Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 15-07-2022, 13:02   #1
Registered User
 
BigAl.NZ's Avatar

Join Date: Sep 2008
Location: Auckland, NZ
Boat: Hood 38 - Wauquiez
Posts: 738
Replace Male SMA on GPS antenna

Has anyone tried to replace a male SMA connector on a GPS antenna wire?

I suspect the center conductor has broken, and I am crossing fingers that its broken near the existing connector. I have a bit of surplus length so I can re terminate.

The wire itself is not the usual 8mm or so thick coax, this GPS antenna wire is more like 3mm wide (very thin) and black in color. Never tried one that thin.

Is there a way to test the cable and see how far down the wire the break is?
BigAl.NZ is offline   Reply With Quote
Old 15-07-2022, 14:46   #2
Registered User
 
Hartleyg's Avatar

Join Date: Mar 2014
Location: Atlantic Ocean
Boat: Tayana 48DS 48'
Posts: 380
Images: 8
Re: Replace Male SMA on GPS antenna

3mm sounds like RG-174 cable - you can buy connectors for this cable online though most connectors for this size cable require a properly-sized crimp tool. I would think NZ would have a supply house for this sort of thing.

There is an instrument that can tell where a break is - its called a time-domain reflectometer (TDR), and while lab-grade versions are extremely expensive, if you know someone who has an instrument called a "NanoVNA", this can be configured to work as a TDR. For you, it would be cheaper to replace the cable and connector rather than acquire one, but they are useful for many other antenna and feedline checks, so "radio guys" tend to have them around.

Hope this helps!

Hartley
S/V Atsa
Hartleyg is offline   Reply With Quote
Old 15-07-2022, 14:54   #3
Registered User
 
BigAl.NZ's Avatar

Join Date: Sep 2008
Location: Auckland, NZ
Boat: Hood 38 - Wauquiez
Posts: 738
Re: Replace Male SMA on GPS antenna

Awsome answer - thanks.

The cable (now that I am on the boat) is ECE R118. Long story but since the other end is sealed and hardwired I am really looking to replace the connector.
BigAl.NZ is offline   Reply With Quote
Old 15-07-2022, 15:21   #4
Moderator and Certifiable Refitter
 
Wotname's Avatar

Join Date: Jan 2008
Location: South of 43 S, Australia
Boat: C.L.O.D.
Posts: 21,277
Re: Replace Male SMA on GPS antenna

Breaks usually occur just where the coax exits the connector. In absence of any external visual damage elsewhere, cut a few inches off the end of the coax (assuming you have enough to work with) and fit a new SMA connector. SMA connectors are available in crimp and solder/clamp styles. For a one off, the solder/clamp is probably more convenient unless you have access to the correct crimping tool.

You will need good eyesight.
__________________
All men dream: but not equally. Those who dream by night in the dusty recesses of their minds wake in the day to find it was vanity: but the dreamers of the day are dangereous men, for they may act their dreams with open eyes, to make it possible. T.E. Lawrence
Wotname is online now   Reply With Quote
Old 15-07-2022, 15:26   #5
Registered User
 
BigAl.NZ's Avatar

Join Date: Sep 2008
Location: Auckland, NZ
Boat: Hood 38 - Wauquiez
Posts: 738
Re: Replace Male SMA on GPS antenna

Quote:
Originally Posted by Wotname View Post
Breaks usually occur just where the coax exits the connector. In absence of any external visual damage elsewhere, cut a few inches off the end of the coax (assuming you have enough to work with) and fit a new SMA connector. SMA connectors are available in crimp and solder/clamp styles. For a one off, the solder/clamp is probably more convenient unless you have access to the correct crimping tool.

You will need good eyesight.
Agreed - and thats where I hope the break is - yes I have surplus cable. I am now trying to identify the correct SMA for the cable size. (2.8mm dia OD)
BigAl.NZ is offline   Reply With Quote
Old 15-07-2022, 15:47   #6
Registered User
 
Hartleyg's Avatar

Join Date: Mar 2014
Location: Atlantic Ocean
Boat: Tayana 48DS 48'
Posts: 380
Images: 8
Re: Replace Male SMA on GPS antenna

ECE R118 is not a cable size, unfortunately - its a European fire-retardance spec.

But RG-174 has an OD of 2.79mm, so I'm sure thats what you have!

Hartley
S/V Atsa
Hartleyg is offline   Reply With Quote
Old 15-07-2022, 16:46   #7
Moderator and Certifiable Refitter
 
Wotname's Avatar

Join Date: Jan 2008
Location: South of 43 S, Australia
Boat: C.L.O.D.
Posts: 21,277
Re: Replace Male SMA on GPS antenna

Yes, almost 100% sure it will be RG-174.
An SMA suitable for RG-174 will be OK even if the cable is slightly different to RG-174.
__________________
All men dream: but not equally. Those who dream by night in the dusty recesses of their minds wake in the day to find it was vanity: but the dreamers of the day are dangereous men, for they may act their dreams with open eyes, to make it possible. T.E. Lawrence
Wotname is online now   Reply With Quote
Old 15-07-2022, 18:00   #8
Registered User
 
BigAl.NZ's Avatar

Join Date: Sep 2008
Location: Auckland, NZ
Boat: Hood 38 - Wauquiez
Posts: 738
Re: Replace Male SMA on GPS antenna

Thanks guys.
BigAl.NZ is offline   Reply With Quote
Old 17-07-2022, 23:01   #9
Registered User
 
BigAl.NZ's Avatar

Join Date: Sep 2008
Location: Auckland, NZ
Boat: Hood 38 - Wauquiez
Posts: 738
Re: Replace Male SMA on GPS antenna

Quote:
Originally Posted by Wotname View Post
Breaks usually occur just where the coax exits the connector. In absence of any external visual damage elsewhere, cut a few inches off the end of the coax (assuming you have enough to work with) and fit a new SMA connector. SMA connectors are available in crimp and solder/clamp styles. For a one off, the solder/clamp is probably more convenient unless you have access to the correct crimping tool.

