[AMRadio] Dow Corning DC 4

[oldradio at comcast.net]

In the Bell system we used a product called NO-OX-ID and NO-OX-ID "A-SPECIAL" 

We spread it on all DC electrical connections, buss bars and power cable ends.

NO-OX-ID ... THE ORIGINAL RUST PREVENTIVE. This anti corrosion coating requires minimal surface preparation and is the long-term solution for lubrication and corrosion control. NO-OX-ID A-Special is used as an anti condensation coating on structural steel, in acid pickling areas, brine tanks, inside water tanks, steel cables, bridges and cofferdams. Use this cosmoline type corrosion resistant coating whenever the use of heavy duty rust preventives and anti condensation coatings are required.

NO-OX-ID "A-SPECIAL" is the electrical contact grease of choice in new electrical installations and maintenance because of its excellent performance in keeping metals free from corrosion. This rust preventitive has been used for over 50 years to preventing corrosion in electrical connectors from low micro-power electronics to high voltage switchgear. NO-OX-ID A-Special prevents the formation of oxides, sulfides and other corrosion deposits on copper and aluminum surfaces and conductors can be prevented with its use.

http://www.sanchem.com/

It's available from a 1-oz size up to quart size and I guess larger sizes.  Search the Internet for vendors.

73, John Dilks, K2TQN


-.-

>
> On Mon, Sep 19, 2011 at 2:32 PM, Jim Wilhite <w5jo at brightok.net> wrote:
>
>> A couple of weeks back I asked if anyone knew what the grease
>> composition was in the little packets furnished with commercial VHF
>> antennas.  Several people responded with the answer Dow Corning DC 4.
>>
>> I had a friend who send me a couple of packets and I put it in several
>> connectors that I am using now in my temporary transmission line.  First
>> I measured the reflected power into a dummy load from 1.8 up to 29 Mc.
>> I did that in the middle of the 6 bands.
>>
>> Then I put the grease in one connector and measured at the same points.
>> The reflected power did not change so I put it in the rest of the
>> connectors.  Still the reflected power did not change and the power
>> measured at the dummy load did not change.
>>
>> Given those results I clinched my jaw and ordered a tube of it, about 5
>> oz.  I forget the exact cost but it was about $20.  I made the decision
>> to put the grease in my PL 259 connectors because over the years I have
>> used them in all sorts of installations.  I put tape around them, I put
>> heat shrink over them after taping them but in most cases I found
>> corrosion on the center pin from condensation.
>>
>> So by filling the connector this should help keep that problem down to a
>> very little bit.  I hope this time I never have to move and this will
>> last from now on.  Thanks to all of you who posted your thoughts and
>> suggestions.  In my measurements it is a worth while thing to do
>> particularly if you live in high humidity areas.
>>
>> The only thing to watch is it has silicone in it.  If you use it on
>> something to be painted, you will regret it.  Paint will not stick to
>> surfaces that have had silicone on them.  And it does not matter how
>> much you clean the surface, it will always cause trouble.
>>
>> Jim/W5JO
>>
>> _____________