"Geoffrey S. Mendelson" wrote in
:

I recently was able to use a crimp on tool for F connectors for RG-6
quad shield coax. To make sure everyone understands, I am in Israel,
and RG-6 quad shield coax is cheap and easy to find.

Any other coax is almost impossible to find. Pl-259 connectors, called
"UHF" connectors here are rare items. I can get them locally, but I
have to special order them and they are expensive. Since I can not see
them before I order them, I am as likely to get nickle plated ones
with phenolic insulation as I am to get any other kind, and once
ordered are not returnable.

BNC to PL-259 adaptors, are easy to get, and can be ordered from a
reliable local souce for a relatively small price. The same with N to
PL-259.

Looking around at the crimp-on F connectors before I ordered them, I
found that you can get crimp on BNC connectors for RG-6 quad shield
coax.

Here's my questions, Note when I say crimp-on, I mean the ones that
crimp from the rear, like commerical F connectors, not the ones that
crimp around the plug. I have never been able to get any of them to
"fit right":

1. Can I connect a 75ohm BNC plug (which is a different size) to a
50oHm BNC socket?

There is such a thing as a 75 ohm BNC connector, but you are almost
certainly looking at 50 ohm connectors designed for use on 75 ohm cable.
My recollection is that the 75 ohm connectors are incompatible with the
50 ohm connectors, and in some combinations will spread the female inner
part.


2. Are there crimp on 50 ohm BNC plugs which will work with RG6 quad
shield?
I know there are variations, but most are similar in size.
Yes, see http://www.vk1od.net/transmissionline/RG6/index.htm .

3. Are there crimp on N connectors that would fit the RG6 quad shield
coax?

I haven't seen any. I use BNC compression connectors on the RG6, then
BNC/N adapters to connect to the antenna N connector. Works fine, all
waterproof.

More likely due to the size a crimp on center element that screws
into the plug body?

4. Are there crimp on PL-259 connectors?

Yes. They have most of the disadvantages of the PL-259.

If you are of the view that everything that comes out of China, leave
now.

I buy N, BNC, UHF, etc connectors that are of Chinese original that are
economical and excellent quality. But... you have to be picky, price is
not a good indicator of quality.

There is also a prejudice against RG6. Again, quality varies, and you
need to inspect carefully and test product that you might use.

Owen

Thanks in advance,

Geoff.

Owen Duffy wrote:

There is such a thing as a 75 ohm BNC connector, but you are almost
certainly looking at 50 ohm connectors designed for use on 75 ohm cable.
My recollection is that the 75 ohm connectors are incompatible with the
50 ohm connectors, and in some combinations will spread the female inner
part.

Thanks,

The ad I saw said they were 75 ohm. If they really are 50 ohm connectors
for 75 ohm cable, so much the better. Without buying them, I have no way
to tell, and it's awfully expensive to buy one or two.

Shipping from the US to here runs between $20 (USPS) and $50 (FEDEX/DHL/UPS)
for anything. I was going to buy $10 worth of soldering iron tips from
Farnell, and they wanted a flat rate of $35 to ship them. :-(

Yes, see http://www.vk1od.net/transmissionline/RG6/index.htm .

I haven't seen any. I use BNC compression connectors on the RG6, then
BNC/N adapters to connect to the antenna N connector. Works fine, all
waterproof.

Wonderful, thanks.


I buy N, BNC, UHF, etc connectors that are of Chinese original that are
economical and excellent quality. But... you have to be picky, price is
not a good indicator of quality.

URLs??? Please.

There is also a prejudice against RG6. Again, quality varies, and you
need to inspect carefully and test product that you might use.

As in everything in life. :-)

Geoff.


--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM
New word I coined 12/13/09, "Sub-Wikipedia" adj, describing knowledge or
understanding, as in he has a sub-wikipedia understanding of the situation.
i.e possessing less facts or information than can be found in the Wikipedia.

"Geoffrey S. Mendelson" wrote in
:

....
I buy N, BNC, UHF, etc connectors that are of Chinese original that
are economical and excellent quality. But... you have to be picky,
price is not a good indicator of quality.

