Jump to content
Sign in to follow this  
Atarileaf

Atari Heavy Sixer Ribbon Problem

Recommended Posts

I was given this heavy sixer which I was told was dead and noticed the ribbon cable is in very poor condition. I get a black screen when it's powered on and am thinking there's a good chance it's this ribbon cable. It seems to be separating which would lead me to believe there's poor or no communication between the two boards. Any advice on this and possible replacements?

 

 

post-92-0-40638700-1515885577_thumb.jpg

Share this post


Link to post
Share on other sites

I was given this heavy sixer which I was told was dead and noticed the ribbon cable is in very poor condition. I get a black screen when it's powered on and am thinking there's a good chance it's this ribbon cable. It seems to be separating which would lead me to believe there's poor or no communication between the two boards. Any advice on this and possible replacements?

 

You can verify the ribbon cable with the continuity check setting on a multimeter and test each line in turn while giving the cable a bit of a wiggle. While you're at it you should then test continuity between power and ground rails, to ensure there are no shorts present, and then power it on and check your voltages on power rails and on pin at various chips.

Share this post


Link to post
Share on other sites

Thanks for the reply. I'll check continuity on these tomorrow. In the event it's toast, is something like this repairable and if not, are there replacements for these without cannibalizing another machine? This is the first one I've seen with a mylar style ribbon, my other heavy/light sixers use a regular wire cable. These mylar ribbons seem problematic at best and a generally poor design.

Edited by Atarileaf

Share this post


Link to post
Share on other sites

If it is the ribbon, replacing it with wires is going to be your best bet.  You should be able to find connectors for the end of each wire that fit into the slot for each wire. 

But my guess is that it isn't the ribbon...if it was, how would the unit even turn on?

Share this post


Link to post
Share on other sites

So I seem to be getting continuity with all the pins where the ribbon cable is soldered in place to the various spots on the board each pin leads to and they all seem to check out. I'm getting the beeps. So it's possible the ribbon cable itself is fine and the plastic on both sides is simply separating?

 

As for power to ground rails, I'm not sure what that means. The power jack where the psu plugs into? What are the ground rails. Sorry I'm still fairly new to this and I'm not overly familiar with the terminology. The power jack itself seems to get continuity to those same points on the board to that ribbon cable so I think it's alright.

 

BTW I checked the voltage regulator again with the machine powered on and I'm getting 8.5v in and 6.3 out and the heat shield around it is pretty hot to the touch. That sounds out of spec that should be replaced?

Edited by Atarileaf

Share this post


Link to post
Share on other sites

So I seem to be getting continuity with all the pins where the ribbon cable is soldered in place to the various spots on the board each pin leads to and they all seem to check out. I'm getting the beeps. So it's possible the ribbon cable itself is fine and the plastic on both sides is simply separating?

 

Yeah, that's what it's sounding like. Although if you're feeling brave it may not be a bad idea to follow up on RiskR's suggestion to swap it out for something a little more durable.

 

As for power to ground rails, I'm not sure what that means. The power jack where the psu plugs into? What are the ground rails. Sorry I'm still fairly new to this and I'm not overly familiar with the terminology. The power jack itself seems to get continuity to those same points on the board to that ribbon cable so I think it's alright.

 

No worries. :) Ground on the Stella just means the 0v pin on the regulator. Ordinarily, you shouldn't see any continuity between the 5v and GND, unless ...

 

 

BTW I checked the voltage regulator again with the machine powered on and I'm getting 8.5v in and 6.3 out and the heat shield around it is pretty hot to the touch. That sounds out of spec that should be replaced?

 

... there's some kind of short between them? It may not be the regulator is failing, but a failing capacitor on the board somewhere which is causing a mild short. That's pretty typical in older electronics and would explain the regulator's behaviour. Whatever the cause, you're right, those are very suspect readings!

Share this post


Link to post
Share on other sites

Thanks for the help I really appreciate it :)

 

So I'll try to find a suspect capacitor. Should I just follow the board traces between the power jack and the regulator and see if I find any suspect readings on the various caps along that path?

