BNC installation

I'm about ready to splice on a good fin & boom to a badly broken
Puchacz fuselage. Made a clean cut 56" aft of the aft lift fittings,
glued in a sleeve, jigged up the two pieces (both sides straight, top
& bottom straight, fin vertical, lift fittings horizontal), spliced
the push-rod, hooked up the TE tube, now all I have to do is splice
the radio cable, right? Always hated trying to solder that little
center post on the BNC, especially working inside a fuselage half with
short leads. Found a BNC crimper from Aircraft Spruce & Specialty for
about $200 bucks with proper die and a hand full of BNC's. Works slick
as snot, just slide on the sleeve, trim the cable as before, slip on
the center post and crimp it, then slide on the BNC body, shove the
sleeve down over the exposed shield and crimp it also. That's it, all
done!
I installed one male and one female connector (legal in all states).
Some may wish to use two females with a male to male coupler (only
legal in some states).
JJ

You really want that thing rattling about inside the fuselage? With
all the work you have already done on the fuselage, is it THAT much
harder to replace the entire cable?

Anyway, you could have found a much less expensive crimper at an
electronics store (Fry's, Radio Shack, Newark, etc.). I suspect that
the only ones who solders anymore is the military, and me sometimes--
and yes, I hate it too--even though I have a considerably less
expenseive crimper.



On Jun 24, 7:28*am, JJ Sinclair wrote:
I'm about ready to splice on a good fin & boom to a badly broken
Puchacz fuselage. Made a clean cut 56" aft of the aft lift fittings,
glued in a sleeve, jigged up the two pieces (both sides straight, top
& bottom straight, fin vertical, lift fittings horizontal), spliced
the push-rod, hooked up the TE tube, now all I have to do is splice
the radio cable, right? *Always hated trying to solder that little
center post on the BNC, especially working inside a fuselage half with
short leads. Found a BNC crimper from Aircraft Spruce & Specialty for
about $200 bucks with proper die and a hand full of BNC's. Works slick
as snot, just slide on the sleeve, trim the cable as before, slip on
the center post and crimp it, then slide on the BNC body, shove the
sleeve down over the exposed shield and crimp it also. That's it, all
done!
I installed one male and one female connector (legal in all states).
Some may wish to use two females with a male to male coupler (only
legal in some states).
JJ

raulb wrote:
You really want that thing rattling about inside the fuselage? With
all the work you have already done on the fuselage, is it THAT much
harder to replace the entire cable?

Most antenna cables are epoxied to the fuselage at several locations
and can't be simply "replaced", also a new cable must be secured at
several locations in order to keep it from flopping around or it could
get tangled up with the elevator push-rod, couldn't it? Also, even it
I replaced the whole cable I would still have to connect it to the
antenna with a BNC, wouldn't I? Ever try to install a BNC inside a
fin? I have and decided connecting the two cables at the point of the
repair is the best way to go.

Just before closing the two halves of the fuselage, I will goop up the
BNC's & TE tube and secure them to one side with a string that goes
outside so that I can pull them tight and they can't "rattle around"
inside the fuselage.
This is not my first rodeo,
JJ

"raulb" wrote in message
...
Anyway, you could have found a much less expensive crimper at an
electronics store (Fry's, Radio Shack, Newark, etc.). I suspect that
the only ones who solders anymore is the military, and me sometimes--
and yes, I hate it too--even though I have a considerably less
expenseive crimper.

This is one time when you want the professional tool. (Of course, you want
to buy the professional tool at the best price, and that is probably not any
aviation supplier)

I would rather have a crimped BNC than a soldered BNC any day of the week.
There are just too many ways to do the job wrong. A crimp connector is closer
to idiot proof. Additionally, it gives you a more reliable braid connection
than the older style solder-type connectors.


Vaughn

What am I missing here? What do "some states" have to do with an
aircraft antenna installation?

