Hello all,

I am trying to put a co-ax line through the wall of my shack. I purchased
two chassis mount N-type connectors a while ago, one for inside and one for
outside the shack. As you will know these connectors have a solderable
centre pin for the co-ax inner conductor and seem to rely on the chassis for
the outer connection.

My question is if I use a metal enclosure to mount these N connectors how do
I connect the centre pins together. Do I use co-ax with the braid
disconnected at both ends, or one end, or do I use wire, or just put the
chassis mount N-types to one side and buy some in-line N-types?

I am not too worried about the mechanics of putting the enclosure on the
wall.

Any help would be much appreciated.


73
JOHN

John W jrw wrote:
Hello all,

I am trying to put a co-ax line through the wall of my shack. I purchased
two chassis mount N-type connectors a while ago, one for inside and one for
outside the shack. As you will know these connectors have a solderable
centre pin for the co-ax inner conductor and seem to rely on the chassis for
the outer connection.

My question is if I use a metal enclosure to mount these N connectors how do
I connect the centre pins together. Do I use co-ax with the braid
disconnected at both ends, or one end, or do I use wire, or just put the
chassis mount N-types to one side and buy some in-line N-types?

I am not too worried about the mechanics of putting the enclosure on the
wall.

Any help would be much appreciated.

You don't mention what frequency you are operating on; that makes
quite a bit of difference.

Also what the distance between the two connectors is.

Anything that is small compared to the wavelength of the signal you
are trying to transfer is not so critical.

So on 3.5 MHz you may be able to use a simple wire, while on 3.5 GHz
is is really important to maintain coaxiality.

In article ,
says...
John W jrw wrote:
Hello all,

I am trying to put a co-ax line through the wall of my shack. I purchased
two chassis mount N-type connectors a while ago, one for inside and one for
outside the shack. As you will know these connectors have a solderable
centre pin for the co-ax inner conductor and seem to rely on the chassis for
the outer connection.

My question is if I use a metal enclosure to mount these N connectors how do
I connect the centre pins together. Do I use co-ax with the braid
disconnected at both ends, or one end, or do I use wire, or just put the
chassis mount N-types to one side and buy some in-line N-types?

I am not too worried about the mechanics of putting the enclosure on the
wall.

Any help would be much appreciated.

You don't mention what frequency you are operating on; that makes
quite a bit of difference.

Also what the distance between the two connectors is.

Anything that is small compared to the wavelength of the signal you
are trying to transfer is not so critical.

So on 3.5 MHz you may be able to use a simple wire, while on 3.5 GHz
is is really important to maintain coaxiality.

You incur loss in each connector (.2dB?). I would run the co-ax
through the wall and then put the fitting on inside.

On 12/12/2010 09:35 AM, J. Todd wrote:
In ,
says...
John Wjrw wrote:
Hello all,

I am trying to put a co-ax line through the wall of my shack. I purchased
two chassis mount N-type connectors a while ago, one for inside and one for
outside the shack. As you will know these connectors have a solderable
centre pin for the co-ax inner conductor and seem to rely on the chassis for
the outer connection.

My question is if I use a metal enclosure to mount these N connectors how do
I connect the centre pins together. Do I use co-ax with the braid
disconnected at both ends, or one end, or do I use wire, or just put the
chassis mount N-types to one side and buy some in-line N-types?

I am not too worried about the mechanics of putting the enclosure on the
wall.

Any help would be much appreciated.

You don't mention what frequency you are operating on; that makes
quite a bit of difference.

Also what the distance between the two connectors is.

Anything that is small compared to the wavelength of the signal you
are trying to transfer is not so critical.

So on 3.5 MHz you may be able to use a simple wire, while on 3.5 GHz
is is really important to maintain coaxiality.

You incur loss in each connector (.2dB?). I would run the co-ax
through the wall and then put the fitting on inside.



I'd skip that and run the coax through the wall with no fitting whatsoever

In article ,
"John W" wrote:

Hello all,

I am trying to put a co-ax line through the wall of my shack. I purchased
two chassis mount N-type connectors a while ago, one for inside and one for
outside the shack. As you will know these connectors have a solderable
centre pin for the co-ax inner conductor and seem to rely on the chassis for
the outer connection.

My question is if I use a metal enclosure to mount these N connectors how do
I connect the centre pins together. Do I use co-ax with the braid
disconnected at both ends, or one end, or do I use wire, or just put the
chassis mount N-types to one side and buy some in-line N-types?

I am not too worried about the mechanics of putting the enclosure on the
wall.

Any help would be much appreciated.


73
JOHN

They make a flanged coax connector for RG type cable. You can put two of
those back to back with enough coax to get you thru the wall. OR, You
can just have a 3" Pipe Nipple with screw on Deck Plates made long
enough to pass thru the wall, and then when you have run all your coax
lines thru it, fill the voids with spray foam..... done those, many
times..

--
Bruce in Alaska add path before the @ for email

In article ,
"John W" wrote:

I am trying to put a co-ax line through the wall of my shack. I purchased
two chassis mount N-type connectors a while ago, one for inside and one for
outside the shack. As you will know these connectors have a solderable
centre pin for the co-ax inner conductor and seem to rely on the chassis for
the outer connection.

John-

The chassis mount N connectors should come with a "back shell" that
allows the center pin of Co-ax to be soldered, and the shield to be
soldered to the shell. If transmitting, you need to maintain the shield
to prevent your signal from being leaked from the unshielded wire. The
unshielded wire will act as both a loop antenna and an inductive
reactance in series with the center conductor.

As others suggested, feeding the Co-Ax through the wall may be the best
approach. There is a plastic tube available for doing that. It used to
be sold by Radio Shack as their model 15-1200A "Wall Feed-Through Tube",
but I can't find it at their web site.

Another approach is an MFJ-4602 "Window Antenna feedthru panel". It has
three Co-ax plus balanced, single wire and ground feedthroughs. The
panel is meant to be mounted on a window sill with the window closed
over it.

Fred
K4DII

Thank you for your comments so far folks.

J Todd and Philo, putting the cable straight through the wall omitting the
two connectors is certainly worth me considering.

Rob, to answer your questions I will mainly be using frequencies up to
146MHz but with the hope of going into the low microwave bands in the
future. I will be able to put the connectors back to back so their centre
conductors can be soldered directly to each other. This would mean that the
connector bodies are about 10mm apart.

Thanks again,

JOHN

On 12/12/2010 02:17 PM, John W wrote:
Thank you for your comments so far folks.

J Todd and Philo, putting the cable straight through the wall omitting the
two connectors is certainly worth me considering.

Rob, to answer your questions I will mainly be using frequencies up to
146MHz but with the hope of going into the low microwave bands in the
future. I will be able to put the connectors back to back so their centre
conductors can be soldered directly to each other. This would mean that the
connector bodies are about 10mm apart.

Thanks again,

JOHN





Considering you will be 146 mhz and microwave...
then I'd definably not use any junction at all...
cable straight through the wall

On Dec 13, 6:17*am, "John W"
wrote:
Thank you for your comments so far folks.

J Todd and Philo, putting the cable straight through the wall omitting the
two connectors is certainly worth me considering.

Rob, to answer your questions I will mainly be using frequencies up to
146MHz but with the hope of going into the low microwave bands in the
future. *I will be able to put the connectors back to back so their centre
conductors can be soldered directly to each other. *This would mean that the
connector bodies are about 10mm apart.

Could you cut a small piece of copper pipe of the right diameter in
half then solder it around that centre pin? Simulating a small piece
of hardline coax?