Re: [time-nuts] GPS-Attached Equipment Lightning Protection

[SAIDJACK]

Hello Alan,
 
>rod. The likelihood of getting any significant voltage on the  center
>conductor I would think would be very small.
 
A lightning strike is not your normal static discharge. The magnetic, and  
electromagnetic energy released by a strike is humongous. We had to go to 3000W 
 
fast TVS diodes to achieve an acceptable level of protection from proximity  
strikes. I heard that a strike 100 meters away can still fry your antenna  
circuits.
 
>The most likely scenario is for
>induced voltages/current on  the braid due to nearby strikes. This should be
>grounded in a way that  does not allow the whole ground system that it is
>connected to to to be  "pulled up".


Yes, this is the case, but it's easy to induce a couple 100 Volts into  the 
center conductor through the exposed elements of the antenna. Also,  grounding 
can be an issue, since the earth has a fairly  high resistance as well. Have 
you seen the video where a strike hits a  soccer game, and all of the players 
fall over at the same time even though the  strike actually happened 10's of 
Meters away?
 
Average strikes have about 30,000 Amps and up to 200 Million Volts, with  
some super-bolts reaching 300,000 Amps. That's a lot of current going through 
an  
RG-8 cable. This kind of current can bring up the ground potential around 
your  house, let alone generate a lot of voltage on the antenna cable.
 
bye,
Said







**Ideas to please picky eaters. Watch video on AOL Living.  
(http://living.aol.com/video/how-to-please-your-picky-eater/rachel-campos-duffy/
2050827?NCID=aolcmp0030002598)
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[time-nuts] GPS Antenna Cable Splicing

[Matthew Smith]

Hi Folks

I'm not so hot on RF stuff (actually not so hot on anything above
50/60Hz - only studied power stuff) so thought I should ask:

I have a few GPS antennae here, all with 5m (15ft-ish) cables on them.
For me, that won't get the antenna anywhere near the highest ridgeline
of the house.  (Australian "Federation Style" house - lots of weird bits
of roof all over the place.)  So, I need to extend the cable.

1) Can I actually extend the cables, or is 5m as far as I can go - all
these are active antennae.

2) My normal way of extending a bit of coax would be to splice in an
appropriate length of similar cable.  To do this, I would strip the
outer insulation for a couple of inches on both pieces, pulling back the
braid.  I would then strip enough of the central insulation so that I
can solder the two cores together.  I insulate this with tape or
heatshrink, then solder the two braids together, wrap the whole thing
with aluminium foil and use a glued heatshrink to case the whole lot.

I know that this method works for 10-Base2 Ethernet and UHF Television,
 but have no idea if is suitable for SHF stuff like 1.5GHz...

3) How far apart do I need to space my GPS antennae, or can they be
nearly touching?  I suppose it would be easier if I used a distribution
amp (assuming such things exist at this frequency), but that sounds
expensive.

Cheers

M

-- 
Matthew Smith
Smiffytech - Technology Consulting & Web Application Development
Business: http://www.smiffytech.com/
Personal: http://www.smiffysplace.com/
LinkedIn: http://www.linkedin.com/in/smiffy

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[time-nuts] simple GPS nmea display.

[Luis Cupido]

Hi,

Long time ago I had a simple software (win 95/98)
that displayed GPS sats position ax/el and strength
etc from the nmea info.
I can't find it or remember its name and nowadays
searching google with anything containing GPS gets
tones of stuff... garbage in this perspective...

Can anyone point me to any simple program, must run
on older machines (windows 98) be and free.
I mean very basic stuff for sanity checks of system
antena etc.

Thanks.

Luis Cupido.
ct1dmk.


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Re: [time-nuts] GPS Antenna Cable Splicing

[Bruce Griffiths]

