Iridium Go Coax Cable - Howto joint

[Segelplaner]

Hi,
I need to join two Iridium Go external antenna cables, and have obviously no idea what I am doing.

I bought an prepared antennakit, but needed to cut off one of the TNC-contacts to be able to install the cable through boat. (I wonder who keeps the contacts?) The cable was also some 3m too short.

Now I need to find solution:

• What type of Coax cable for Iridium go?
• What type of Connectors between cable?
• Can you solder two Coax cables together and skip connectors?
• Tips and tricks to make a good Coax installation?

In the attached picture i tried to attache a "soft" coax cable with the supplied "hard" coax cable. I can probably try different scenarios into infinity without success.

Thanks for all advice!
Jonas

[sailormed]

Coax cables are designed for a frequency range. Make sure you use matching cables. Use standard connectors on both cables for the joint. Do not try to solder. Good luck.Also look at the loss per mesure of length if you are getting a weak signal.

[Palarran]

I've been using my Iridium Go consistently for the last 3 months without an external antenna and had zero problems with signal strength. Have you tried it?

[donradcliffe]

I have used the GO, and would recommend the external antenna. As far as I can tell, it uses a 50 ohm cable with TNC connectors. There are readily available Reverse Polarity TNC extension cables, used for routers. I'm not sure whether they would work for the GO, but I would try one.

To reattach a TNC connector, see

https://www.youtube.com/watch?v=XfA0JVRJSxU

[CarstenWL]

Hej Jonas,

how long is the needed length of cable between the Go! and antenna? Did you buy the original 'coax cable for the kit'? Think they are using LMR-400 but maybe I do not remember well ... Have a look on the cable ...

You will either need to extend with connectors or even better pull in a new complete run (I can suggest a cable type than) and install new TNC connectors.

Eventually I might be in Stockholm in two weeks or so and could give you a hand but its not confirmed yet.

Kind regards from Laboe / Kiel

Carsten

[Segelplaner]

Great advices in short notice, this is truly an amazing forum!
One of my options is to make an new complete run, expensive lesson learned - again

During my testing I observed that the Iridium-signal in the boat was not that weak, compared to the signal with the external antenna connected.

Thanks for the video!

Jonas

[Emerald Sea]

The coax Iridium supply/recommend is the LMR400. They also recommend no longer than 10m after which you’ll lose signal strength. Use a mechanical type of connector you can find in an hobby electrical/electronics shop. Be sure to seal it with a heat shrink sleeve afterwards.
There are a number of good YouTube vids for making up coax connections.

[CarstenWL]

... Airborne 10 CE (Home) would be a very good 'replacement' in Europe for LMR-400.

About the same if not a bit less loss on 1600Mhz.

You do not want 'to splice' Coax intended to use for TX/RX at these frequencies.

Regards,

Carsten

[Auspicious]

Originally Posted by Segelplaner

One of my options is to make an new complete run, expensive lesson learned - again

Cheaper than having someone else do it, and cheaper yet from having someone else do it poorly.

Originally Posted by CarstenWL

You do not want 'to splice' Coax intended to use for TX/RX at these frequencies.

Definitely correct. The only thing worse--much worse--than a coax connection is a splice.

Originally Posted by Emerald Sea

The coax Iridium supply/recommend is the LMR400. They also recommend no longer than 10m after which you’ll lose signal strength.

You lose signal strength with every inch. Someone had to decide how long was "too long" and some engineer at Iridium decided on 10m. He didn't guess. He (or she) looked at the relative performance of the external antenna to the in-built one and the loss of LMR-400 and made a call. Shorter is better. 11m won't make it non-functional.