapter is a solution for that, than I would understand it more.

Most modern wall-wart supplies are super-cheap, very efficient switch mode devices. They are cheap, reliable and produce much less waste heat to provide the voltage and current required. Problem is, switching PSU’s also produce electrical, RF noise from the high-frequency switching that occurs inside. Modern devices are designed with this in mind and filter it out. Vintage devices, not so much. The beauty of Fred’s device is that it allows almost any old modern PSU you probably have sitting in a box somewhere from an old router, cable box, external hard drive, etc. to be used with your 7800 without regard to tip polarity or RF noise.

[+-^CrossBow^-]

I believe his 12v statement was actually talking about output voltage without a load on it. I know that most of my Genesis PSUs and even my 7800 PSU put out 13 - 14v without a load on them. At the input side of my regulators they measure just over 12v input.

 

[eightbit]

3 hours ago, -^CrossBow^- said:

I think the idea on this is to allow someone the ability to use any other supply that likely already have on hand. Specifically a Sega power supply or NES power supply as an example? That is my take away on this?

 

Again, back in Sep - Nov of last year I created a simple wire adapter harness that allows you to use a sega PSU on one end and plug it into the 7800 power port on the other. This does the same but doesn't care about the polarity etc and allows for more universal PSUs instead of a specific series.

 

 

And I will attest to your adapter as being one superb thing. It has been in use on my 7800 since I received it from you

 

Too bad it is so cost prohibitive to make more of these.

[doubledown]

On 1/13/2021 at 5:08 PM, -^CrossBow^- said:

That is why my adapter cables I had to sell for $15 shipped. It cost me nearly 10 in parts alone for everything in such a small quantity and between $3 - $5 to ship them to various places 1st class at the time.

14 minutes ago, eightbit said:

Too bad it is so cost prohibitive to make more of these.

I don't feel that a $15 adapter (plus the necessary power supply), that allows one to keep their 40ish-year-old hardware working and playable...expensive at all, personally.  Anybody who wants to be in the vintage gaming hobby (with actual hardware, not emulation), needs to understand that it won't all be cheap, and/or easy.  And if such an adapter, at such a price, is too much for some...then they should just get out of the hobby, and play old games in emulation on their smart phones, while they're sitting on the toilet.  Just sayin'!

[+-^CrossBow^-]

Well, my adapters weren't anything special. I was just using a female barrel jack on end to allow use of the SMS,Jaguar, Genesis PSUs that was wired to a 7800 plug on the other end. Again, it was to provide a no modification method of using an alternate PSU that might be more common and easy to get vs one specifically made for the 7800 with the right plug on it. Like you I would just cut the wire off my old supply if and when it dies and splice it onto another brick and use it. But not everyone is so inclined to want to do that or feel comfortable doing that. The actual parts cost came to $8 not including the shipping of the parts to me or tax I paid for them. I was including the shipping on them as well. Some labor was spend on each one sure, but I was pretty much selling them at the cost of parts and shipping when I made them. I only made about 20 of them all told. I also made one for myself that allows use of the 5200 PSU on the 7800.

 

I originally made them to limit how many different PSUs I need on my bench when servicing consoles to test stuff.

 

[+DrVenkman]

50 minutes ago, -^CrossBow^- said:

I originally made them to limit how many different PSUs I need on my bench when servicing consoles to test stuff.

Yeah, I have a regulated bench PSU for stuff that uses DC but the need to wire up the combo of DIN jacks (XL computers), and a couple different barrel jacks and plugs for different systems is frankly a PITA. 

[eightbit]

4 hours ago, -^CrossBow^- said:

Well, my adapters weren't anything special. I was just using a female barrel jack on end to allow use of the SMS,Jaguar, Genesis PSUs that was wired to a 7800 plug on the other end. Again, it was to provide a no modification method of using an alternate PSU that might be more common and easy to get vs one specifically made for the 7800 with the right plug on it. Like you I would just cut the wire off my old supply if and when it dies and splice it onto another brick and use it. But not everyone is so inclined to want to do that or feel comfortable doing that. The actual parts cost came to $8 not including the shipping of the parts to me or tax I paid for them. I was including the shipping on them as well. Some labor was spend on each one sure, but I was pretty much selling them at the cost of parts and shipping when I made them. I only made about 20 of them all told. I also made one for myself that allows use of the 5200 PSU on the 7800.

 

I originally made them to limit how many different PSUs I need on my bench when servicing consoles to test stuff.

 

 

 

Well, the special part of yours was that unique connector that you used. It is exactly the same as a 7800 PSU connector, just not blue. And it was not 3D printed. I think you said it was from some kind of phone charger adapter cable that was a perfect match?

Edited January 15, 2021 by eightbit

[+-^CrossBow^-]

I believe the wire ends I used in those (I got them from Console5.com btw), might have come from some battery charger device if I remember? Sometime back someone found an auction on ebay or the like where there were hundreds of these dead chargers being auctioned. They all used the same connector as the 7800 required and I thought console5 had worked out a deal to acquire all of them.

 

[eightbit]

There must be connectors out there somewhere. It looks like some type of JST 2-pin connector type. Just a matter of finding out which one

[+batari]

9 hours ago, doubledown said:

Please understand that this is not a snarky or sarcastic comment/question at all...but a true curiosity, I preempt this question with this note, as tone and sarcasm are often inferred and/or misinterpreted.

 

So what you're looking to provide/offer, is this small power board to 7800 console adapter plug (pictured next to the quarter), which will be powered by a separate 12V power supply (that the user will provide), to provide the necessary 9V to the 7800.  Is this correct?  Is there any reason, as to why not just use a new 9V power supply (re-create the "stock" wall-wart concept)?  Obviously the new 9V P.S.'s factory plug end would need to be be changed to the 7800 compatible version.  Again, I'm just curious, and maybe there is something I'm not quite understanding.  

Anyone with the skills to convert a 9v adapter to the proper polarity and proper output plug can do so and get by without ever needing this. However, even if you do that, you are relying on the output from some random adapter being correct and clean enough to not impart interference to the 7800.

 

This adapter does several things.

 

1. 12v is more common than 9v and most likely there is no need to buy a new adapter.

2. It eliminates guesswork and possible damage from wrong polarity: You don't need to worry about output polarity or even if the adapter outputs AC, as long as it outputs 1A or more in current.

3. It produces clean, regulated 9v output even from pure AC, and even with no load (other adapters produce 14-15v unloaded, and under load, maybe not even 9v, and the voltage may fluctuate significantly.)

4. It should protect from some voltage spikes entering the 7800.