Matthew Smith wrote:
> Hi Folks
>
> I'm not so hot on RF stuff (actually not so hot on anything above
> 50/60Hz - only studied power stuff) so thought I should ask:
>
> I have a few GPS antennae here, all with 5m (15ft-ish) cables on them.
> For me, that won't get the antenna anywhere near the highest ridgeline
> of the house.  (Australian "Federation Style" house - lots of weird bits
> of roof all over the place.)  So, I need to extend the cable.
>
> 1) Can I actually extend the cables, or is 5m as far as I can go - all
> these are active antennae.
>
> 2) My normal way of extending a bit of coax would be to splice in an
> appropriate length of similar cable.  To do this, I would strip the
> outer insulation for a couple of inches on both pieces, pulling back the
> braid.  I would then strip enough of the central insulation so that I
> can solder the two cores together.  I insulate this with tape or
> heatshrink, then solder the two braids together, wrap the whole thing
> with aluminium foil and use a glued heatshrink to case the whole lot.
>
> I know that this method works for 10-Base2 Ethernet and UHF Television,
>  but have no idea if is suitable for SHF stuff like 1.5GHz...
>
> 3) How far apart do I need to space my GPS antennae, or can they be
> nearly touching?  I suppose it would be easier if I used a distribution
> amp (assuming such things exist at this frequency), but that sounds
> expensive.
>
> Cheers
>
> M
>
>   
Matthew

GPS distribution amplifiers are readily available, they appear from time 
to time on ebay.
Symmetricom 58537 4 port active smart splitters can be quite useful.
HP/Agilent/Symmetricom 58537A, 58536A are also useful.

The small diameter captive cable used by some GPS antennas tends to be 
somewhat lossy and it may be better to extend the length by using a 
lower loss cable.
Your splicing technique will create a significant discontinuity in the 
cable impedance at 1.57542 GHz.
The maximum cable length is determined by the maximum allowable cable 
attenuation between the antenna and the GPS receiver.
A high gain active antenna allows greater cable loss than a low gain 
active antenna or a passive antenna.

The better active antennas use a TNC, N or similar connector so you can 
use a custom length cable.

Bruce

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Re: [time-nuts] GPS Antenna Cable Splicing

[John Franke]

First; how long does the total length need to be?  With lower loss cables, 
10m is no problem.

Second; if you go to the trouble of adding a length of cable, it would be 
best if you replace as much of the 5m cable as possible with lower loss 
cable rather than just adding to the 5m cable.

John  WA4WDL

- Original Message - 
From: "Bruce Griffiths" <[EMAIL PROTECTED]>
To: "Discussion of precise time and frequency measurement" 

Sent: Saturday, March 01, 2008 8:25 AM
Subject: Re: [time-nuts] GPS Antenna Cable Splicing


> Matthew Smith wrote:
>> Hi Folks
>>
>> I'm not so hot on RF stuff (actually not so hot on anything above
>> 50/60Hz - only studied power stuff) so thought I should ask:
>>
>> I have a few GPS antennae here, all with 5m (15ft-ish) cables on them.
>> For me, that won't get the antenna anywhere near the highest ridgeline
>> of the house.  (Australian "Federation Style" house - lots of weird bits
>> of roof all over the place.)  So, I need to extend the cable.
>>
>> 1) Can I actually extend the cables, or is 5m as far as I can go - all
>> these are active antennae.
>>
>> 2) My normal way of extending a bit of coax would be to splice in an
>> appropriate length of similar cable.  To do this, I would strip the
>> outer insulation for a couple of inches on both pieces, pulling back the
>> braid.  I would then strip enough of the central insulation so that I
>> can solder the two cores together.  I insulate this with tape or
>> heatshrink, then solder the two braids together, wrap the whole thing
>> with aluminium foil and use a glued heatshrink to case the whole lot.
>>
>> I know that this method works for 10-Base2 Ethernet and UHF Television,
>>  but have no idea if is suitable for SHF stuff like 1.5GHz...
>>
>> 3) How far apart do I need to space my GPS antennae, or can they be
>> nearly touching?  I suppose it would be easier if I used a distribution
>> amp (assuming such things exist at this frequency), but that sounds
>> expensive.
>>
>> Cheers
>>
>> M
>>
>>
> Matthew
>
> GPS distribution amplifiers are readily available, they appear from time
> to time on ebay.
> Symmetricom 58537 4 port active smart splitters can be quite useful.
> HP/Agilent/Symmetricom 58537A, 58536A are also useful.
>
> The small diameter captive cable used by some GPS antennas tends to be
> somewhat lossy and it may be better to extend the length by using a
> lower loss cable.
> Your splicing technique will create a significant discontinuity in the
> cable impedance at 1.57542 GHz.
> The maximum cable length is determined by the maximum allowable cable
> attenuation between the antenna and the GPS receiver.
> A high gain active antenna allows greater cable loss than a low gain
> active antenna or a passive antenna.
>
> The better active antennas use a TNC, N or similar connector so you can
> use a custom length cable.
>
> Bruce
>
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Re: [time-nuts] simple GPS nmea display.