You will need good eyesight.
Replaced SMA - and we are back in business. Thanks guys.
BigAl.NZ is offline   Reply With Quote
Old 17-07-2022, 23:48   #10
Moderator and Certifiable Refitter
 
Wotname's Avatar

Join Date: Jan 2008
Location: South of 43 S, Australia
Boat: C.L.O.D.
Posts: 21,277
Re: Replace Male SMA on GPS antenna

Thanks for the update, it is always good to hear how these things work out in the end!

Well done for solving it -
__________________
All men dream: but not equally. Those who dream by night in the dusty recesses of their minds wake in the day to find it was vanity: but the dreamers of the day are dangereous men, for they may act their dreams with open eyes, to make it possible. T.E. Lawrence
Wotname is online now   Reply With Quote
Old 30-07-2022, 02:01   #11
Registered User
 
BigAl.NZ's Avatar

Join Date: Sep 2008
Location: Auckland, NZ
Boat: Hood 38 - Wauquiez
Posts: 738
Re: Replace Male SMA on GPS antenna

Spoke to soon - the GPS crapped out again today. I have nothing to loose now by chopping the GPS antenna cable near where it comes out of the puck, attaching a female connector and then replacing the rest of the cable run.

Has anybody done this before and had it work? I am tempted to replace RG174 with RG58 - but thoughts?
BigAl.NZ is offline   Reply With Quote
Old 30-07-2022, 02:33   #12
Moderator and Certifiable Refitter
 
Wotname's Avatar

Join Date: Jan 2008
Location: South of 43 S, Australia
Boat: C.L.O.D.
Posts: 21,277
Re: Replace Male SMA on GPS antenna

You haven't told us how long the coax run is but if it is greater than say 6', then RG174 is a poor choice. 1 or 2 feet is OK.

RG174 has about 2.5 to 3 times the loss of RG58.
Attached Thumbnails
Click image for larger version

Name:	Screen Shot 2022-07-30 at 7.29.17 pm.png
Views:	40
Size:	250.5 KB
ID:	261878  
__________________
All men dream: but not equally. Those who dream by night in the dusty recesses of their minds wake in the day to find it was vanity: but the dreamers of the day are dangereous men, for they may act their dreams with open eyes, to make it possible. T.E. Lawrence
Wotname is online now   Reply With Quote
Old 30-07-2022, 02:52   #13
Registered User
 
BigAl.NZ's Avatar

Join Date: Sep 2008
Location: Auckland, NZ
Boat: Hood 38 - Wauquiez
Posts: 738
Re: Replace Male SMA on GPS antenna

Quote:
Originally Posted by Wotname View Post
You haven't told us how long the coax run is but if it is greater than say 6', then RG174 is a poor choice. 1 or 2 feet is OK.

RG174 has about 2.5 to 3 times the loss of RG58.
The antenna puck came with 5m (yes meters!!!) of RG174. I am tempted to replace with RG58 for the reason you gave - I was surprised they used RG174.....I actually don't need a 5m run either. I can probably get away with 4m - its been trimmed to that length anyway as a result of me replacing the SMA connectors.

Will the additional connection just after the puck not result in too much loss?
BigAl.NZ is offline   Reply With Quote
Old 30-07-2022, 04:20   #14
Moderator and Certifiable Refitter
 
Wotname's Avatar

Join Date: Jan 2008
Location: South of 43 S, Australia
Boat: C.L.O.D.
Posts: 21,277
Re: Replace Male SMA on GPS antenna

The lower loss of the RG58 will more than make up for the connector loss.
__________________
All men dream: but not equally. Those who dream by night in the dusty recesses of their minds wake in the day to find it was vanity: but the dreamers of the day are dangereous men, for they may act their dreams with open eyes, to make it possible. T.E. Lawrence
Wotname is online now   Reply With Quote
Old 30-07-2022, 13:09   #15
Registered User
 
BigAl.NZ's Avatar

Join Date: Sep 2008
Location: Auckland, NZ
Boat: Hood 38 - Wauquiez
Posts: 738
Re: Replace Male SMA on GPS antenna

Quote:
Originally Posted by Wotname View Post
The lower loss of the RG58 will more than make up for the connector loss.
Good to know. Thanks for your input. Hoping that this fault, which is very intermittent is somewhere in the cable and not the antenna. After my last repair I certainly "detect" lots of satellites, just perhaps the signal is not strong enough for a fix. I also wondered about whether the cable being routed through the stainless steel radar arch poles next to the solar wiring was the issue, but even when outside the radar arch the issue persisted.

The join maybe exposed to the elements, so I was just going to coat it in a generous blob of sika flex unless there is a more elegant way.
BigAl.NZ is offline   Reply With Quote
Reply

Tags
antenna, gps

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
need to replace gps antenna to old west marine ais-1000 familysailing Marine Electronics 1 11-07-2020 13:11
Lines - To replace, or not to replace? TooCoys General Sailing Forum 31 25-04-2017 13:32
HF antenna Back Stay vs. Screwdriver antenna BocaIII Marine Electronics 34 13-04-2014 02:15
Old Shakespeake Antenna vs. New Shakespeare Antenna zboss Marine Electronics 2 21-08-2013 08:27
Replace Compass at Helm with GPS hoppy Marine Electronics 52 08-10-2011 07:33

Advertise Here


All times are GMT -7. The time now is 05:17.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.