[Dan Richardson[_2_]]

On Wed, 30 Apr 2008 23:53:38 GMT, "HRBE" wrote:

Hello to all,
I have just bought a Ground plane adaptor off Ebay (yeah I know!) (China!
Yeah I know!) it was advertised as a PL259/SO239 male/female thread to
enable a groundplane to be fitted to a mobile antenna.

I assumed wrongly that there was an International standard with regard to
the PL259/SO239.

Naturally when a known part number is advertised, one would expect that the
normal 5/8" x 24 threads per inch standard (UNEF) would be followed.

Not so! What was sent was a 16 x 1mm adaptor.

Naturally the language difference is making it hard for me to convince the
seller that he MUST advertise the adaptor on Ebay having a metric thread.

Can anyone tell me if there is a move towards the metrification of the
PL259/SO239 connectors?

If this happens all hell will break loose, imagine trying to connect antenna
to coax at say a field day or even worse in an emergency situation?

John
VK2KCE


I ran into that problem many years ago when they first starting
importing some off-shore VHF antennas. I ended up purchasing a 5/8-24
NF die-nut and that took care of the problem. Its very easy to use
requiring very little pressure to "chase" the threads so that a
standard PL-259 screws on without any problem.

Over the years having that die-nut has paid for itself many times for
myself and friends who ended up trying to use metric connectors with
American standard connectors.

Danny, K6MHE

[John VK2KCE]

Thanks Dan,
I have ordered a die nut to correct the problem, I suspect that the thread
will not have the full strength after using it though!

Thanks, John
"Dan Richardson" wrote in message
...
On Wed, 30 Apr 2008 23:53:38 GMT, "HRBE" wrote:

Hello to all,
I have just bought a Ground plane adaptor off Ebay (yeah I know!) (China!
Yeah I know!) it was advertised as a PL259/SO239 male/female thread to
enable a groundplane to be fitted to a mobile antenna.

I assumed wrongly that there was an International standard with regard to
the PL259/SO239.

Naturally when a known part number is advertised, one would expect that
the
normal 5/8" x 24 threads per inch standard (UNEF) would be followed.

Not so! What was sent was a 16 x 1mm adaptor.

Naturally the language difference is making it hard for me to convince the
seller that he MUST advertise the adaptor on Ebay having a metric thread.

Can anyone tell me if there is a move towards the metrification of the
PL259/SO239 connectors?

If this happens all hell will break loose, imagine trying to connect
antenna
to coax at say a field day or even worse in an emergency situation?

John
VK2KCE


I ran into that problem many years ago when they first starting
importing some off-shore VHF antennas. I ended up purchasing a 5/8-24
NF die-nut and that took care of the problem. Its very easy to use
requiring very little pressure to "chase" the threads so that a
standard PL-259 screws on without any problem.

Over the years having that die-nut has paid for itself many times for
myself and friends who ended up trying to use metric connectors with
American standard connectors.

Danny, K6MHE

[Jeff]

"John VK2KCE" wrote in message
...
Thanks Dan,
I have ordered a die nut to correct the problem, I suspect that the thread
will not have the full strength after using it though!


Whist running a die over the thread will allow a 'normal' 259 the be screwed
onto the socket it does reduce some of the thread to almost nothing, so I
would not recommend that method where there is any mechanical strength
required such as an antenna base.

73
Jeff

[Dan Richardson[_2_]]

On Mon, 12 May 2008 12:44:23 +0100, "Jeff" wrote:


"John VK2KCE" wrote in message
...
Thanks Dan,
I have ordered a die nut to correct the problem, I suspect that the thread
will not have the full strength after using it though!


Whist running a die over the thread will allow a 'normal' 259 the be screwed
onto the socket it does reduce some of the thread to almost nothing, so I
would not recommend that method where there is any mechanical strength
required such as an antenna base.

73
Jeff

In over 20+ years of use I have never experienced anything like that.
If you think about it, the difference between the metric and american
threads - in the case is - is slight (Look just how far you can screw
a PL-59 on the meteric socket) and a very small amout of material is
removed.

Have you really ever tried this method?