[n1jez]

Was it VisualGPS??

www.visualgps.net

73,
Mike, N1JEZ
"A closed mouth gathers no feet"

- Original Message - 
From: "Luis Cupido" <[EMAIL PROTECTED]>
To: "Discussion of precise time and frequency measurement" 

Sent: Saturday, March 01, 2008 8:21 AM
Subject: [time-nuts] simple GPS nmea display.


> Hi,
>
> Long time ago I had a simple software (win 95/98)
> that displayed GPS sats position ax/el and strength
> etc from the nmea info.
> I can't find it or remember its name and nowadays
> searching google with anything containing GPS gets
> tones of stuff... garbage in this perspective...
>
> Can anyone point me to any simple program, must run
> on older machines (windows 98) be and free.
> I mean very basic stuff for sanity checks of system
> antena etc.
>
> Thanks.
>
> Luis Cupido.
> ct1dmk.
>
>
> ___
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[time-nuts] Simple NMEA Display

[Tom Clifton]

From: Luis Cupido <[EMAIL PROTECTED]>
Can anyone point me to any simple program, must run
on older machines (windows 98) be and free.
I mean very basic stuff for sanity checks of system
antena etc.
--
Very basic, Very Simple and very Free.. Use the
hyperterminal program that comes with windows 4800
baud 8,N,1 and just look at the serial data

http://www.gpsinformation.org/dale/nmea.htm 

for information on how to decode by "hand"



  

Never miss a thing.  Make Yahoo your home page. 
http://www.yahoo.com/r/hs

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Re: [time-nuts] GPS-Attached Equipment Lightning Protection

[Robert Vassar]

Lightning simply doesn't behave like you might expect.  It's a DC  
current, but the rise times and current magnitude gives rise to AC  
behaviors.  The problem with "attractive protection" is they have to  
carry the full burden of the strike without fail.  If it fails, the  
current simply moves to the next easiest path.  This could be your  
equipment or even you.  Seemingly low impedance conductors like RG-8  
coax braid simply become copper patina at these energies.  Conductors  
need to have substantial mass, and straight conduction paths to  
ground.  Keep in mind that "ground" is a vague electrical proposition  
that the soil beneath your feet may or may not agree to.



Rob
KC6OOM/5


On Feb 29, 2008, at 7:33 PM, Alan Melia wrote:

> Hi All, all the comment has been about in-line protectors so far.  
> We in the
> UK do dot have the ferocity of lightning that is seen in some parts  
> of the
> USA but surely like all problems "prevention" is better. It is  
> probably not
> 100% but would it not be better to have a higher metal rod say 6  
> feet above
> the GPS antenna spearately grounded as with a building protection  
> system.
> The GPS antenna should then be placed in the "cone of protection"  
> of this
> rod. The likelyhood of getting any significant voltage on the centre
> conductor I would think would be very small. The most likely  
> scenario is for
> induced voltages/current on the braid due to nearby strikes. This  
> should be
> grounded in a way that does not allow the whole ground system that  
> it is
> connected to to to be "pulled up".
>
> As has been stated if you do get a direct hit on the GPS antenna  
> nothing
> will save your kit, but again (I believe I am right here) the vast  
> majority
> of the current from the strike will flow down the braid (if it doesnt
> vaporize it), So grounding the braid, preferably outside the  
> premises if a
> good idea. The size of the antenna is such that the build up of static
> should not be significantit is not a 200 foot long wire as I  
> use on MSF
> !
>
> If this is rubbish please say so but it sounds much more sensible  
> way of
> proceding to me.
>
> Cheers
> Alan G3NYK
>
>
>
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Re: [time-nuts] GPS-Attached Equipment Lightning Protection

[Jack Hudler]

I found a site that has some great links on grounding.

http://www.n0hr.com/hamradio/152/10/ham_radio0.htm the link to
"Choices and consequences of station lightning protection" 
http://members.cox.net/pc-usa/station/ground0.htm
is most excellent. I have implemented this (right down to common bonding the
grounding system for the pool equipment).

Jack
-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Matthew Smith
Sent: Thursday, February 28, 2008 3:40 PM
To: Time Nuts List
Subject: [time-nuts] GPS-Attached Equipment Lightning Protection

Hi Folks

Is anyone implementing any form of lightning protection for their
GPS-attached equipment?

