I have several similar plumbers delight RF connectors...
We used to have a metal turning lathe which was very handy for taking a
compression coupling and cutting it in half, you only need one side of
the coupling...
I have also found that the compression fittings have a "ring" that
slides over the copper tube, when the nit os tightened this makes the
"seal"... this ferrule is, on some CATV line, just a little too small a
diameter to let the hardline pass through it. I simply cut it with some
HD dikes and once it is inside the nut and under compression it seems to
hold just fine...
I am a big fan of phenolic (old fashioned) PL259's - recommend them when
you are doing surgery like center pin removal, too... the ones with
Teflon (mebbe not, simply white plastic) would rather fall apart than
machine out...
It is a bit time consuming to fabricate these but they do work...
FWIW on a related (free coax thread) I am reminded of the technique used
by W3AU for splicing his TV hardline runs - he had the stuff everywhere
at his FL QTH...
Ed would obtain some tubing which had an ID the same as the OD of the
hardline...
He would expose the center conductor on either side of the splice....
Then he would slide a short length of the tubing over one side of the
splice...
The center conductors would be soldered together - if you wanna get
fancy you can get some brass tubing at a hobby shop to act as a "double
female" for the center conductor...
Ed would then take some insulation from opening up the hard line and
"re-pack" it in the area of the splice to keep the center conductor in
the center... then, he would slide that piece of tubing over the whole
mess and hose clamp it shut...
Apply weatherproofing - voila - inexpensive splice!
Simple is good! Imagine you do see an impedance bump there - but at HF
frequencies it is negligible!
73,
K4OJ
Gerry Smith wrote:
> Several have asked me to elaborate after my post regarding using
> plumbing fittings to connect to hardline. Here goes:
>
>
>
> I have hardline with a solid aluminum shield. The shield is ? inch in
> diameter.
>
>
>
> I purchase a plumbing fitting that has a compression coupling on one end
> that is made for ? inch copper tubing. In other words, the ID of the
> compression end is ? inch. I use Penetrox and compress the connection to
> the hardline shield. The other end has inside threads for ? inch OD
> pipe. I drill out the threads with a ? inch drill. The body of a PL-259
> is ? inch. I then solder the PL-259 in place (after removing the center
> pin, see below).
>
>
>
> I drill out the center conductor pin of a PL-259 with a bit the size of
> the diameter of the center conductor of my hardline, which is .172 inch.
> The center conductor fits directly, and nicely, into a SO-239. So, I
> have a bit of an air dielectric in the brass fittings but works just
> fine.
>
>
>
> You may have different size hardline, and thusly different dimensions. I
> suggest you take a piece of your hardline, a PL-259, and a SO-239 down
> to your local professional plumbing supplier and ask them to help.
>
>
>
> Gerry Smith, W6TER
>
>
>
>
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
> questions and ask for Sherman, W2FLA.
>
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