[Coco] CoCo 3 Voltage Regulator heat sink

[Tim Fadden]

Gene Heskett wrote:
> On Thursday 09 April 2009, Rick Taylor wrote:
>   
>> I had found a heat sink in a box - it's something I pulled out of an old
>> switching power supply, I think, maybe 3.5 inches square aluminum with fins.
>> I have it vertically mounted, seems to be adequate, but barely.
>> Incidentally, while putting the thing vertical, I applied a bit too much
>> torque and crunched the D880. I went to Jameco (with the mobo) and picked up
>> these at their will call counter, with a little help from them figuring out
>> what to use
>>
>> <
>> http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&sto
>> reId=10001&catalogId=10001&productId=33048&
>>
>>
>> I'm running it off a 200W AT style power supply. It's getting fairly toasty
>> but it's been running for about an hour and nothing's caught on fire yet
>>
>> :-)
>>
>> You can hold on to it for about three seconds before you go "wow! that's
>> hot!" and let go. I'm not particularly good with electronics. What would be
>> a better replacement that might run cooler?
>>
>>     
>
> If you have the schematics, its not too hard to just toss the heat sink & 
> transistor, and hook the AT supply up to it directly.  I did that about 15 
> years ago for both the mpi and the coco3.  Without that coffee warmer, and 
> with a disto 2 meg ram kit + a 63C09 in the cpu socket, the half a watt the 
> gime warms up is about the sum total of the heat generated in mine.  With a 
> furniture blanket on top of it hiding a darkroom thermometer laying on the 
> grill above the memory, it will read 2F above the room after 24H of uptime.
>
> I used one of those auto part stores 4 wire connectors that I just replaced 
> yesterday because it was getting noisy.  Now I have a nice clean screen again.
>
> I also have an error 246 when I try to use the /p port since then, so I may 
> need to recheck my work.  The wires in the kit I used are heavier than the old 
> one had, and I was forced to leave off the ssnapon rf chock I'd used 
> originally and re-arrange the connections & maybe didn't get the + & 12 volts 
> connected correctly again.  The rest of the coco3 wouldn't care.
>
>
>   
>> On Sat, Apr 4, 2009 at 5:06 PM, Robert Gault
>>
>> <robert.gault at worldnet.att.net>wrote:
>>     
>>> N8WQ wrote:
>>>       
>>>> Well I have my new 40 pin pcb connector soldered on the motherboard at a
>>>> 90 degree angle and it is working great in saving me some space in my
>>>> mini tower case. My next project is to put the stupid voltage regulator
>>>> heat sink in the vertical mode. Right now it is in the horizontal "space
>>>> hog" mode. :)
>>>>
>>>> Has anybody on the list ever swapped out the heat sink with another
>>>> version?
>>>>
>>>> Alan Jones
>>>>         
>>> Not me, but I did add a fan to a Coco3 so that there was significant air
>>> flow through the case.
>>>
>>>
>>> --
>>> Coco mailing list
>>> Coco at maltedmedia.com
>>> http://five.pairlist.net/mailman/listinfo/coco
>>>       
>
>
>   
Ditto to that, If the PC PS is connected properly, the regulator is no 
longer needed, and everything runs cool as coolaid!  I did the same on 
my repack many years ago, and I run the coco 24hours/day 7days a week.

Tim Fadden