If my antenna gets struck or we have a nearby hit (nearest strike to
ground since we moved here was about 470m away, IIRC), I would like to
limit the damage to the GPS module.

My thought was to stick an optoisolator or similar between the serial
and PPS pins and the level converter (MAX232 equivalent) and power the
GPS module itself with one of those little Meanwell high-isolation DC/DC
converters.  This is very similar to what I am planning to do with the
outside components of my 1-Wire weather system.

I'd be interested to know what everyone else is doing in this respect
(if anything).

Cheers

M


-- 
Matthew Smith
Smiffytech - Technology Consulting & Web Application Development
Business: http://www.smiffytech.com/
Personal: http://www.smiffysplace.com/
LinkedIn: http://www.linkedin.com/in/smiffy

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Re: [time-nuts] GPS-Attached Equipment Lightning Protection

[Didier Juges]

 

> -Original Message-
> From: [EMAIL PROTECTED] 
> [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED]
> Sent: Saturday, March 01, 2008 2:25 AM
> To: time-nuts@febo.com
> Subject: Re: [time-nuts] GPS-Attached Equipment Lightning Protection
> 
> 
> Yes, this is the case, but it's easy to induce a couple 100 
> Volts into  the center conductor through the exposed elements 
> of the antenna. 
>  
...
>  
> bye,
> Said
> 

This is due to a property known as "transfer impedance". Transfer impedance
is the ratio of voltage induced (diffferentially) on the center conductor of
a coax cable versus the current flowing through the braid (externally).

Transfer impedance is solely driven by shield/braid and termination
(connector) quality and has nothing to do with the characteristic impedance
of the cable. 

The effects of poor transfer impedance are similar to poor shielding and
usually related. Signals get in the cable from the outside. The remedies
against that are the same: better shield and better connectors.

It is seldom, if ever, specified when you buy a piece of cable. Cables with
solid outer conductor, such as semi-rigid cable, have much better (lower)
transfer impedance than woven braid cable for instance.

Didier KO4BB

No virus found in this outgoing message.
Checked by AVG Free Edition. 
Version: 7.5.516 / Virus Database: 269.21.2/1305 - Release Date: 2/29/2008
6:32 PM
 


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Re: [time-nuts] Simple NMEA Display

[Luis Cupido]

Hi Tom,

That I know ;-)
I meant something more visual :-)

Tks anyway.

Luis Cupido.
ct1dmk.



Tom Clifton wrote:
> From: Luis Cupido <[EMAIL PROTECTED]>
> Can anyone point me to any simple program, must run
> on older machines (windows 98) be and free.
> I mean very basic stuff for sanity checks of system
> antena etc.
> --
> Very basic, Very Simple and very Free.. Use the
> hyperterminal program that comes with windows 4800
> baud 8,N,1 and just look at the serial data
> 
> http://www.gpsinformation.org/dale/nmea.htm 
> 
> for information on how to decode by "hand"
> 
> 
> 
>   
> 
> Never miss a thing.  Make Yahoo your home page. 
> http://www.yahoo.com/r/hs
> 
> ___
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Re: [time-nuts] simple GPS nmea display.

[Luis Cupido]

Tks, Mike,

It was something very similar
Will try that one tks.

Luis Cupido.
ct1dmk.

[EMAIL PROTECTED] wrote:
> Was it VisualGPS??
> 
> www.visualgps.net
> 
> 73,
> Mike, N1JEZ
> "A closed mouth gathers no feet"
> 
> - Original Message - 
> From: "Luis Cupido" <[EMAIL PROTECTED]>
> To: "Discussion of precise time and frequency measurement" 
> 
> Sent: Saturday, March 01, 2008 8:21 AM
> Subject: [time-nuts] simple GPS nmea display.
> 
> 
>> Hi,
>>
>> Long time ago I had a simple software (win 95/98)
>> that displayed GPS sats position ax/el and strength
>> etc from the nmea info.
>> I can't find it or remember its name and nowadays
>> searching google with anything containing GPS gets
>> tones of stuff... garbage in this perspective...
>>
>> Can anyone point me to any simple program, must run
>> on older machines (windows 98) be and free.
>> I mean very basic stuff for sanity checks of system
>> antena etc.
>>
>> Thanks.
>>
>> Luis Cupido.
>> ct1dmk.
>>
>>
>> ___
>> time-nuts mailing list -- time-nuts@febo.com
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>> and follow the instructions there.
>>
> 
> 
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Re: [time-nuts] simple GPS nmea display.

