Atari 7800 Power Supplies...

[Atariman]

How many different revisions did these things go through? Every time I have picked up a power supply for the 7800, it has been different.

 

The first one I came across is similar to the power supply that came with my master system. I then came across another type which just looks... kinda funky... and really old. And the one that I came across today is about the same as the NES power supply. How many different times did they revise their power supply?

 

The one picked up today was at my local game shop - they have a box that they keep untested stuff in which is where I noticed it. I inquired about it and was told that they would probably want top dollar for it as they aren't particularly common, so I decided not to bother - that is, until the other employee mentioned that water was dripping out of it. Rusty, brown water...

 

Needless to say, they no longer wanted it, so rather than watching them throw it in the trash, I said I'd take it. I didn't want to destroy the case, so I placed it upon one of those "erasers" that are used on belt sanders and lovingly smacked it with a rubber mallet. Over and over and over. One side eventualy gave, so I was able to pry it the rest of the way open with only minor damage.

 

Once inside, I noticed that the innards were pretty rusty, but the capacitor inside wasn't bulging, there was no scorching, and the actual windings of the transformer looked good. I washed the PCB, scrubbing it with an old tooth brush with some soap, and put it on top of an adjustable fan to let it dry. I had decided to let it dry for a few days before trying it out, but I was too inpatient to wait that long - it seemed dry enough and shaking it didn't result in water coming out, so I went ahead and soldered the transformer back to the prongs that are inserted into the power outlet.

 

After plugging it in and seeing no sparks or smoke (flinching as I inserted it into the outlet), I checked the voltage across the DC terminals - almost a perfect 9V! I went ahead and applied a small amount of super glue to the inside lip of the power supply and reassembled the case. Now if I just get around to fixing the broken wire on my other spare 7800 power supply, I'll have three between my two 7800s!

 

One other interesting thing I noted while disassembling the power supply - I pried up the metal label (since it was loose anyway) and noticed something rather peculiar - the label was covering the original "label" that had been pressed into the plastic! It appears that someone screwed up the part number as that is the only real difference that I noticed when I compared the information from both labels.

 

Perhaps not the most interesting thing to others, but I found all of these things at least a little bit intriguing...

 

Note the rust that is still inside the case and on the transformer - and this is AFTER I cleaned everything up! (A little CLR on the inside of the case got a great deal of the rust and other mystery metallic particles out)

[Bruce Tomlin]

The power supply isn't really the important part, it's the plug.

 

Sure, you can use an LED connector from an old PC, but it won't be polarized, so it's too easy to fry your console by plugging it in backwards.

[SINGLE TOOTH]

LED connector, thats a really good idea. But, like bruce here says, dont reverse the polarity.

[Atariman]

The power supply isn't really the important part, it's the plug.

 

Sure, you can use an LED connector from an old PC, but it won't be polarized, so it's too easy to fry your console by plugging it in backwards.

 

True, but I prefer "true" Atari-branded hardware, so I was happy to get this functional once again.

 

As for polarity, it shouldn't be too hard to add an additional piece to the LED plug to prevent reversing the polarity (or better yet, perhaps a simple diode could be installed in the 7800 - assuming that a little dip in voltage won't throw everything off)