At 14:28 24 June 2008, JJ Sinclair wrote:
I'm about ready to splice on a good fin & boom to a badly broken
Puchacz fuselage. Made a clean cut 56" aft of the aft lift fittings,
glued in a sleeve, jigged up the two pieces (both sides straight, top
& bottom straight, fin vertical, lift fittings horizontal), spliced
the push-rod, hooked up the TE tube, now all I have to do is splice
the radio cable, right? Always hated trying to solder that little
center post on the BNC, especially working inside a fuselage half with
short leads. Found a BNC crimper from Aircraft Spruce & Specialty for
about $200 bucks with proper die and a hand full of BNC's. Works slick
as snot, just slide on the sleeve, trim the cable as before, slip on
the center post and crimp it, then slide on the BNC body, shove the
sleeve down over the exposed shield and crimp it also. That's it, all
done!
I installed one male and one female connector (legal in all states).
Some may wish to use two females with a male to male coupler (only
legal in some states).
JJ

You obviously don't live in California.

Nyal Williams wrote:
What am I missing here? What do "some states" have to do with an
aircraft antenna installation?

At 14:28 24 June 2008, JJ Sinclair wrote:
I'm about ready to splice on a good fin & boom to a badly broken
Puchacz fuselage. Made a clean cut 56" aft of the aft lift fittings,
glued in a sleeve, jigged up the two pieces (both sides straight, top
& bottom straight, fin vertical, lift fittings horizontal), spliced
the push-rod, hooked up the TE tube, now all I have to do is splice
the radio cable, right? Always hated trying to solder that little
center post on the BNC, especially working inside a fuselage half with
short leads. Found a BNC crimper from Aircraft Spruce & Specialty for
about $200 bucks with proper die and a hand full of BNC's. Works slick
as snot, just slide on the sleeve, trim the cable as before, slip on
the center post and crimp it, then slide on the BNC body, shove the
sleeve down over the exposed shield and crimp it also. That's it, all
done!
I installed one male and one female connector (legal in all states).
Some may wish to use two females with a male to male coupler (only
legal in some states).
JJ

On Jun 24, 1:58*pm, Nyal Williams wrote:
What am I missing here? *What do "some states" have to do with an
aircraft antenna installation?

Or you could install one male with two (or more) females. Not legal in
any state, but tolerated in Nevada, Texas, Arizona and Utah!.

Think about it, Nyle. It will come to you.
:) JJ

I wish I had known about the BNC crimpers decades ago. At this point, I
would drive 100 miles to get a proper crimper instead of soldering a BNC -
they are that much better. When someone asks me to assist on their radio
installation, the first thing I look at is the BNC connector. Usually, I
can stop there.

You do not want to buy a cheap one - but electronics supply houses sell them
for under $50. Make sure it is for 50 ohm coax and not 70 ohm stuff. Many
of the good crimpers have dies that fit into the jaws for each different
type of coax.

For the price of a good steak dinner, you can make life simpler and better.

Colin Lamb

I forgot one other point - get quality, name brand coax fittings. A few
years ago, some Chinese right angle coax fitting showed up. They looked
good, but used a spring of wire to connect the two terminations. Not good!
They were much easier to make.

Colin

Some comments;

1) Crimping is very much the way to go. The heat of soldering (unless
you are very careful) can easily damage the dielectric insulator.
Invariably you are then left with a blob of solder that must be
wittled away to make thing fit. Ugh.
2) The less expensive sub-$50 (but not dirt cheap) crimpers seem to
work fine. Ratcheting type is highly recommended as they enforce the
correct amount of pressure. The $200 units are made to hold up to
repeated use over years, something most of us are unlikely to need.
3) Male/Female versus Two Males with coupler (whoa!) - Stick with the
fewest possible connections. Not only for the fact that there are
fewer things to go wrong but because each extra connection looses 2db
(rule of thumb) of your power.
4) While the boom is open, think about (if possible/practical/useful)
pulling extra air lines, coax, etc.
5) Test, test, test, test and test again before buttoning this up.
Get a professional to help out. Well worth the expense. Much better
now than later.
6) If you are on the scene of a boom break (I have), resisting with
all your might the temptation of cutting all the lines (air, coax) to
speed up the removal of the dead beast from the scene of the crime.
It is much better to try to take the time to disconnect things at the
cockpit end and pull them back so that any necessary splicing is done
in a easily accessible place.

Enjoy, John DeRosa