[Luis Cupido]

Tested, It works great.
tks.

lc
ct1dmk.


[EMAIL PROTECTED] wrote:
> Was it VisualGPS??
> 
> www.visualgps.net
> 
> 73,
> Mike, N1JEZ
> "A closed mouth gathers no feet"
> 
> - Original Message - 
> From: "Luis Cupido" <[EMAIL PROTECTED]>
> To: "Discussion of precise time and frequency measurement" 
> 
> Sent: Saturday, March 01, 2008 8:21 AM
> Subject: [time-nuts] simple GPS nmea display.
> 
> 
>> Hi,
>>
>> Long time ago I had a simple software (win 95/98)
>> that displayed GPS sats position ax/el and strength
>> etc from the nmea info.
>> I can't find it or remember its name and nowadays
>> searching google with anything containing GPS gets
>> tones of stuff... garbage in this perspective...
>>
>> Can anyone point me to any simple program, must run
>> on older machines (windows 98) be and free.
>> I mean very basic stuff for sanity checks of system
>> antena etc.
>>
>> Thanks.
>>
>> Luis Cupido.
>> ct1dmk.
>>
>>
>> ___
>> time-nuts mailing list -- time-nuts@febo.com
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>> and follow the instructions there.
>>
> 
> 
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[time-nuts] Timing Measurements

[GandalfG8]

Hi All
 
This might be old news but I just came across this link  to a Symmetricom 
presentation on timing measurements and thought  it interesting
 
_www.iee.org/OnComms/PN/communications/www.iee.org/OnComms/PN/com_ 
(http://www.iee.org/OnComms/PN/communications/005%20-%20Lee%20Cosart.pdf)  
 
regards
 
Nigel
GM8PZR



   
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Re: [time-nuts] Simple NMEA Display

[randy warner]

Luis,

The one I have been using for years is Visual GPS. This program has a very
nice graphical interface, and if you look at some of the other programs out
there supplied by vendors for their GPS boards, you will see that they are
almost always derived from Visual GPS. Those of you out there that use
Motorola's WinOncore12 will notice the EXTREME similarity between VisualGPS
and WinOncore12. You can download Visual GPS from Monte Variakojis's site
at: www.visualgps.net. Monte also offers several other utilities for little
or no cost.

Randy

_

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Luis Cupido
Sent: Saturday, March 01, 2008 8:01 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Simple NMEA Display

Hi Tom,

That I know ;-)
I meant something more visual :-)

Tks anyway.

Luis Cupido.
ct1dmk.



Tom Clifton wrote:
> From: Luis Cupido <[EMAIL PROTECTED]>
> Can anyone point me to any simple program, must run
> on older machines (windows 98) be and free.
> I mean very basic stuff for sanity checks of system
> antena etc.
> --
> Very basic, Very Simple and very Free.. Use the
> hyperterminal program that comes with windows 4800
> baud 8,N,1 and just look at the serial data
> 
> http://www.gpsinformation.org/dale/nmea.htm 
> 
> for information on how to decode by "hand"
> 
> 
> 
>


> Never miss a thing.  Make Yahoo your home page. 
> http://www.yahoo.com/r/hs
> 
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> To unsubscribe, go to
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Re: [time-nuts] GPS Antenna Cable Splicing

[Morris Odell]

> Date: Sat, 01 Mar 2008 19:52:03 +1030
> From: Matthew Smith <[EMAIL PROTECTED]>
> Subject: [time-nuts] GPS Antenna Cable Splicing
> To: Time Nuts List 
> Message-ID: <[EMAIL PROTECTED]>
> Content-Type: text/plain; charset=UTF-8
>
> 1) Can I actually extend the cables, or is 5m as far as I can go - all
> these are active antennae.
>
> 2) My normal way of extending a bit of coax would be to splice in an
> appropriate length of similar cable.  To do this, I would strip the
> outer insulation for a couple of inches on both pieces, pulling back the
> braid.  I would then strip enough of the central insulation so that I
> can solder the two cores together.  I insulate this with tape or
> heatshrink, then solder the two braids together, wrap the whole thing
> with aluminium foil and use a glued heatshrink to case the whole lot.