 

BTW I do have an old intellivision parts machine with a voltage regulator that's giving me 12.5v in and 5.1 out. It's a standard 7805. If I don't find any bad caps I suppose I could swap out the regulator on the atari for this one? I may also order a dozen or so from console5. That's a great site with very helpful people.

 

Also would a bad voltage regulator cause black screen issues?

Edited by Atarileaf

Share this post


Link to post
Share on other sites

You could swap it out.  But I'd buy a new one.  They are super cheap.  Look on ebay.

 

It would cause black screen issues.  Unfortunately, the higher voltage *may" have taken a chip or two out with it.  But try changing the regulator out and see if it works.  In many cases, it does. 

Share this post


Link to post
Share on other sites

You could swap it out.  But I'd buy a new one.  They are super cheap.  Look on ebay.

 

It would cause black screen issues.  Unfortunately, the higher voltage *may" have taken a chip or two out with it.  But try changing the regulator out and see if it works.  In many cases, it does. 

 

Will do thanks Rick.  I'll put that order in at console 5. Yes my concern is that some chips went too but fingers crossed. I'll post again when the voltage regulators arrive and I swap them out. Maybe I'll grab a refresh kit while I'm at it.

Share this post


Link to post
Share on other sites

Will do thanks Rick.  I'll put that order in at console 5. Yes my concern is that some chips went too but fingers crossed. I'll post again when the voltage regulators arrive and I swap them out. Maybe I'll grab a refresh kit while I'm at it.

I would just grab the refresh kit and replace everything from the kit. Comes with a new 7805 of higher quality over the original, new caps, and a new switchcraft powerjack if I remember correctly. Those refresh kits are great and I've used them on just about all of my 2600s I have on hand and always on ones that I give away to friends and relatives or sell. For $10 it is cheap insurance in a plastic baggie!

Share this post


Link to post
Share on other sites

I did actually. I went on a bit of a shopping spree - got a 2600 refresh kit, a 7800 refresh kit, 10 7805 voltage regulators, a couple of ferrite chokes, a couple tubes of thermal paste, and some 7800 console buttons. I like the idea of keeping a lot of the common parts around for various projects. I'm thinking of placing an order with Best as well for a couple each of the TIA, Riot and 6507. I wonder if he sells the appropriate sockets as well. I may need to replace the actual sockets on this machine too.

Share this post


Link to post
Share on other sites

I have a question about sockets. In looking online to purchase some, there seems to be different widths. I'm pretty sure I need the wider ones but some list things about having round pins as opposed to not. The only thing I know for sure is that I need 40 pin and 24 pin sockets for the 2600. Other than that I need a little guidance. For instance this listing on amazon canada

 

https://www.amazon.ca/uxcell%C2%AE-2-54mm-Double-Socket-Adapter/dp/B00O9YQSUO/ref=sr_1_2?ie=UTF8&qid=1517830747&sr=8-2&keywords=40+pin+ic+sockets

 

shows round pins but this listing for 24 pin sockets doesn't

 

https://www.amazon.ca/Pieces-2-54mm-24-Pin-Socket-Adapter/dp/B00OK5YOGC/ref=sr_1_2?s=electronics&ie=UTF8&qid=1517830813&sr=1-2&keywords=24+pin+ic+sockets

 

A close up of both shows small round bases on each pin underneath the 40 pin listing and the top where you insert the chip is round but the 24 pin listing shows the pin without this little base and a different top where you insert the chip. The second one looks more like the ones I've seen in atari's before. Is one better than the other or does it even matter?

 

Thanks

Edited by Atarileaf

Share this post


Link to post
Share on other sites

I have a question about sockets. In looking online to purchase some, there seems to be different widths. I'm pretty sure I need the wider ones but some list things about having round pins as opposed to not. The only thing I know for sure is that I need 40 pin and 24 pin sockets for the 2600. Other than that I need a little guidance. For instance this listing on amazon canada

 

https://www.amazon.ca/uxcell%C2%AE-2-54mm-Double-Socket-Adapter/dp/B00O9YQSUO/ref=sr_1_2?ie=UTF8&qid=1517830747&sr=8-2&keywords=40+pin+ic+sockets

 

shows round pins but this listing for 24 pin sockets doesn't

 

https://www.amazon.ca/Pieces-2-54mm-24-Pin-Socket-Adapter/dp/B00OK5YOGC/ref=sr_1_2?s=electronics&ie=UTF8&qid=1517830813&sr=1-2&keywords=24+pin+ic+sockets

 

A close up of both shows small round bases on each pin underneath the 40 pin listing and the top where you insert the chip is round but the 24 pin listing shows the pin without this little base and a different top where you insert the chip. The second one looks more like the ones I've seen in atari's before. Is one better than the other or does it even matter?