URLs??? Please.


Jyebao is Taiwanese, not Chinese, and excellent quality. They have an agent
in Israel.

http://www.jyebao.com.tw/agent-u.htm

Owen

Owen Duffy wrote:

Jyebao is Taiwanese, not Chinese, and excellent quality. They have an agent
in Israel.

http://www.jyebao.com.tw/agent-u.htm

Thanks. Interestingly enough, they have F-plugs to N jacks, (i.e. cables
with F plugs on them to connect to a radio with an N jack) but not
F plugs to PL-259(UHF) jacks. :-(

73,

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM
New word I coined 12/13/09, "Sub-Wikipedia" adj, describing knowledge or
understanding, as in he has a sub-wikipedia understanding of the situation.
i.e possessing less facts or information than can be found in the Wikipedia.

In message , Owen Duffy
writes
"Geoffrey S. Mendelson" wrote in
:



1. Can I connect a 75ohm BNC plug (which is a different size) to a
50oHm BNC socket?

There is such a thing as a 75 ohm BNC connector, but you are almost
certainly looking at 50 ohm connectors designed for use on 75 ohm cable.
My recollection is that the 75 ohm connectors are incompatible with the
50 ohm connectors, and in some combinations will spread the female inner
part.

For all intents and purposes, 50 and 75 ohm BNCs (both male and female)
are interchangeable. They have essentially the same dimensions. You
might just see that the 50 ohm male has a rather stubby point, whereas
the 75 ohm version has a somewhat more steadily-tapered pin - but,
unlike N-connectors, the 50 ohm male certainly doesn't cause damage to a
75 ohm female.

The thing which mainly causes the impedances to differ is the amount of
PTFE dielectric present, in both sexes. On the 75 ohm version, you will
normally see that it has been reduced considerably compared with the 50
ohm. Even with less dielectric, the 75 ohm version is still a bit
unhappy with having too much, and this tends to lower the impedance to
somewhat less than 75 ohms.

However, for all intents and purposes, you probably won't notice any
significant difference between 50 and 75 ohm BNCs (mixed or not).
--
Ian

[Sorry for being a little late to the party, but I was off newsgroups most
of this week.]

This thread had some discussion of adapters and I want to share my bad
experience with some low-cost items, proving, once again, that you get what
you pay for.

I am testing all my adapters and discarding some because the assemblies are
pulling apart with very little force. One manifestation: tightening the
threaded ring on a PL-259 (either cable end connector or adapter) and having
the ring just continue all the way on, separating from the connector body.

One test for a future failure has been any lack of smoothness when I rotate
the ring while tugging it gently. If it binds, rather than turning smoothly
in my hands, it's going to fail. Also, some of the cheap connectors are
press-fit together very poorly; they pull apart with only a few pounds of
pull.

Most of my early exposure to coax connectors was in and around the US Navy,
where reliable connectors are the rule, so I was a spoiled child.

"Sal"
(KD6VKW)

On 06/13/2010 01:50 PM, Sal M. O'Nella wrote:

[Sorry for being a little late to the party, but I was off newsgroups
most of this week.]

This thread had some discussion of adapters and I want to share my bad
experience with some low-cost items, proving, once again, that you get
what you pay for.

I am testing all my adapters and discarding some because the assemblies
are pulling apart with very little force. One manifestation: tightening
the threaded ring on a PL-259 (either cable end connector or adapter)
and having the ring just continue all the way on, separating from the
connector body.

One test for a future failure has been any lack of smoothness when I
rotate the ring while tugging it gently. If it binds, rather than
turning smoothly in my hands, it's going to fail. Also, some of the
cheap connectors are press-fit together very poorly; they pull apart
with only a few pounds of pull.

Most of my early exposure to coax connectors was in and around the US
Navy, where reliable connectors are the rule, so I was a spoiled child.

"Sal"
(KD6VKW)

PL-259's I can handle.
BNC's drive me nuts trying to get a good connection.
I gave up and just buy my cables now.
Bill

In article ,
says...

