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Ian Jackson[_2_] Ian Jackson[_2_] is offline
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Default Increasing Cable TV signal strength

In message
,
JIMMIE writes
On Feb 10, 11:38*am, Jeff Liebermann wrote:
On Fri, 10 Feb 2012 06:17:03 -0800 (PST), JIMMIE

wrote:
Jeff, I installed TVRO systems for several years and used a lot of F
connectors. Suprisingly the ones I found that worked best were the
ultra cheap ones that only took a pair of pliers to fasten *These were
the ones with the separate crimp rings. Used with some good quality
heat shrink tubing this eliminated most of the problems you mention. I
dont know why these connectors went away, my only guess is *that
someone wasn't making enough money on them.


Jimmie


Yech...

Please try this test. *Insert such a crimp type F connector and cable
into some useless piece of equipment with a type F jack. *Pull on the
cable hard. *In my experience, it doesn't take much to make the cable
and connector part ways. *Repeat with a screw on connector. *Now,
repeat the experiment using a properly assembled compression type F
connector and cable. *It takes considerably more brute force to break
the connection. *I think the official minimum pull test is 55 lbs, but
I'm too lazy to Google for it now.

Hiding the workmanship under shrink tube is not very functional. *It
will have little effect on the pull test.

Most of the cable leakage problems I've seen (and found) were due to
crimp type F connectors coming apart or badly crimped. *That includes
both the hex shaped crimp, and ones held together with a crimped ring.

Bad:
http://www.fconnector.org/wp-content/uploads/2011/12/F-Connector2.jpg

Worse:
http://www.showmecables.com/images/catalog/product/F-connector-RG59.j...

Good:
http://images.lowes.com/product/converted/783250/783250926510lg.jpg

--
Jeff Liebermann * *
150 Felker St #D * *http://www.LearnByDestroying.com
Santa Cruz CA 95060http://802.11junk.com
Skype: JeffLiebermann * * AE6KS * *831-336-255


Sorry Jeff but I never used my connectors to support my cables. You
may be right but completely irrelevant to me. To me F connector and
good connection shouldn't even be used in the same sentence. They are
what that are, cheap connectors at best that uses the center conductor
of the cable for a contact. Now that is Yech. Heat shrink has nothing
to do with the pull test or hiding poor workmanship but it does help
keep corrosion down which is the biggest problem with F connectors.
Ive never seen one pull apart except in the shoddiest of
installations. One of the best things I have found to insure you
maintain a good connection is to apply something like DeOxit to the
connectors when you assemble them. Best done while all the parts are
new.

There little wrong with good quality F-connectors. They are generally
good enough for what they were intended for. Problems are usually down
to who installs them, and how.

For personal outdoor use, I always give any connectors a squirt of WD40
- both during and after installation. [I guess DeOxit would be similar
or better.] After cleaning off most of the WD40, I then seal with
self-amalgamating tape. Obviously, heatshrink would be better, but for
me, is usually less convenient.

Mechanically, even screw-on Fs can be hard to dislodge, provided just
the right amount of braid is trapped under the screw thread. However, I
suppose that sometimes they might not provide the ultimate in screening.

In the UK, in the large CATV networks, crimped connectors are well and
truly a thing of the past. Anyone using them (even the good ones) would
be liable to be hung, drawn and quartered, and then severely punished.

The standard connector is of the 'Snap and Seal' type (and similar). In
themselves, these are pretty well watertight, and the screening is
excellent. It should be almost impossible to pull one off the cable.

However, it is unusual for F-connections to appear naked in the open
air. The final RF distribution to the home is invariably from a street
cabinet which houses an optical node or an RF distribution / line
extender amplifier feeding a bank of taps/splitters. The 'traditional'
cascade of in-line taps has not been used for a very long time. Under
these relatively benign conditions, the F-connectors probably suffer
much less from corrosion than those used on taps hanging on aerial
messenger wires, USA-style. Nevertheless, there are various purpose-made
short 'chunky' rubber sleeves which can be installed first on the tap
ports before the cable connectors are screwed on. These seal the screw
threads. Personally, I would have liked to have seen a bit of WD40 used
but I never managed to drum up much enthusiasm for this as an approved
practice.
--
Ian