Make your own hardline?
 

Hardline is good stuff, right? Does anyone make their own out of
copper water pipe?

Seems doable, but have never heard of anyone doing it.

This is what happens when I have too much time on my hands. :-)


--
Bill, W6WRT

Make your own hardline?
 

Here in southern Oklahoma enterprising copper thieves are stealing ground
wires off power poles and copper tubing from outside air conditioner units,
I think their beady little eyes would glow happily at the sight of a hundred
and fifty or two hundred feet of DIY copper hardline in someones back yard.
Shoot, they'd probably jump the fence flatfooted and fight your family dog
for 25 feet of it.

Harold
KD5SAK

"Bill Turner" wrote in message
...
Hardline is good stuff, right? Does anyone make their own out of
copper water pipe?

Seems doable, but have never heard of anyone doing it.

This is what happens when I have too much time on my hands. :-)


--
Bill, W6WRT

Make your own hardline?
 

ORIGINAL MESSAGE:

On Tue, 12 Sep 2006 15:17:26 GMT, "kd5sak"
wrote:

Here in southern Oklahoma enterprising copper thieves are stealing ground
wires off power poles and copper tubing from outside air conditioner units,
I think their beady little eyes would glow happily at the sight of a hundred
and fifty or two hundred feet of DIY copper hardline in someones back yard.
Shoot, they'd probably jump the fence flatfooted and fight your family dog
for 25 feet of it.

Harold
KD5SAK

------------ REPLY FOLLOWS ------------

Paint it white so it looks like PVC?


--
Bill, W6WRT

Make your own hardline?
 

"Bill Turner" wrote in message
...
Hardline is good stuff, right? Does anyone make their own out of
copper water pipe?

Seems doable, but have never heard of anyone doing it.

This is what happens when I have too much time on my hands. :-)


--
Bill, W6WRT

Yes you can roll your own hard line, Im not sure its worth it though. I had
about 100ft of Cu pipe that had been setting around for about 30 years. I
would have probably been better off selling the pipe and buying the
hardline. After I realisesd I would have to keep it pressurised ti keep out
the water I pulled it out and replaced it with LMR 900.

Make your own hardline?
 

There is an apocryphal story that 50 ohms started out as a common impedance
for coax because that happened to be the number that came out using common
British copper pipe sizes.

73
Jeff

Make your own hardline?
 

It's possible... there are quite a few standard copper pipe sizes that
come out to 50 ohms.

I think supporting dielectric disks or whatever are the hard part in
rolling your own. We did actually build a small section of 50 ohm
hardline for a sodium droplet pinch-off experiment here... I think it
was 1/2" pipe inside 1 1/2" pipe.

If you were trying to do a long run of it, though, you'd quickly get
into assembly hell. #10 wire inside 1/4" refrigeration tubing comes
out awfully close to 37 ohms; tried to make a matching section for a
440 MHz yagi this way, but I couldn't figure out how to keep it
centered, so it never worked out.

Dan

Jeff wrote:
There is an apocryphal story that 50 ohms started out as a common impedance
for coax because that happened to be the number that came out using common
British copper pipe sizes.

73
Jeff

Make your own hardline?
 

Jeff wrote:
There is an apocryphal story that 50 ohms started out as a common impedance
for coax because that happened to be the number that came out using common
British copper pipe sizes.

I vaguely remember something about 50 ohms being good
for transmitting and 73 ohms being good for receiving.
--
73, Cecil http://www.w5dxp.com

Make your own hardline?
 

At about $25 for ten feet of 3/4" copper pipe, plus lots of time to put
it together, why bother? I have made short sections for matching and
the like, but wouldn't consider trying to make a long run of it. I do
still have some scraps of 1" thick Teflon from when I helped make a
quarter-wave length of 22 ohm 6-1/8" flanged line to go from 50 ohms to
10 ohms (five 50-ohm ports in parallel). Wow, that was a long time ago
now.

Cheers,
Tom

Bill Turner wrote:
Hardline is good stuff, right? Does anyone make their own out of
copper water pipe?

Seems doable, but have never heard of anyone doing it.

This is what happens when I have too much time on my hands. :-)


--
Bill, W6WRT

Make your own hardline?
 

Cecil Moore wrote:
I vaguely remember something about 50 ohms being good
for transmitting and 73 ohms being good for receiving.
____________

50 ohm line is about optimum for power handling, given the ID of the
outer conductor, and 75 ohm line has about the least attenuation for a
given ID of the outer conductor. I think a European compromise was to
choose 60 ohms as a standard impedance.

RF

Make your own hardline?
 

Jeff wrote:
There is an apocryphal story that 50 ohms started out as a common impedance
for coax because that happened to be the number that came out using common
British copper pipe sizes.

The research I've done indicates that the old British pipe sizes
(1/2",. 3/4", 1") specified internal dimensions, while the new pipe
sizes use external dimensions and a wall thickness. Did the story take
into account this change in convention?

Zack Lau W1VT