I found this thread from 4 years ago. I'll give it a try...
http://www.classiccmp.org/mail-archive/classiccmp/1998-09/0953.html
From: "R. D. Davis" <rdd(a)rddavis.org>
Reply-To: cctalk(a)classiccmp.org
To: cctalk(a)classiccmp.org
Subject: Re: PDP11/44 update, dead wierd fan (35VAC, 75Hz)
Date: Wed, 18 Dec 2002 22:06:28 -0500
What you don't need is a replacement fan. :-) I had a similar problem
when I got my 11/44 several years ago; Tony Duell kindly instructed me
on the _proper_ way to solve this problem.
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