Although the discussion here often revolves around the "edge of the 
envelope", there are some things that might not need that level of detail. I 
have a similar problem, with a workshop in the basement and a GPS antenna on 
a balcony 3 stories up. I had a 15 metre length of RG213 running between 
those two places for a HF antenna which is no longer used. It already had 
UHF (PL-259) connectors on the end. I just made up a little adaptor for the 
GPS antenna lead using a cheap plastic box, a SO-239 socket and plenty of 
silicone sealant.

It works perfectly although I know a TDR would have apoplexy looking into 
it. I use it for non-critical stuff and testing, my Z3815A had a dedicated 
antenna with a proper lead.

Morris



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Re: [time-nuts] GPS Antenna Cable Splicing

[Matthew Smith]

Quoth Bruce Griffiths at 2008-03-01 23:55...
> GPS distribution amplifiers are readily available, they appear from time 
> to time on ebay.
> Symmetricom 58537 4 port active smart splitters can be quite useful.
> HP/Agilent/Symmetricom 58537A, 58536A are also useful.
Think I'll investigate these - have two antennas on the roof, one in
use, the other a redundant spare that I can switch over by swapping a
plug up in the loft.

> The small diameter captive cable used by some GPS antennas tends to be 
> somewhat lossy and it may be better to extend the length by using a 
> lower loss cable.
Which is what I've got.  I have a part-reel of satellite TV cable, so
will make up an extension with that and see how it behaves.

> Your splicing technique will create a significant discontinuity in the 
> cable impedance at 1.57542 GHz.
The joint will now be made indoors so plugs will be used.

Quoth John Franke at 2008-03-02 00:11...
> First; how long does the total length need to be?  With lower loss cables, 
> 10m is no problem.
It will probably be 10m if I take the indoor (but more difficult) route.

Thanks for your input, folks!

Cheers

M

-- 
Matthew Smith
Smiffytech - Technology Consulting & Web Application Development
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[time-nuts] Trimble 36576-A GPS Module

[Matthew Smith]

Hi

Does anyone have one of these or is able to identify it?

This module looks very much like an ACE unit and indeed the eBay
vendor's link to documentation is to an ACE II.

However, the ACE units have a 90 degree SMA antenna connector whereas
this unit has a vertical, unthreaded connector od=4.97mm.

Typically, searching for this number on the Trimble site comes up with
nothing, nor the PII-M1 or 9923A printed on the PCB.

The second mystery is that the supplied antenna, a 40767-40 has another
connector that I cannot identify.  The specification for this antenna
says that it has an SMA connector.  Once again, what is on the end of
the cable is something else.

There is a fly-lead to connect the board to the antenna - different
connectors on both ends, none threaded.

What I really want to know, more than anything, is what these connectors
are so that I can get adapters for my cable extension.

Or should I just chop the ends off the antenna cable and fly lead and
chuck on something a bit more standard like a BNC connector?

Cheers

M

-- 
Matthew Smith
Smiffytech - Technology Consulting & Web Application Development
Business: http://www.smiffytech.com/
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Re: [time-nuts] Trimble 36576-A GPS Module

[Bruce Griffiths]

Matthew Smith wrote:
> Hi
>
> Does anyone have one of these or is able to identify it?
>
> This module looks very much like an ACE unit and indeed the eBay
> vendor's link to documentation is to an ACE II.
>
> However, the ACE units have a 90 degree SMA antenna connector whereas
> this unit has a vertical, unthreaded connector od=4.97mm.
>
> Typically, searching for this number on the Trimble site comes up with
> nothing, nor the PII-M1 or 9923A printed on the PCB.
>
> The second mystery is that the supplied antenna, a 40767-40 has another
> connector that I cannot identify.  The specification for this antenna
> says that it has an SMA connector.  Once again, what is on the end of
> the cable is something else.
>
> There is a fly-lead to connect the board to the antenna - different
> connectors on both ends, none threaded.
>
> What I really want to know, more than anything, is what these connectors
> are so that I can get adapters for my cable extension.
>
> Or should I just chop the ends off the antenna cable and fly lead and
> chuck on something a bit more standard like a BNC connector?
>
> Cheers
>
> M
>
>   
Mathew

Some pictures of the connectors in question would be useful.

Bruce

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Re: [time-nuts] Trimble 36576-A GPS Module

[Matthew Smith]

Quoth Bruce Griffiths at 2008-03-02 11:05...

> Mathew
> 
> Some pictures of the connectors in question would be useful.
> 
> Bruce

Good thinking!

