Thread
Is using an external fan needed with a Mac Plus?
Your view of mechanical air replacement may be a tad jaundiced, perhaps from experience with clogged vents or the like? The SilenX IXP-34-08 Ixtrema fan that I have on the way is rated at 10cfm, or roughly 10 replacements of the internal air each minute. Even at half that throughput I suspect that few calories generated by the electronics will hang about for more than a moment, and the airflow's turbulence will prevent formation of any dead-spots anywhere inside the case.
Although the pudding has yet to be eaten—and I am prepared to experiment with directing the airstreams by judicious masking of the case vents—I have no fears about the outcome of forced ventilation. I am no stranger to airflow patterns, having spent four years at one time in the development of a method to produce high-activity dry yeast from compressed yeast, using air-lift dryers.
de
Although the pudding has yet to be eaten—and I am prepared to experiment with directing the airstreams by judicious masking of the case vents—I have no fears about the outcome of forced ventilation. I am no stranger to airflow patterns, having spent four years at one time in the development of a method to produce high-activity dry yeast from compressed yeast, using air-lift dryers.
de
equill - it's funny how I have to shift my brain every time I read your posts. It's like going from day to day conversation to all of a sudden reading some Dickens, or something. LOL - it's not a knock, just an observation. 
No offence taken. Be assured, though, that the relationship between my screen name, avatar and occupation is far from accidental. And the use of MacDraw for the avatar is also no accident.
de
de
Uh, right. I do not recommend masking any external vents. I mean to direct and maximize the cool air flow from the bottom vents in much the same way as the engineered Classic/II does (which by the way returns the vent to the handle area previously removed from the SE). Meaning using duct tape, or the like to cover the openings on the deck of the metal chassis for all but below the fan's mounting. Then likewise use duct tape to cover the back of the FDD to minimize airflow through it. Otherwise I am in complete agreement that there will be substantial turbulence inside the beasty to keep it cool.
That said, I still prefer fanless, blissful silence. I think the M0001 was brilliantly engineered and is as elegant a solution as Mr. Jobs demanded. My perspective as to its well-documented failures has more to do with sub-standard components for the design (presumably to to maximize profits). Either way, it's hard for me to imagine using my M0001 for such extended periods as to overwhelm its engineering resulting in accelerated failure. Of course most of my boards have been upgraded with the more robust parts recommended. As I have stated elsewhere, I have a late model Plus (1990) which was used extensively over the years, in a hot poorly ventilated office space for many hours at a time and has never once been in the shop for repairs.[/u]
I have read a rumor that Apple changed the design of the Mac Plus power supply at some point. When users began to install 4MB of RAM in the Plus, the power supply would overheat. Apple examined the issue and installed a better power supply in later Mac Plus units. Mac Plus computers with the second type of power supply were not as likely to overheat.
Is there any truth to this rumor? If there is, when did the change in power supply occur? My Plus has a date of 1988 on it.
--David
It could be Mac128 has had success without active cooling because his Mac Plus was manufactured later in the production run. Perhaps only the earlier Mac Plus computers with the inferior power supplies require active cooling to prevent overheating.
Is there any truth to this rumor? If there is, when did the change in power supply occur? My Plus has a date of 1988 on it.
--David
David, it would be VERY helpful if you could open your Plus, remove the analog board and shoot some photos for us. Seeing the numbers on the analog board is what we're mainly after, although I wouldn't mind seeing the flyback and other components used on your board.
You can see my analog board photos here.
You can see my analog board photos here.
Here's the one I built back around 1990:
http://www.io.com/~trag/Chimney/Chimney0.JPG
http://www.io.com/~trag/Chimney/Chimney1.JPG
http://www.io.com/~trag/Chimney/Chimney2.JPG
http://www.io.com/~trag/Chimney/Chimney3.JPG
It'snot the professionally die cut one, but it worked for several years.
trag, LOL, I LOVE that! I had seen that picture on the net before ... now I know it was you! It's like some kind of Wizard of Oz Mac.
