lenny@icus.UUCP (Lenny Tropiano) (01/28/88)
This morning (1:00am) my machine died ... it turned of, rebooted, off,
rebooted, off (continuously). As I quickly found out the fan in the back
that keeps the unit fairly cool had died. This is pretty common, as I
found out in UNIX PC's. The company I work for (an AT&T VAR) has had
to call AT&T a couple of times on "death-of-a-fan" problems.
Well I was luckier than most, I was their when the machine actually
crashed, so I quickly shut the power off by the switch and let the system
cool. If this up-and-down sequence continues too long, you generally have
hard disk problems. Also, if it gets too hot, I assume the motherboard will
have problems.
Now I called my friendly neighborhood AT&T tech, and asked him how much
a new fan would cost (since I don't have a maintenance contract), he
looked it up and said, "Hmmm, Fan Assembly, that will run $100 for the
parts plus labor". Uhhh, I choked. Well as it turns out the fan inside
the UNIX PC is a 12 volt DC 3" fan. I went down to my neighborhood
Radio Shack, and picked up:
Cat. No. 273-243 3" (80mm) DC Brushless fan $14.95
I went home, got a phillips screwdriver and started attacking it! To
do the whole procedure took about 25 minutes, and the machine is up
and running (still very cool after 3 hours). I bought two fans,
my next project is to remove the foam in the left side and replace that
with another fan. (Hey, what's a little more hum?) :-) I'll keep everyone
posted. I might just use that user controlled LED on the left side to
turn it on and off at periods of time... Who knows?
-Lenny
--
============================ US MAIL: Lenny Tropiano, ICUS Computer Group
IIIII CCC U U SSSS PO Box 1
I C C U U S Islip Terrace, New York 11752
I C U U SSS PHONE: (516) 968-8576 [H] (516) 582-5525 [W]
I C C U U S AT&T MAIL: ...attmail!icus!lenny TELEX: 154232428
IIIII CCC UUU SSSS UUCP:
============================ ...{uunet!godfre, harvard!talcott}!\
...{ihnp4, boulder, mtune, bc-cis, ptsfa, sbcs}! >icus!lenny
"Usenet the final frontier" ...{cmcl2!phri, hoptoad}!dasys1!/lenny@icus.UUCP (Lenny Tropiano) (01/29/88)
In article <234@icus.UUCP> lenny@icus.UUCP (Lenny Tropiano) [That's me] writes: |> |> |> [description about installing a stock Radio Shack Fan] |> |> Cat. No. 273-243 3" (80mm) DC Brushless fan $14.95 |> |>I bought two fans, my next project is to remove the foam in the left side |>and replace that with another fan. (Hey, what's a little more hum?) :-) |>I'll keep everyone posted. I might just use that user controlled LED on the |>left side to turn it on and off at periods of time... Who knows? |> I noticed a slight problem after installing the 1st fan. I had the fan in backwards, so instead of blowing the air out, it was sucking it in. This keep the power supply pretty cool, but the front of the UNIX PC was getting warm (abnormally warm). Make sure if you install the fans that they are blowing out the back (Radio Shack label facing grill in back). Since I had the PC open again, I took this opportunity to install the second fan. I didn't get fancy and make it controllable by the LED. The noise is so minimal I though it might as well be on all the time. The brushless fans have a very low noise output. I just tied the two fans together keeping the polarity the same, and wha-la! Now the system seems to be moving air out very nicely! Why didn't they stick with the two fans like the older PC7300's? Oh well! -Lenny -- ============================ US MAIL: Lenny Tropiano, ICUS Computer Group IIIII CCC U U SSSS PO Box 1 I C C U U S Islip Terrace, New York 11752 I C U U SSS PHONE: (516) 968-8576 [H] (516) 582-5525 [W] I C C U U S AT&T MAIL: ...attmail!icus!lenny TELEX: 154232428 IIIII CCC UUU SSSS UUCP: ============================ ...{uunet!godfre, harvard!talcott}!\ ...{ihnp4, boulder, mtune, bc-cis, ptsfa, sbcs}! >icus!lenny "Usenet the final frontier" ...{cmcl2!phri, hoptoad}!dasys1!/
kai@ihlpa.ATT.COM (Irwin) (01/29/88)
In article <234@icus.UUCP>, lenny@icus.UUCP (Lenny Tropiano) writes: > [...] > > the UNIX PC is a 12 volt DC 3" fan. I went down to my neighborhood > Radio Shack, and picked up: > > Cat. No. 273-243 3" (80mm) DC Brushless fan $14.95 > > I went home, got a phillips screwdriver and started attacking it! To > do the whole procedure took about 25 minutes, and the machine is up > and running (still very cool after 3 hours). I bought two fans, > my next project is to remove the foam in the left side and replace that > with another fan. (Hey, what's a little more hum?) :-) I'll keep everyone > posted. I might just use that user controlled LED on the left side to > turn it on and off at periods of time... Who knows? > -- > ============================ US MAIL: Lenny Tropiano, ICUS Computer Group > ...{ihnp4, boulder, mtune, bc-cis, ptsfa, sbcs}! >icus!lenny The original 7300s had two fans mounted, thats the reason for the extra vent (original 7300s had "7300" on the monitor bezel, not "UNIX PC"). 3" 12volt roller bearing fans are pretty quiet compared to the non-roller bearing type that comes in a UNIX PC, so two roller bearing fans have about the same amount of "hum" as one non-roller type of the same CFM. I would just wire them up to be on all the time, so if one goes you still have one left, just make sure you make a habit of putting the keyboard back in its place in front of the floppy (the "other" fan tends to suck quite a bit of dust through the floppy drive, soaking up the oil on the guides for the head assy. and you have to take the top off to relube these, not something you want to do a lot on a UNIX-PC, ease of service was not a high priority in the design) just a little tidbit for UNIX PC owners, when the display seems to lose hor. sync. or roll (a common problem on these machines) take off the top, clean and bend down the copper grounding contact connected to the monitor base, about 95% of the time this is the only problem (bad grounding). Ken A. Irwin AT&T Bell Labs, Naperville IHP 1A332 (312) 416-4485 ...!ihlpa!kai