On 06/13/2010 01:50 PM, Sal M. O'Nella wrote:

[Sorry for being a little late to the party, but I was off newsgroups
most of this week.]

This thread had some discussion of adapters and I want to share my bad
experience with some low-cost items, proving, once again, that you get
what you pay for.

I am testing all my adapters and discarding some because the assemblies
are pulling apart with very little force. One manifestation: tightening
the threaded ring on a PL-259 (either cable end connector or adapter)
and having the ring just continue all the way on, separating from the
connector body.

One test for a future failure has been any lack of smoothness when I
rotate the ring while tugging it gently. If it binds, rather than
turning smoothly in my hands, it's going to fail. Also, some of the
cheap connectors are press-fit together very poorly; they pull apart
with only a few pounds of pull.

Most of my early exposure to coax connectors was in and around the US
Navy, where reliable connectors are the rule, so I was a spoiled child.

"Sal"
(KD6VKW)

PL-259's I can handle.
BNC's drive me nuts trying to get a good connection.
I gave up and just buy my cables now.
Bill

Sal's right - it's down to the quality of the item. I've seen some poor
BNCs, but many PL-259s which were REAL rubbish. I expect it's because
many of them are used for CB - and price is the usual decider there.

I've standardised on 50R BNCs for everything. Usually Amphenol or
Greenpar - the extra cost is insignificant, compared to rig prices these
days. Why 50R - the only reason is that the sockets are more robust.

Ready made BNC cables have been a disappointment - they are usually
crimped, and the crimps seem to relax with age. Cables can pull out,
given a bit of a tug. I use solder/clamped connectors and always solder
the braid to the clamping sleeve. Never had a failure.....

"Gaius" wrote in message
...
In article ,
Cables can pull out,
given a bit of a tug. I use solder/clamped connectors and always solder
the braid to the clamping sleeve. Never had a failure.....


After I got out of the Navy, I worked as a Marine Electrician, installing
equipment on Navy ships. My foreman told me that it is rarely done, but the
Navy can perform a Quality Assurance "pull test" of 25 lbs on a connector.
I think that's a lot of pull for a connector to withstand.

Sal M. O'Nella wrote:

After I got out of the Navy, I worked as a Marine Electrician,
installing equipment on Navy ships. My foreman told me that it is
rarely done, but the Navy can perform a Quality Assurance "pull test" of
25 lbs on a connector. I think that's a lot of pull for a connector to
withstand.

In a previous life I was tasked with tailoring a large number of RG-58
cables connecting radar scopes at a new installation in Korea. This
involved cutting the cables to length and installing clamp and solder
type BNC connectors. The rumor was that the Korean troops were supposed
to be helping us, but we never saw them -- until one day, when they
showed up. The one assigned to help me sat down and, neither of us being
fluent in the other's language, I proceeded to show him how to assemble
the connector.

Now the job of one of the several pieces, a metal ring, is to push
against and expand a rubber washer, which is mainly what holds the
connector together. This piece looks like it should go upside down from
the correct orientation, but if put on that way, the rubber washer won't
expand and the connector will come off very easily, with only a gentle
tug. If assembled correctly, it'll take a lot of pulling, as Sal says,
to get it off. I've never seen a correctly assembled connector come off.

Getting back to the story, I carefully demonstrated the correct assembly
method to the Korean troop, emphasizing the orientation of the ring.
After putting the connector on, I showed him our standard test. We would
grab the connector in one hand and about two feet down the cable with
the other. Then we put our hands together, making a loop of cable, and
briskly yanked them apart, resulting in a really good sharp tug on the
connector. A properly assembled connector had no trouble with this test.

So I gave him the parts and went to work on a connector. After a while
he handed me the cable with attached connector. I gave it the tug test
and the connector snapped right off. So I repeated the mimed
instructions, with extra emphasis on the ring orientation, then put him
to work again and got back to what I was doing. When he was finished he
handed me the connector, I did the yank test, and again the connector
popped right off. He shrugged, muttered something under his breath, got
up, and left. Guess he figured he'd had enough of that game, where he
assembled connectors and I pulled them off. We never saw the Korean
troops again.

Roy Lewallen, W7EL