The grid on my notebook is 5mm x 5mm, for those shots where the ruler is
out of the picture.

Overview - module with flylead



Detail of connector that mates with antenna cable.  The thread that is
visible is for panel mounting.



Detail of board-end of flylead and connector on board.



Couldn't get any closer with that lens...


Cheers

M

-- 
Matthew Smith
Smiffytech - Technology Consulting & Web Application Development
Business: http://www.smiffytech.com/
Personal: http://www.smiffysplace.com/
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Re: [time-nuts] Trimble 36576-A GPS Module

[Chris Kuethe]

On Sat, Mar 1, 2008 at 5:05 PM, Matthew Smith <[EMAIL PROTECTED]> wrote:
>  Good thinking!
>
>  The grid on my notebook is 5mm x 5mm, for those shots where the ruler is
>  out of the picture.

Looks like MCX.

I have connectors matching that description and general look on my
Oncore UT+, and I used a Garmin MCX-terminated antenna.

CK

-- 
GDB has a 'break' feature; why doesn't it have 'fix' too?

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Re: [time-nuts] Trimble 36576-A GPS Module

[Bruce Griffiths]

Matthew Smith wrote:
> Quoth Bruce Griffiths at 2008-03-02 11:05...
>
>   
>> Mathew
>>
>> Some pictures of the connectors in question would be useful.
>>
>> Bruce
>> 
>
> Good thinking!
>
> The grid on my notebook is 5mm x 5mm, for those shots where the ruler is
> out of the picture.
>
> Overview - module with flylead
>
> 
>
> Detail of connector that mates with antenna cable.  The thread that is
> visible is for panel mounting.
>
> 
>
> Detail of board-end of flylead and connector on board.
>
> 
>
> Couldn't get any closer with that lens...
>
>
> Cheers
>
> M
>
>   
Mathew

The PCB connector is probably an MCX connector.

The other end looks more like an SMB connector.

Another popular GPS connector is the MMCX.

Bruce

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Re: [time-nuts] Trimble 36576-A GPS Module

[Matthew Smith]

Quoth Matthew Smith at 2008-03-02 11:35...
> Overview - module with flylead
> 
> 

I should mention that the two ends of the flylead both have a pin in the
centre of the connector and are of differing sizes.  The socket on the
antenna lead (not shown) has cuts around the edge for the flylead
connector to snap in, the socket on the board is solid.  The snap cuts
are on the plug.

-- 
Matthew Smith
Smiffytech - Technology Consulting & Web Application Development
Business: http://www.smiffytech.com/
Personal: http://www.smiffysplace.com/
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Re: [time-nuts] Trimble 36576-A GPS Module

[Chris Kuethe]

On Sat, Mar 1, 2008 at 5:16 PM, Matthew Smith <[EMAIL PROTECTED]> wrote:
>  The socket on the
>  antenna lead (not shown) has cuts around the edge for the flylead
>  connector to snap in, the socket on the board is solid.  The snap cuts
>  are on the plug.

SMB, sometimes known as OCX

-- 
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Re: [time-nuts] Trimble 36576-A GPS Module

[Matthew Smith]

Quoth Chris Kuethe at 2008-03-02 11:40...
> Looks like MCX.
> 
> I have connectors matching that description and general look on my
> Oncore UT+, and I used a Garmin MCX-terminated antenna.

That's that one confirmed, thanks.  Just fished out the antenna for my
Oncore modules and yes, it fits into the socket on the PCB.

Cheers

M


-- 
Matthew Smith
Smiffytech - Technology Consulting & Web Application Development
Business: http://www.smiffytech.com/
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Re: [time-nuts] Trimble 36576-A GPS Module

[Matthew Smith]

Quoth Chris Kuethe at 2008-03-02 11:49...
> SMB, sometimes known as OCX

Excellent!

Thanks guys.

Cheers

M



-- 
Matthew Smith
Smiffytech - Technology Consulting & Web Application Development
Business: http://www.smiffytech.com/
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Re: [time-nuts] Trimble 36576-A GPS Module

[Chris Kuethe]

On Sat, Mar 1, 2008 at 5:22 PM, Matthew Smith <[EMAIL PROTECTED]> wrote:
>  Excellent!
>
>  Thanks guys.

Fans of Neal Stephenson (in particular Snow Crash) may consider this
as an example of "condensing fact from the vapor of nuance".

-- 
GDB has a 'break' feature; why doesn't it have 'fix' too?

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