Skip to main content
Home▸ Forums▸ 68kMLA▸ SE/30 Nice and clean now...but still loud :( — #13
Post #13 by JDW
Source Forum68kMLA
CategoryHardware
Post DateMon, 18 Apr 2011 - 22:21
Original URLhttps://68kmla.org/bb/threads/se-30-nice-and-clean-now-but-still-loud.21945/
Post
I found the SE/30 schematics and found the fan is powered thru a 1/2 Watt, 4.7 ohm resistor -- that would dissipate less than 0.15 Watt, way below the resistor's rating.
What schematics? Apple, BOMARC or something else? I have searched and searched for SE/30 schematics through the years and the best I could find were a set of somewhat incomplete Apple schematics and relatively more complete set of BOMARC schematics. But as I mentioned before, my BOMARC schematic of the analog section is for the SE, not the SE/30. However, I must assume there are many similarities. And on the BOMARC SE schematic, it shows the chip I posted about before, the LB1660. And in that section it shows a 47-ohm resistance, but no 4.7-ohm. Furthermore, the Elina fan is show to be connected to the LB1660 via a diode on pin 5 and through another diode on pin 3 (diode cathode facing toward the LB1660).

Therefore, it would appear that you have some schematic I do not, in which case I would like to see what you have. Toward that end I will send you a PM with my email address so you can forward your schematic to me.

As to you question about the blower direction, the hot air on my SE/30 with the stock Elina blew OUT of the machine.

mp.ls