JDW & dbraverman88, I had posted my analogue board info here: http://68kmla.org/forums/viewtopic.php?p=26919#26919
The 820- numbers are the key, not the 630- numbers. It would appear that Apple figured out real quick they needed to update the board (if that's the case) as my June, 1990 "820-E" board is copyright 1986. This is clearly the last US domestic 120v analogue board produced since the Plus was discontinued in October 1990. JDW, it would be great to get the 820- number from under your 661-0462 replacement board's vinyl cover, since yours should be the late model also and identical to mine based on its 630- number. You already have the B & C boards, so all I may need to do is cover the "D" board pictorially since I think you have the E. We need to get stevep to document his late model International board more thoroughly as well.
JDW, with your existing Excel spreadsheet data and pictures from the missing "D" board from your collection, excluding any undocumented modifications, you should be able to catalogue an extremely specific and detailed upgrade history for the M0001 analogue board components.
JDW & dbraverman88, I had posted my analogue board info here: http://68kmla.org/forums/viewtopic.php?p=26919#26919
The 820- numbers are the key, not the 630- numbers. It would appear that Apple figured out real quick they needed to update the board (if that's the case) as my June, 1990 "820-E" board is copyright 1986. This is clearly the last US domestic 120v analogue board produced since the Plus was discontinued in October 1990. JDW, it would be great to get the 820- number from under your 661-0462 replacement board's vinyl cover, since yours should be the late model also and identical to mine based on its 630- number. You already have the B & C boards, so all I may need to do is cover the "D" board pictorially since I think you have the E. We need to get stevep to document his late model International board more thoroughly as well.
JDW, with your existing Excel spreadsheet data and pictures from the missing "D" board from your collection, excluding any undocumented modifications, you should be able to catalogue an extremely specific and detailed upgrade history for the M0001 analogue board components.
I have not done an exhaustive tracking of what was changed over time (but I suspect JDW has, and will chime in shortly). I do know that the flyback was upgraded fairly early on, so incidents of HV failure dropped quite a bit. However, the yoke connector problem (triggered by heat) was pretty much a constant over the life of the Plus. The basic switching supply topology did not change (AFAIK), and there were no component upgrades that made much of a difference in efficiency. So, the amount of heat produced likely remained constant. Improvements in longevity mainly came from component upgrades aimed at reducing their sensitivity to the heat.
If JDW (or anyone else) has specific knowledge of power supply changes during the life of the Plus, I'd love to hear from them.
I gave some nice fellow permission to use the pictures in an article on heat disposal that he wrote for (IIRC) IBM's website. You may have seen them there. Unfortunately, I can't remember who the fellow was. I don't really need to know. It's just kind of disheartening to have a friendly exchange with someone and then a few years later you have no idea who it was....
I really need to get back to this. I have been busy with other things. I will take it apart and shoot those pictures as soon as I can.
--David
I added a fan to my iMac 350MHz and it was blowing on the logic board(the other side where the HD and disk drive are located) and it worked just fine. I added an ATX drive cable expander to the existing ATX cable inside and it worked just fine. Not sure if the older macs have the regular ATX connections but its worth a try.
No one has a copy of the Chilton's Guide?
I am interested in knowing how it compares to what Larry Pina wrote. If I were back in the states, I would check it out at my local library in a heartbeat, but I can't do that from Japan.
So if any of you know of this book, do tell!
Thanks.
I am interested in knowing how it compares to what Larry Pina wrote. If I were back in the states, I would check it out at my local library in a heartbeat, but I can't do that from Japan.
So if any of you know of this book, do tell!
Thanks.
Isn't Chilton the guide typically associated with automobile repair? I remember using one at the library many years ago to diagnose a problem with our family's 1985 Honda Accord so we could explain it to a mechanic who was looking at buying the car (which we opted to replace instead of repair due to its age).
Back in early 1984, I haven't the faintest idea if they also covered automobiles. But here is an actual auction for the "Macintosh" book I am talking about:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=180155335235
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=180155335235
I have a Kensington System Saver Mac and the fan is pretty quiet. Most times I wouldn't notice it running. When I first got the unit I had a bit of bearing noise at first but after lubing it that quietened down. I don't know if it has the original fan or not. If yours is unpleasantly noisy then I'd probably shop for a replacement fan.
Wayne
Wayne