 

Thanks

 

I actually answered this just now in the Hardware forum at AA. But the top ones are called machine pin type sockets are are best used with IC or devices that have round peg like legs on them. While could use standard thin IC legs in the round sockets, they only make contact with just the thin edge of the legs of the IC doing so. Much better to go with the bottom ones you listed. Those are called dual wipe sockets and are designed for the standard thin legs that most ICs use. They have much better surface contact on both sides of the legs inside and out.

Share this post


Link to post
Share on other sites

I actually answered this just now in the Hardware forum at AA. But the top ones are called machine pin type sockets are are best used with IC or devices that have round peg like legs on them. While could use standard thin IC legs in the round sockets, they only make contact with just the thin edge of the legs of the IC doing so. Much better to go with the bottom ones you listed. Those are called dual wipe sockets and are designed for the standard thin legs that most ICs use. They have much better surface contact on both sides of the legs inside and out.

 

Thanks very much. That makes sense I believe the ones in a 2600 are also the ones in the second link. I'll look for those thanks :)

Share this post


Link to post
Share on other sites

Cross posted from Atariage for any hardware experts here

 

So I'm worried I destroyed this board. I have to desolder the sockets for all 3 of the main IC's since the sockets broke off trying to remove the chips with a chip puller. I use my iron and desoldering braid but I may have damaged the board in the process. I still can't get some of the legs out even though the solder is gone from each hole. I hope I didn't but fear I did. Break it to me gently.

 

My concern with the third pic is I stupidly used a screwdriver to pry up the chip when I originally couldn't find my chip puller and scratched some traces

 

 

post-92-0-67021500-1518299828_thumb.jpg

post-92-0-44470900-1518299840_thumb.jpg

post-92-0-45568800-1518300663_thumb.jpg

Edited by Atarileaf

Share this post


Link to post
Share on other sites

Cross posted from Atariage for any hardware experts here

 

So I'm worried I destroyed this board. I have to desolder the sockets for all 3 of the main IC's since the sockets broke off trying to remove the chips with a chip puller. I use my iron and desoldering braid but I may have damaged the board in the process. I still can't get some of the legs out even though the solder is gone from each hole. I hope I didn't but fear I did. Break it to me gently.

 

My concern with the third pic is I stupidly used a screwdriver to pry up the chip when I originally couldn't find my chip puller and scratched some traces

 

Ouch, the poor board! ;) Don't worry though, nothing a little TLC won't take care of.

 

A few comments:

 

1) Despite the scratches on the soldermask I think the traces beneath are still intact, although it's hard to tell with some of the light glare. Do a continuity test to make sure. If you're feeling a bit brave there are compounds you can get for filling in soldermask pretty cheaply.

 

2) Do you have a temperature control on your soldering iron? A lot of the grunginess looks like burning from excess heat, possibly from the iron being applied for too long. Aside from the aesthetics this can be a bit of a concern because too much heat will remove the solder pads from the board, which is a very tricky thing to repair. Make sure you're using a solder tip which you're comfortable controlling the amount of heat transfer so you're not having to apply it for too long. On these older boards the solder alloy has a lower melting point than modern solder (more lead ;) ) so a soft touch is all you need.

 

3) When you remount the chips use a socket mount instead. That way if you do make a mistake you you're only risking a cheap 50c part and make repairs down the line easier when you need to swap ICs in and out.

 

4) You should probably clean those pads with a touch of alcohol, to get some of the burn smear off, and then re-tin each pad (make sure you're using flux!) before attempting to solder onto them again. Also, a touch of flux on your solder braid will work wonders too.

