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Atari 800 broken SIO port


Veteran Member
Mar 9, 2019
Cleveland, OH
Does anyone know where I can source a replacement SIO port for an Atari 800? I have an 800 I've been fixing up for a little while and just now realized that two of the pins were completely bent and when I went to unbend one it just snapped off.
Is there maybe some other cable/device that may have the same shaped/sized connector?

But yes, that's what he is looking for.

They are not easy to get, as only Atari used them. However, many external devices have two ports for daisy-chaining. Since only one port is really needed, you could "borrow" one to repair the Atari.
Well it seems like a printable model of the casing should be simple enough (that link you provided, Chuck, would work). I guess I'd just need to get the pins.

Sent an email to Best Electronics, it'll be interesting to see if it goes through and/or if I get a response given the page hasn't been updated in a couple of decades.
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There are other schemes using a DA-15 D-sub connector, but that means replacing cables and doing a bit of hackwork. While a standard connector, I'm not sure that I like that approach.
There are other schemes using a DA-15 D-sub connector, but that means replacing cables and doing a bit of hackwork. While a standard connector, I'm not sure that I like that approach.
Yeah, I don't either. I'm wondering if I could just replace the broken pins with a paperclip or something. I mean the port is pretty much useless right now so not like I can make it worse.
Pin size and finish is important. You might consider scavenging from an old connector with the same pin size. Heaven knows I've done it with IDC male headers, rather than unsolder the old one.
I was able to get it fixed, I went though my stuff and found a few thermal fuses I had picked up a few years ago to fix a coffee maker. the legs on those were pretty much the same diameter as the SIO port pins.

So I opened up the computer, snipped off the back of the pin, pushed it out the front of the socket, pushed the leg of the fuse in and soldered it to the remaining back part of the pin just where it bends down and goes into the board.

If anyone stumbles on this post later and wants to make a whole new SIO port from scratch: https://3d.odkaznik.cz/sio-m
that link was on that printables link you posted ealier, it has not only the STL's but also the gerbers for the circuit board and a mouser part # for the pins.

Oh also did get an email back from Best Electronics so guess they're still around and they have some inexpensive options as well probably cheaper (and easier) than building from scratch.
Best Electronics is alive and well and in their 39th year ... I just got a bunch of parts from them. SIO port does not seem like an impossible thing to get. You might have to purchase the whole board, which for the price may be worth it vd the effort to decoder and resider a new port connector. Give them a try. best-electronics.com
The guy running it it a bit eccentric, but highly knowledgeable. I got my stuff in 2 days from California to New York. Great overall service. I just wish he would update the layout of his web site as it's in a state that was written in 1993 era web design and navigation is a nightmare. However, if you get a nice hot cup a coffee and some free time, you will find loads and loads of useful tips, tricks and trivia knowledge sprinkled all over the web site. Example - he goes into the CX40 joystick design, the various incarnations, does to the style of trees on the PCB nd the style contact dimples used .. like really really deep into nuances of just about everything. Yes Electronics also has gone out of their way to engineer and improve some of the Original Atari designs.... I'm impressed !