Installing a laptop fan

[+doctorclu]

I have a 800 running Incogneto, which I believe the Pokey and PIA chips, recently installed straight from the blister pack, are running hot after about thirty minutes. I get gibberish while running Ice-T after a bit, and that is where we believe the Pokey or PIA are running hot.

 

I have a laptop fan that runs at DC 5V .8w. Does the 800 have any extra power from it's power supply that could handle this fan (which I intend to run over the Pokey and PIA to keep it cool). If so, where could you tap into the power?

Edited January 22, 2014 by doctorclu

[+Larry]

What power supply are you using currently?

 

-Larry

[+doctorclu]

Ok this is weird, Larry this question earlier this morning, and then there was this...:

 

Justin Payne has just posted a reply to a topic that you have subscribed to titled "Installing a laptop fan".
How hot are those chips running at? People put heatsinks on the Raspberry Pi CPUs and it doesn't run hot enough to need one. Thats the reason why I ask.

 

---------

 

Well Larry, regular power supply. Justin, I'm liking the heat sink idea. Got me thinking.

[+Larry]

Evidently a server crash at AA. Error 403 this afternoon... I had several posts this AM and all gone this PM, so I re-posted.

 

Atari had at least two 9 VAC power supplies, and I think it actually was three. What is the VA of the one you are using -- 31?

 

-Larry

[+doctorclu]

Yes both I use are 31.

[+doctorclu]

Yes both I use are 31.

 

Was there any other information you needed Larry?

[+Larry]

Candle might be able to tell you if he thinks the Incognito pulls much of an additional load, and might also offer some guidance.

 

If you use a small (external) fan and blow air to the affected area, do things improve?

 

What kind of voltages are you getting inside the 800? If it were me, and the voltage is OK, I'd try the fan and see what your system voltage is before and after adding the fan (assuming that the air flow helps). If it does not drop significantly below 5 VDC, I'd think you are good to go. I've never really tinkered much with 800's, so I don't know if there is any 12V inside. I doubt it, but don't know.

 

Atari did make a bigger 800 PS -- was sold at BEST, 50 Watt for $15 (just in case).

 

-Larry

[BillC]

Candle might be able to tell you if he thinks the Incognito pulls much of an additional load, and might also offer some guidance.

 

If you use a small (external) fan and blow air to the affected area, do things improve?

 

What kind of voltages are you getting inside the 800? If it were me, and the voltage is OK, I'd try the fan and see what your system voltage is before and after adding the fan (assuming that the air flow helps). If it does not drop significantly below 5 VDC, I'd think you are good to go. I've never really tinkered much with 800's, so I don't know if there is any 12V inside. I doubt it, but don't know.

 

Atari did make a bigger 800 PS -- was sold at BEST, 50 Watt for $15 (just in case).

 

-Larry

The 800 does have +12V and -5V as well, these are needed for the original 8K & 16K RAM cards. With the Incognito upgrade replacing these cards I believe the +12V supply is no longer used.

[Joey Z]

I don't know how much a fan will help you unless you drill some ventilation holes or slots in the RF shielding. Circulating the same air over and over again might not do much. Does it have the same problem with the shielding removed?

[candle]

if you think you need a fan, it's all in your head...

[+doctorclu]

I don't know how much a fan will help you unless you drill some ventilation holes or slots in the RF shielding. Circulating the same air over and over again might not do much. Does it have the same problem with the shielding removed?

 

Yes, I came to realize that too. Guess I'll have to play with this setup a bit more to iron out the bugs/gibberish in the serial communication that seem to be coming from overheating.

[flashjazzcat]

What you might have here is a thermally-related circuit fault rather than what you describe as overheating. Chips get warm; poor connections move and become discontinuous. Keeping them artificially cool only masks the real problem. When I had problems with hot ICs, it was a continuity tester and soldering iron which solved them, not a cooling fan.

[+Stephen]

Is there a legit reason why any chip in the Atari would get that warm though? I've certainly never felt anything in my machine that I would describe as hot - let alone consider using a heatsink on.

[Kyle22]

Some of the Atari chips do get warm. They shouldn't be burning hot, though. Over the years, the heating and cooling cycle causes expansion / contraction which sometimes works the chips loose in their sockets.

 

try (gently, but firmly) pushing all the chips down in their sockets.

[+doctorclu]

What you might have here is a thermally-related circuit fault rather than what you describe as overheating. Chips get warm; poor connections move and become discontinuous. Keeping them artificially cool only masks the real problem. When I had problems with hot ICs, it was a continuity tester and soldering iron which solved them, not a cooling fan.

 

So you are thinking I have a bad solder point. That is possible. I'll go over the points and make sure all is well connected.

And press on the chips and make sure they are firmly connected, which I generally tend to do anyway, but I'll give it another go.

[+Larry]

if you think you need a fan, it's all in your head...

 

Clever!

[flashjazzcat]

So Pokey and PIA are brand new: along with Incognito, these are the variables. Simlply replacing the ICs could have fractured tin in the machine sockets, for example... these are the suspects I'd look at first, personally at least.

[+doctorclu]

 

Clever!

 

Clever? I honestly thought it was rude, but didn't answer since it didn't help with the conversation.

[+doctorclu]

So Pokey and PIA are brand new: along with Incognito, these are the variables. Simlply replacing the ICs could have fractured tin in the machine sockets, for example... these are the suspects I'd look at first, personally at least.

 

I checked out the solder points last night and if that doesn't work I'll check out the sockets. Thanks!

[+Larry]

That was my first reaction, then (I think) I saw the intended humor.

 

What is your handle -- doctorclu. "It's all in your head." So I took it as a pun from your handle.

 

-Larry

[flashjazzcat]

Ah right: I went to the extreme lengths of enrolling a second party to try and detect the pun or humour in that post, but we both missed the doctor reference, if it was intended.

[+doctorclu]

Ah right: I went to the extreme lengths of enrolling a second party to try and detect the pun or humour in that post, but we both missed the doctor reference, if it was intended.

 

Thanks for that observation but in the end not important. Just trying to narrow down the factors to make the serial communication more stable since BBSing is my hobby, and so is Atari.

 

Bad solder point, bad continuity, bad socket, all good suggestions to look at. Thanks all for those.

[Osgeld]

I don't know how much a fan will help you unless you drill some ventilation holes or slots in the RF shielding. Circulating the same air over and over again might not do much.

 

surprisingly enough I bet its enough to drop 5-10c, recirculating hot air is better than letting it do its own thing in an enclosed space, though not ideal

 

(cause your taking hot spots and moving it around non hot spots meaning the surface area of the enclosed space is greater than just letting a single spot heat up)

Edited January 26, 2014 by Osgeld

[+Larry]

So does your Incognito feel any better? Did you try a fan or some other type of ventilation?

 

-Larry

[flashjazzcat]

Just trying to narrow down the factors to make the serial communication more stable since BBSing is my hobby, and so is Atari.

Appreciated. Fan not the answer. This:

 

if you think you need a fan, it's all in your head...

It helps greatly with the conversation because you don't need a fan.

Edited February 9, 2014 by flashjazzcat