[Coco] CoCo 3 Voltage Regulator heat sink

[Gene Heskett]

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


-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Yow!  Are we laid back yet?