73,
Danny, K6MHE

[Dan Richardson[_2_]]

On Mon, 12 May 2008 08:11:56 GMT, "John VK2KCE"
wrote:

Thanks Dan,
I have ordered a die nut to correct the problem, I suspect that the thread
will not have the full strength after using it though!

Once you try this method you see that you really have nothing to be
concerned about. (Unless you use a wrench and really apply heavy
pressure on a PL-259.) For hand tightening you'll have no problems.

73, Danny.

[Jeff]

Whist running a die over the thread will allow a 'normal' 259 the be
screwed
onto the socket it does reduce some of the thread to almost nothing, so I
would not recommend that method where there is any mechanical strength
required such as an antenna base.

73
Jeff

In over 20+ years of use I have never experienced anything like that.
If you think about it, the difference between the metric and american
threads - in the case is - is slight (Look just how far you can screw
a PL-59 on the meteric socket) and a very small amout of material is
removed.

What you will see if you actually try this method is that the threads will
be reduced in thickness over about half the length. The reduction getting
worse as you progress. The threads will have reduced to such an extent
towards the end as to render then no more than bumps. Have a look at one you
have done this to under a magnifying glass and you will see.

73
Jeff

[Danny Richardson[_2_]]

On Mon, 12 May 2008 15:21:49 +0100, "Jeff" wrote:


Whist running a die over the thread will allow a 'normal' 259 the be
screwed
onto the socket it does reduce some of the thread to almost nothing, so I
would not recommend that method where there is any mechanical strength
required such as an antenna base.

73
Jeff

In over 20+ years of use I have never experienced anything like that.
If you think about it, the difference between the metric and american
threads - in the case is - is slight (Look just how far you can screw
a PL-59 on the meteric socket) and a very small amout of material is
removed.

What you will see if you actually try this method is that the threads will
be reduced in thickness over about half the length. The reduction getting
worse as you progress. The threads will have reduced to such an extent
towards the end as to render then no more than bumps. Have a look at one you
have done this to under a magnifying glass and you will see.

73
Jeff


Jeff,

The TPI between the two standards (American and metric) - in this
case - are very close resulting in very little thread stock being
removed. In the short thread length involved here (about 1/2-inch) and
the threads are not rendered to nothing more than bumps.However, at
longer thread lengths it well could be a problem, but not at the
1/2-inch distance we are talking about here.

Again I ask, have you actually tried this?

I have used this method numerous times for myself and friends and I
have never experienced any kind of failures or problems in doing so.

That said I'm going QRT on this subject.

73,
Danny, K6MHE

[Jeff]

The TPI between the two standards (American and metric) - in this
case - are very close resulting in very little thread stock being
removed. In the short thread length involved here (about 1/2-inch) and
the threads are not rendered to nothing more than bumps.However, at
longer thread lengths it well could be a problem, but not at the
1/2-inch distance we are talking about here.

Again I ask, have you actually tried this?

I have used this method numerous times for myself and friends and I
have never experienced any kind of failures or problems in doing so.


Yes. and I would not trust the end result to any kind of load, it is fine
for a cable connection but certainly not as a method of retaining a mobile
antenna at speed!

Perhaps the difference is in the die, and the length of thread in the die.
The thicker the die the truer the thread will be and the more pronounced the
removal of the metric thread.

The OP was suggesting a 'die nut' which will be quite thick and I suspect
would produce results similar to those I have found.

Jeff

[Jeff]

The TPI between the two standards (American and metric) - in this
case - are very close resulting in very little thread stock being
removed.

In fact the TPI's are not that close 24tpi for American (1.06mm pitch) and
1.5mm pitch for Metric fine.

Jeff

[Gene Fuller]

Jeff wrote:
The TPI between the two standards (American and metric) - in this
case - are very close resulting in very little thread stock being
removed.

In fact the TPI's are not that close 24tpi for American (1.06mm pitch) and
1.5mm pitch for Metric fine.

Jeff



The metric PL259 has a pitch of 1.0 mm. It is not an ordinary metric
fine thread. (5/8 - 24 is not an ordinary fine thread either.)

73,
Gene
W4SZ