Airframe as Return Leg of Electrical Circuits

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Dan Thomas

Well-Known Member
Joined
Sep 17, 2008
Messages
5,251
One use of (of a particular variation specific for high voltage insulating sealant) was in TV repair shops, back in the dark ages when the picture was displayed on something called a 'tube'.

Charlie
I remember those. Got my share of shocks off them too while fixing the TVs.

Those were the days. When consumer-grade electronic stuff was repairable. No more.
 

rv7charlie

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Joined
Nov 17, 2014
Messages
566
Location
Jackson
I remember those. Got my share of shocks off them too while fixing the TVs.

Those were the days. When consumer-grade electronic stuff was repairable. No more.
Yeah, when I owned a repair shop, I really worked at being a boss who could delegate. TVs got delegated. :)

However, I can still feel the hole that the 700+VDC plate circuit in a Marshall guitar amp blew in my finger.
 

C Michael Hoover

Active Member
Joined
Aug 24, 2019
Messages
28
Just different names for the same product.
A search for 'contact grease':
https://www.google.com/search?q=Contact+grease&oq=Contact+grease&aqs=chrome..69i57&sourceid=chrome&ie=UTF-8

Here's a link to the Permatex 22058 'Dielectric Tune-up Grease' TDS (product description and instructions for use), from the Permatex web site:
https://441py33rout1ptjxn2lupv31-wpengine.netdna-ssl.com/wp-content/uploads/tech_docs/tds/22058.pdf

All applications listed for this particular product are low (battery) voltage, except spark plug lead boots (very high voltage). Instructions are to clean the terminals, 'coat both terminals with grease', and re-assemble. Under 'material properties', its chemical type is 'silicone dielectric compound'.

I'm not dissing the use of Vasoline on battery posts; I too have done it countless times. Just saying that my understanding of how dielectric grease is supposed to be used, and how it works, differs significantly from yours.

The stuff I use is made by Harger (of lightning protection fame) and is a copper bearing antioxidant joint compound. Vaseline and the Permatix (as well as others) products are insulators and depend on the "wiping" ability of the contact to ensure a good contact. Thence the insulate the contact from outside corrosive influence. The product that I use enhances the contact as well as keeps outside corrosive influences out.

Further to "rv7cdharlie": Proper installation of a screw and ring terminal termination requires the use of a proper lock washer, rendering any potential loosening of the screw connection an infinitesimally low probably. Tab terminals do loose their tension no matter how much one wishes that they don't. I have trouble shot many, many problems to them over many years.
 
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