 

5) Regarding the holes with legs still stuck: there's still solder inside the hole which is just enough to keep it stuck. Don't force it! Turn the board on its side, apply heat gently from one side and just push through something like a resistor leg from the other side to eject the fragment.

 

6) As I think about the last point it also occurs that you may not have good lighting and magnification available? Both will save you a lot of hassle as you'll see things you wouldn't otherwise.

Edited by dgrubb

Share this post


Link to post
Share on other sites

What dgrubb said. Also if you aren't already, you need to actually add a bit of fresh solder to a joint before trying to remove it. This helps breakdown the corrosion on the old solder that can make it holds it shape a bit more than you want and not make it wet properly for removal. Also you will need to get a basic meter and check the continuity between those pins and where the traces look to go on the next nearest component. If any are broken, you can use speaker wire a.k.a. kynar wire to solder to the pad where the trace is suppose to go to and to the leg of the component that it came from. I've had to do this a few times when corrosion from old batteries or when a solder pad has come loose on me while working on stuff. 

 

I will say that a decent de-soldering station is a must for anyone that will be doing lots of this kind of work. I didn't use one of years and when I finally got one for father's day several years back, well...it has made a HUGE world of difference!

Share this post


Link to post
Share on other sites

Forgot to add a few more things about this.

 

when you do get those traces repaired if any are broken, then the areas where you scraped off the solder mask, you need to use some clear nail polish or super clue to coat over the exposed traces. If you don't you leave the copper open to corrosion and that will lead to more issues down the line. I actually just use a thin coat of solder ontop of exposed traces as long as there isn't a risk of anything shorting across it. 

 

Anytime you are de-soldering something and you remove the solder and it doesn't come free easily, you need to add more solder and try and remove it again. For really stubborn old joints I usually add a bit of solder to the top and bottom of board where the component goes through to make sure it all mixes in well before I try and remove it.

 

De-soldering ICs isn't the easiest thing so these things happen. Just be patient and methodical about it and you will get better over time. For practice, pick up old electronics from computer stores tossing out stuff that aren't recycling it properly, or hit up your local thrift stores for cheap older electronics like old radios and the like that obviously look like they won't work for a couple of bucks. Good way to get the experience you need without feeling bad about butchering it up, and you will likely salvage some parts you might just need in the future.

 

Also this is what I do to fix these old ribbon cables that start to come apart. And you really should replace it or do something about it, because the inner traces could potentially short against each other if you were to bump it while it was on. There is voltage in those traces going to the main logic in the fear cage box that it hides in. Funny thing here is that I actually machine pin headers for this. Also this repair was on an Intellivision I fixed for someone else as they had hosed up the ribbon cable pretty badly in trying to do their own repairs.

 

post-1236-0-36160900-1518464839_thumb.jpg

Edited by CrossBow

Share this post


Link to post
Share on other sites

Thanks for the advice guys. I do have a Hakko soldering station with digital controls. What is the temperature in Celcius I should set it at? And you're right I probably did have the iron on too long on some of those spots. A solder sucker wasn't working so I tried desoldering braid after applying some liquid flux to the board. I was still having trouble for some reason. My station was set to 600C I believe. The tip was tinned and working but I still had a hard time removing some of those solder points. Some came quick, others didn't. You can probably tell the ones I struggled with :)

Share this post


Link to post
Share on other sites

600c is too hot for most board work. I usually have my Hakko 936 set between 350 - 400c for most work. On the Colecovision I actually keep it at 280 - 300 thereabouts. The CV uses a lot of leaded solder and is melts easier. Unfortunately, so do the contact pads and traces...

 

I will occasionally put the iron at around 700 - 750 if I have to solder something on a large trace that is likely ground. That is because the larger the surface area you are attaching to, the more heat is needed since the larger area will 'sink' the heat away and prevent the solder from sticking to the pads where it is needed.

 

One way you know you iron is likely too hot, is when the solder sticks to the iron more than it will what the solder should be adhering to.

Share this post


Link to post
Share on other sites

 My station was set to 600C I believe.

 

:o

 

I usually keep mine at around 350C, and even that may be a little high for the older solder alloys used in the late-70s.

 

For practice, pick up old electronics

 

This is sound advice, especially with the anxiety this has been causing you recently.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×