[ARC5] A hardly relaxing oscillator

[Brian]

Hello Dave,

We have talked about this before.

Giving all the screws a little tweak may solve a present problem, by biting 
through an electrolytic corrosion cell that has developed between aluminium 
(chassis), steel (lock washer) and brass (screw). If you or your inheritors 
continue to give little tweaks, the screw will eventually break.

The better, and more permanent solution is to remove each screw, dunk it in 
Almanox (or similar conductive, anti-corrosive grease) and then return it, 
tightening it to its required torque. If the set has had an inadvertent 
swim, remove the screws, clean between the pieces (ie, remove any corrosion) 
being held together and then apply a smear of Almanox.

73 de Brian, VK2GCE.

On Tuesday, February 03, 2015 3:12 AM , Dave said:

<snip> If the receiver is motorboating, two most likely suspects are either 
a bypass cap open or, more and more common, you have a Hi-Z ground point 
somewhere.  Any chassis connection or screw is suspect.  In the last 5 years 
I have cured many  problems by finding every screw or binder that grounds 
something to the chassis by giving it a little "tweek." Last one was weak 
receive in a Mackey Marine receiver.  It was the screws fastening the front 
panel.  I normally go over all such screws and bolts first thing but forgot 
these.  One fractional tweek and the problem was cured.