[R-390] R-390 Digest, Vol 68, Issue 12

[Richard Spargur]

Is the Autotune you are referring to the AN/TRD-1465 system used to remotely
tune R-390/URRs remotely?  The project name was "AUTOTUNE".  I believe only
11 of these systems were built and I would be supprised to see one had
survived.  I would like to know if any survived.  Sprocketed pully
wheels/gears were attached to the MC and KC change shafts and they were both
tuned by belt fed servo motors to a frequency sent via teletype.  Odd to see
work.  If not what type of autotune was this version.

Richard
K3UI

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Message: 7
Date: Mon, 21 Dec 2009 23:16:10 -0500
From: Paul Anderson <paul at pdq.com>
Subject: Re: [R-390] Autotune
To: Mark McNulty <noggie1999 at yahoo.ca>
Cc: r-390 at mailman.qth.net
Message-ID:
	<ee957a250912212016g5b0e82f5q2d4931d8830a8e38 at mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1

There are slip clutches on the inside of the autotune units that need
to turn free with the right amount of torque.  If the 50 year old
grease is not cleaned out, they will not turn free, and the motor will
tear up the line shaft pretty bad.

If you haven't already, take the KC and MC tuner units off the
chassis, soak them in appropriate solvent for awhile (I used kerosene
for more than a week each).  At least then, the clutch should turn
freely.

If you choose not to clean the old grease out of the tuning units,
then I strongly suggest not applying power.

You also want to make absolutely certain that the tuner turns without
any crunching whatsoever, as well, turning the lock pins slowly should
produce no grinding, hangup, or other signs of dirt in the mechanism.

As long as the end stop clutches can turn, then I don't think applying
power to the motor will hurt or break anything unless you plan to use
the tuning very much and don't lube it according to the manual.

It's a neat mechanism when it works!